RoadTest: Apply to review the ams OSRAM AS1170 Evaluation Kit
Author: chloro
Creation date:
Evaluation Type: Evaluation Boards
Did you receive all parts the manufacturer stated would be included in the package?: True
What other parts do you consider comparable to this product?: The TI LM36011/LM3644 and some analog devices’ IR flash drivers seem to be closest competitors, although after trying out the AS1170 EVK kit, it seems that AS1170 would be better suited for experimenting with infrared from an embedded design point of view.
What were the biggest problems encountered?: The primary problem was dealing with GUI to chip interfacing. It solved later.
Detailed Review:
I must say that when I saw that the AS1170 had been scheduled on the Element14 RoadTest program schedule, I was immediately interested in it, and I was keen on getting my hands on it and reviewing it.
I would first of all like to thank OwainM for making all of this possible from start to finish. I would also like to thank E14Alice for shipping the package.
The AS1170 is a high-current driver for LEDs and VCSELs. The device is based upon an inductive and highly efficient DC-DC step-up converter. The chip has two independent current sinks and can supply up to 2 A in total. The device operates at a fixed frequency of 4 MHz and is primarily intended for the following applications: smartphone camera flash lighting, 3D structured light sensing, and active stereo vision. The chip communicates via I2C and has the ability to perform PWM dimming. The chip also has a flash mode with strobe control. The device has a comprehensive range of protection features and is contained in a very small WL-CSP package measuring just 2.25 mm x 1.5 mm x 0.6 mm.
The thing that caught my attention was the device’s ability to have two independent current sinks and the ability to output up to 2 A in total. I am working with IR illumination and was looking for this sort of device.
When I got the package, I'll admit that I was expecting nothing out of the ordinary. Which, again, is perfectly all right for an engineering tool. When I opened the box, I saw that there were four circuit boards neatly stacked on top of each other, as well as a micro-USB cable. First of all, I was surprised by how compact all of the items were. The main EVK board itself is smaller than than a credit card, and the IR LED breakout board that connects to it is even smaller.
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AS1170 Evaluation Kit Packaging |
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AS1170 EVK – Box Contents Overview |
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AS1170 Evaluation Board |
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ESP32-S2 DevKit M1 Board |
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ESP32-S2 DevKit M1 Board |
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Support & Resources Card |
What I really liked was that first moment of seeing everything together. The kit is nicely packed in a box lined with foam, which already gave me that sense of premium and professionalism. It felt like they took the evaluation experience seriously, and right there, I felt confident that the documentation and support would be of similar quality.
After the initial unboxing, I started examining each of the components in detail to understand their purpose, design, and how each of them contributes to real-world IR illumination and sensing applications. I recall sitting at my workbench and going through each of the boards one by one, and I have to say, I became more and more impressed as I looked more closely.
The heart of the kit is the AS1170 Evaluation Board (also marked as “AS1170 High Current LED/VCSEL Driver”). It is a compact, black PCB measuring approximately 60 mm × 45 mm, with clear silkscreen labeling.
Key features visible on the board:
P1616 footprint) – these are the default onboard emittersOne thing that surprised me was that the board was very thoughtfully laid out. The board is designed for both GUI tests and embedded development. The connectors are also clearly labeled, making it very easy for new users. While I am an experienced user of many evaluation boards, I found it refreshing that I did not have to search through the schematics to figure out where to plug in my USB cable.
The board includes several important jumpers and connectors that control its behaviour. I genuinely spent a good few minutes just reading through the jumper table before touching anything — and I am glad I did, because getting this wrong, especially around the power path, could have caused real problems.
Input Description BU1 VBAT Power Input Terminal: This is a red screw terminal used to connect the positive line from an external bench power supply. Only use this when the LED current is above 450 mA and USB power can’t provide enough power. The AS1170’s VIN range is "2.7 V to 4.4 V." BU2 GND Terminal: This is the black screw terminal you use to connect the ground from an external power supply. S1 Strobe Button: This is a physical button that’s wired to the AS1170’s STROBE pin. When the device is set to strobe-controlled flash mode, pressing it will trigger a flash. This really helped when I first started testing, since I could send IR pulses without having to write any code. J1 External LED Board Connector: This is the connector where you plug in the IR LED breakout board. If you’re using J1, take off J5 so the onboard LEDs are disconnected. J2 MCU board connector (lower header) It brings out SCL, SDA, STROBE, and 3.3V signals going between the ESP32-S2 and the AS1170 circuit. This is the I2C communication route. J3 MCU Board Connector (upper header): This is an extra header connector for the ESP32-S2 module. J5 Onboard LED Enable: If you install this jumper, it connects the onboard SFH41747 LEDs. Take it off when you’re using the external breakout board. J6 VBAT to 3V3 Jumper: If you install it, J6 lets the ESP32-S2 use its 3.3V rail to supply the AS1170’s VIN. This is the default setup for running low-current tests over USB. The key point is that if you hook up a lab bench power supply to BU1/BU2 for high-current use, you need to remove J6 so the bench supply voltage doesn’t get sent back into the MCU board. J7 VBAT/GND Measurement Pin: This is a handy two-pin header that lets you check the supply voltage using a multimeter or an oscilloscope. Honestly, I thought the J6 detail was the one most likely to catch a new user off guard. The idea that leaving J6 in place while connecting a bench supply could back-feed voltage into the ESP32-S2 is the kind of subtle thing that is easy to miss on a first read. I was glad I caught it before making that mistake.
For a deeper understanding of the board design, jumper configuration, and PCB layout, the following diagrams from the official documentation are provided.
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Figure 1.1: Jumper and connector overview showing all key interfaces and their functions on the AS1170 EVK. |
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Figure 1.2: PCB layout view highlighting routing layers and internal connections of the AS1170 evaluation boardThese diagrams show the top layer (red), inner layers for GND and VBAT, and bottom layer. They are very helpful for understanding power distribution, signal routing, and thermal design of the boost converter. When I first looked at the layout, what caught my eye was that it is packed tightly around the AS1170 in a manner that is specifically recommended in the datasheet layout recommendations for minimizing the area of the high-frequency switching current loops. |
The complete circuit diagram showing power input, boost converter, LED outputs, I²C interface, and ESP32-S2 connection points.
If we go through the provided documentation, it shows that the internal circuit diagram reveals a complete power management subsystem integrated into the single WL-CSP die.
The key functional blocks are worth tracing through:
The DCDC Analog block sits at the centre, controlling the PMOS and NMOS switches (SW1/2) at a fixed 4 MHz clock. The oscillator on the bottom left feeds the clock throughout the chip. A ramp generator and comparator implement peak current-mode control of the boost converter.
The current sinks on LED_OUT1 and LED_OUT2 are controlled by the digital core, which translates the I2C register values into a reference current for the current DAC. This is how the LED current is precisely set — not by varying voltage, but by directly controlling the current sinking through the LED.
The VDS comparators continuously monitor the voltage across the current sinks. There are two thresholds: VLOW_VDS (~320 mV) and VHIGH_VDS (~900 mV). These are used to determine whether the boost converter needs to operate at higher or lower duty cycle, and they feed into the 4 MHz / 1 MHz switching mode selection logic.
The protection blocks on the right monitor VOUT for overvoltage, the LED pins for short-circuit conditions, and junction temperature for thermal protection. All faults are reported through a dedicated register accessible over I2C.
The breakout board is designed to be flexible, and it is possible to populate different IR LED types according to the application to be evaluated. For my setup, the SFH41747 LEDs were already assembled on the main board, and additional external LEDs were promised to be provided later. However, in the kit, only pre-mounted LEDs are included.
It connects to J1 on the main EVK through an 8-pin header. A very important note: when the breakout board is connected, J5 on the main board has to be removed to disconnect the LEDs assembled on the main board.
The kit includes an official ESP32-S2 DevKit M1board from Espressif.
I am familiar with ESP32 modules, but I was glad to see it included in the EVK kit. It means you have a I2C controller right out of the box, with no need to connect any other microcontroller.
The ESP32-S2 serves as a bridge between the PC GUI and the AS1170. It handles the I2C master communication and also generates the STROBE signal that triggers flash pulses. The module connects to the EVK board via two multi-pin headers (J2 and J3). When the micro-USB cable is plugged into the ESP32-S2, it provides 3.3 V to the EVK board through jumper J6 — a detail that is important to understand before changing any power configuration.
For detailed understanding of the ESP32-S2 board layout and GPIO capabilities, the following reference diagrams are included.
Figure 3.2: ESP32-S2 pinout diagram highlighting GPIO functions, peripherals, and signal mapping.
Small detail, but I appreciated the branded cable rather than a generic throwaway. It is the kind of small quality signal that tells you a manufacturer cares about the full experience.
This was the first real hands-on step, and I want to walk through this step exactly as I did it, because the order matters, and you'll be left with an empty GUI wondering what went wrong if you skip this step.
| GUI and Driver Installation |
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Step 1: Go to this Github repository and download the AS1170_GUI_v1.exe |
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Step 2: Download the require CP210x VCP Drivers – Silicon Labs |
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Step 3: Attach Eps32 with main Board and connect it to PC using USB 2.0 Type-A to Micro-B cable |
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Step 4: Open Device Manager and search for “USB to UART Bridge” |
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Step 5 : “Update Driver” from your local drive and select folder of step #1 (location of extracted SW package) |
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Step 6 : Driver is successfully installed launch AS1170_GUI.exe |
Having successfully connected the GUI and confirmed the chip ID, I now proceeded to test each operating mode individually. This was the part that I was most looking forward to. I was eager to actually drive the IR LEDs and see what this device was capable of.
Indicator mode uses the 6 LSBs of the LED current registers and applies a 31.25 kHz PWM modulation. This is designed for applications like always-on proximity sensing or low-power face tracking where the LED needs to run continuously but at reduced average current.
I configured it as follows: selected "Indicator Mode/PWM" in the Operation Mode section, set Indicator PWM to 4/16 (25% duty cycle), LED 1 Current to 199.5 mA, LED 2 Current to 199.5 mA, then checked "Out On".
Figure : AS1170 GUI configured for indicator mode PWM, with 25% duty cycle, 199.5mA per LED channel, Out On enabled.
According to the EVK user guide, this will drive approximately 400mA at a duty cycle of 25% with a PWM frequency of approximately 30.6 kHz on the LED OUT pins. Pointing the camera at the IR LED, I can see the IR LED lighting up. This is due to the camera's sensor, which can detect near-infrared light, not visible to the human eye.
Flash mode is the high-power mode of operation in which the full range of the LED current register is utilized. I selected Flash Mode and left the current settings at 199.5 mA per channel. I then set the LED ON Time to 2 ms.
With "Out On" checked and "Auto Strobe" selected, I pressed the S1 button on the EVK board, and the IR LED emitted a flash pulse.The IR LED emitted a flash pulse corresponding to the configured 2 ms timing, as expected from the AS1170 configuration.
Figure: AS1170 GUI in Flash Mode 2 ms LED ON Time, 199.5 mA per channel.
I recall when I first pressed the S1 button for the first time in flash mode and how nice it was to get the perfectly timed IR burst triggered by the physical button with no code written at all. This is the kind of workflow that makes a well-designed EVK so valuable.
Assist light mode is situated between flash and indicator modes in terms of current range. Assist light mode utilizes the 7 least significant bits of the LED current registers. This limits it to half the maximum flash mode current. This mode is applicable in torch/video light applications where the LEDs operate continuously but at lower intensity than in flash mode. I configured this mode and checked that the LEDs emitted light steadily, which I could see via the camera.
The GUI has a Fault Indication section where OV Protection, LED Short, and Over Temp are indicated by coloured LED indicators. There are also status indicators for Timeout and UVLO. Pressing the "Read" button to read the registers confirmed that there were no faults recorded during the tests. The "Reset" button resets the fault register, which is essential because the AS1170 holds faults latched until they are reset by the I²C readout process. This is noted in the documentation of register 0x08.
What I think is particularly nice here is that with the GUI, the fault register is actually very easy to monitor. You don’t necessarily need an oscilloscope or a serial terminal to see what’s being reported by the chip. That’s actually very nice in terms of early-stage bring-up.
In my case, the most frustrating problems I experienced were not with the hardware performance or the general functionality, but with the GUI. All other aspects of this setup seemed to be quite clear and easy to work with. However, the GUI was not consistent and caused problems with the workflow.
The problems I experienced with this setup were mainly evident during long periods of testing. I have identified two major problems:
1. Configuration Panel Does Not Open
Sometimes, clicking the button to open the configuration panel did not work. There was no error message, no signs of activity. It was just not working. This is very confusing since it is not clear whether the command was registered or not. The only solution I found was to restart the system. This is not very efficient and is very frustrating.
2. Chip Detection and Control Does Not Function
Sometimes, the system was not able to detect the chip ID. This meant that the system was not in control of the main board. Although the interface was still working, it was not possible to do anything with it. No commands were registered, and no interaction was possible.
The next stage of my analysis was to go beyond the use of the vendor GUI and directly connect to the AS1170, emulating the way the device will perform in a real-world embedded system using the ESP32-S2 DevKit M1 supplied with the kit.
One of the best things about the kit is that ams OSRAM did not constrain the evaluation process to only software on the PC side but included an ESP32-S2 DevKit that can directly talk to the evaluation board.
Hardware Interface
This particular hardware interface was surprisingly simple.
The DevKit M1 provided with the kit is intended to work with the AS1170 EVK via the onboard headers, so there is no need for wiring the connection yourself or placing the components on a breadboard just to check the functionality.
The protocol used to talk to the AS1170 is I²C and its characteristics according to the documentation:
Standard Mode: 100 kHz
Fast Mode: 400 kHz
My implementation uses fast-mode I²C communication at 400 kHz, which is perfectly sufficient for embedded control tasks.
The ESP32 is connected to the AS1170 using the following lines:
SDA → GPIO 12
SCL → GPIO 13
I²C Slave Address → 0x30
As you can see, the EVK itself comes pre-configured with the correct pull-ups.
To test firmware code, I used Arduino IDE version 2.x.
The configuration steps were simple:
No additional libraries were necessary besides standard Arduino libraries
The code includes:
Instead of working with a simplified demo sketch, I analyzed the real register-level firmware implementation given.
It’s significant because it represents something far more useful than checking that the chip acknowledges on the bus; rather, it shows how you can have full, low-level control over the AS1170 just like an embedded program would.
The code accesses the registers of the AS1170 through I²C communications.
The slave address is configured as:
#define _slaveaddress 0x30
And I²C initialization is performed as:
Wire.begin(SDA_PIN, SCL_PIN, CLOCK_SPEED);
with:
#define SDA_PIN 12 #define SCL_PIN 13 #define CLOCK_SPEED 400000
The value of this approach was its ability to provide access to critical control registers within the AS1170 system.
The firmware interface enables interaction with:
| Register | Address | Function |
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| Fixed ID | 0x00 | Device identification |
| LED1 Current | 0x01 | Set output current for LED channel 1 |
| LED2 Current | 0x02 | Set output current for LED channel 2 |
| Flash Timer | 0x05 | Configure flash timeout duration |
| Control Register | 0x06 | Select operating modes |
| Strobe Signaling | 0x07 | Configure strobe behavior |
| Fault Register | 0x08 | Monitor device protection status |
| PWM / Indicator | 0x09 | Configure PWM indicator operation |
This effectively exposes most of the core functionality of the AS1170 without needing the GUI.
Using this implementation, I was able to directly access functionality such as:
This is precisely the sort of control expected in a real embedded deployment.
Communication is achieved using the Arduino Serial Monitor.
Command structures are simple.
For instance:
Reading all registers
read
Results in:
write,1,100,0
This writes a new value to register 0x01.
write,2,120,0
write,5,20,0
write,6,value,0
This allows experimentation with operating modes.
reset
This was a particularly useful part of the roadtest in confirming that AS1170 isn't just another GUI-oriented demo board, but an actual embeddable solution.
I²C communications were stable, register reading was flawless, and the firmware successfully gave meaningful control over the device.
In comparison to the GUI, it feels much more natural as product integration.
Instead of using vendor software, you control a subsystem from your firmware by clicking buttons.
However, the API is quite low level.
It is not intended as a high-level abstraction:
However, for this kind of evaluation, this wasn't really a downside as we got insights on how the device can be controlled in firmware.
From the perspective of an embedded engineer, this was one of the most exciting parts of the roadtest.
There are many eval boards that end up being nothing more than demos stuck within the vendor software ecosystem.
Not this one.
It worked exactly as any good embedded peripheral board should work:
This makes it a potentially useful device in:
This exercise for me was an experience in which the AS1170 went from being "an evaluation board with a nice GUI" to actually being useful for embedded software development.
The difference is important.
GUI shows functionality.
Register manipulation shows product readiness.
One of the most rewarding aspects of any IR LED driver evaluation is seeing this invisible light in action. As the AS1170 driver is designed to drive near-infrared LEDs (with the SFH41747 emitting at approximately 850 nm), this light is invisible to the naked eye but perfectly within range for detection by most digital camera sensors.
I used a digital camera on a laptop. I aimed this camera directly at the IR LED package. In Indicator mode at 400 mA combined current and 25% duty cycle, the IR LED was visible on the camera preview as a bright white/purple spot – very visible and unmistakable.
The EVK document includes a comparison shot of the ams-OSRAM IR LED versus a competing IR LED product under the same conditions (400 mA, 25% duty cycle). The ams-OSRAM IR LED emits a much brighter light in the camera preview – again, in agreement with its much higher optical efficiency in comparison to the competing product’s IR LED chip used in this product – the SFH41747.
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Figure 13: Side-by-side comparison showing the ams-OSRAM SFH41747 (left, brighter) versus a competitor LED (right) under identical conditions — 400 mA, 25% duty cycle.. |
Having tested the AS1170 EVK in practical embedded applications, I felt that a comparison with the other commonly available solutions for IR LEDs and flash drivers could help me understand more about this device. I was not interested in just comparing technical specifications; rather, I wanted to look at practical issues like integration, versatility, safety features, etc.
| Feature | ams OSRAM AS1170 EVK | TI LM36011 | TI LM3644 | Generic MOSFET IR Driver |
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| Target Application | IR LEDs / VCSEL / Embedded sensing | IR illumination | Camera flash + IR | Basic LED switching |
| Channels | Dual-channel | Single-channel | Dual-channel | Usually single |
| Max Current Capability | Up to 1 A per channel | High-current flash capable | High-current flash capable | Depends on MOSFET |
| Control Interface | I²C + PWM + Strobe | I²C | I²C | PWM / GPIO only |
| Integrated Boost Converter | Yes | Yes | Yes | No |
| External MCU Integration | Very flexible (ESP32 tested) | Moderate | Moderate | Manual implementation |
| GUI Support | Dedicated PC GUI included | No dedicated GUI | No dedicated GUI | No |
| Protection Features | Thermal, UVLO, LED short, timeout | Thermal + protection | Thermal + protection | Usually none |
| Ease of Evaluation | Very developer-focused | IC-focused | Mobile-focused | DIY level |
| Best Use Case | 3D sensing, face unlock, IR systems | IR flash | Smartphone flash | Simple IR LEDs |
| Real-World Impression | Most complete evaluation platform among compared options | Strong IC but less evaluation-friendly | Optimized mainly for mobile camera flash | Cheap but lacks precision and protections |
First and foremost, it’s worth noting that at its heart, the AS1170 is a current mode boost converter with precision current sink capabilities. The VIN pin is used to connect up a battery voltage that ranges over a typical range of 2.7 V to 4.4 V. The boost converter kicks this up to whatever voltage is required on VOUT to make sure that the LED voltage is always covered, while the precision current sink on LED_OUT1 and LED_OUT2 absorbs the LED current and regulates it to whatever was set in the current registers.
The boost converter runs at a fixed 4 MHz. This is fast enough to allow very small inductors to be used – in this case, 1µH – but not so fast that EMI becomes a serious issue in RF circuits in a smartphone. The on-resistance of both the internal PMOS and NMOS switches is around 70mΩ – nice and low so that power is not wasted in these switches even at ampere-scale currents.
led_current1 and led_current2 are 8-bit registers. From the register map above, current steps are 3.5 mA per LSB. The current is 551 mA per channel by default, as 0x9C is the default register setting. Setting both to 0xFF will get 900 mA per channel or 1800 mA total in flash mode with current_boost = 0, or 2000 mA total with current_boost = 1.
There are operating modes, each of which has a current cap for the same register. In indicator/PWM mode (mode_setting = 01), only 6 bits of the register are used to cap current at 222.4 mA per channel. In assist light mode (mode_setting = 10), 7 bits of the register are used to cap current at 448.2 mA. In flash mode (mode_setting = 11), all 8 bits of the register are used to get up to 900 mA.
From the datasheet, Figure 4 is a plot of DCDC converter efficiency vs. VVIN (input voltage), for various levels of LED current. The important takeaway here is that at a typical 3.7 V Li-ion battery voltage, efficiency will remain within 90-95%. This drops significantly for lower voltage – lower than 3 V – which is why there is an undervoltage current reduction feature.
Figure: AS1170 DCDC efficiency versus input voltage for various LED current configurations. Peak efficiency exceeds 95% at 3.7 V input with 1000–1300 mA load.
From the datasheet, it can also be noted that Figure 5 indicates application efficiency, or rather, the efficiency in delivering power to the LED divided by the power being drawn from the supply. This is a much more useful figure, as it includes both the losses of the boost converter and the voltage drop across the current sink. With an application efficiency of 80-85% at 3.7 V, this means that for every 1W being drawn from the battery, 800-850 mW will actually get to the LED. This is a really impressive efficiency for a device of this complexity and size.
Figure 6 in the datasheet shows battery input current versus VIN. What stands out here is that as input voltage drops (representing a discharging battery), the input current increases to maintain the same LED output power. This is the natural behaviour of a boost converter. At 2.8 V input with 2000 mA combined LED output, the battery current approaches 4 A — a number worth knowing when evaluating connector and trace sizing in a real product.
From the datasheet, it is clear that Figures 8 and 9 depict the LED current startup waveforms for 1.0 A and 800 mA, respectively. It is clear that the soft-start ramp is included, as the current does not change abruptly. Instead, it increases gradually over a period of 250 to 1000 µs. This is done internally to prevent a sudden surge in current, which would cause a voltage glitch. This is particularly important in RF environments, such as in smartphones, where noise is a critical factor
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Figure 8: AS1170 LED current startup waveform at 1.0 A — the soft-start ramp smoothly brings the LED current to its target value over approximately 500 µs, preventing supply voltage transients. |
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Figure 9 shows the ramp-down waveform, which also performs smoothly. The ramp-down time is 500–1000 µs. Together, these controlled edges are what make the AS1170 suitable for camera flash applications where abrupt current switching could create visible artefacts in captured images. |
As the current through the LEDs ramps up, the AS1170 monitors the voltage across the LEDs. If a short is detected, the voltage across the LEDs will be very close to zero. Therefore, this voltage should be less than the VLEDSHORT threshold of 1.0V. Once a short is detected, the boost converter is turned off, the current sinks are turned off, and the fault_led_short bit in the fault register is set.
In a dual-LED system, if only one of the LEDs is shorted, then this LED is disabled and the part continues to operate with the good LED. This is a resilience feature that is actually useful in a production part.
Of course, the AS1170 is not simply a device for hobbyists. It's a precision device for high-end applications. As I was reading through the application notes, I found myself wondering how many products I currently use that probably contain a device very similar to this working behind the scenes.
Today’s smartphones make use of a VCSEL flood illuminator to flood the face with near-infrared light and a dot projector for structured light, and these devices need high-precision, high-current pulsed light. The flash mode and strobe control of the AS1170 make it perfectly suited for these applications, as the processor configures the current and then fires individual flash pulses in sync with the camera frame capture, ensuring the IR light is only on for the time required for each frame of the depth map.
In the case of 3D cameras, which make use of a projector to send patterned infrared light, and then capture the distorted light to calculate depth, the ability to trigger from an external STROBE pin with sub-millisecond accuracy (flash timeout accuracy ±7.5%) makes the AS1170 perfectly suited for illumination in these devices. The auto_strobe = 1 mode is particularly relevant to this application, as it enables frame-by-frame illumination without any communication overheads between frames.
For fixed-mount IR illuminators used with security cameras or face recognition terminal applications, an IR device is needed that can operate continuously in Assist Light mode. The AS1170's over-temperature protection, together with automatic current reduction when the device approaches its maximum operating temperature, makes it an appropriate device for these applications.
In barcode readers or other industrial scanners, the illumination cycle is often directly associated with the scan trigger. The AS1170's strobe trigger mode, together with its ability to drive two separate LED channels, makes it an appropriate device for applications where different illumination angles or intensities are needed for different scan targets.
For proximity and obstacle detection in robots, the AS1170 may be used to drive IR LEDs in the indicator/PWM mode with a moderate continuous current for always-on illumination of IR sensor arrays. The I²C interface enables the main MCU to adjust illumination intensity according to ambient conditions or power budget constraints.
Upon analyzing data sheets, reference design and actual implementation considerations, I identified that the AS1170 EVK occupies its unique position, unlike many other LED driver products. Although such components as the TI LM36011 or LM3644 are very well optimized for applications in smartphone flash systems, AS1170 EVK appears to be far more flexible and development-friendly for experimenting with IR embedded systems.
The most notable aspect of AS1170 EVK during comparative analysis is the combination of hardware flexibility with ease of software programming. The availability of GUI, external LED connections, ability to program strobes, two-channel configuration and connectivity to ESP32 microcontroller make the platform far more convenient than using any driver ICs and MOSFET drivers.
When comparing the platform to simple MOSFET driver circuits, one can notice significant improvements in terms of better current regulation, higher level of safety, better timing accuracy and additional protection against overheating, low voltage conditions and LED faults. As for generic LED drivers, most of them are capable of producing high current levels, however, they are rarely optimized for IR pulses.
Taking an engineer’s point of view, the AS1170 EVK seems to be a platform for prototyping rather than just a simple eval kit. This is due to features such as controllability, high current handling, boost topology, and the inclusion of tools designed by developers that make this module very useful in areas including 3D sensing, facial recognition, machine vision, robotics, and optics in embedded systems.
This evaluation was particularly fascinating because I got to see that, despite its apparent simplicity, the IR LED driver is at the very heart of some really complex technology that we use all the time but never really think about.
Despite not yet having received my extra LEDs, I'm definitely planning on testing out the breakout boards and doing something productive with them when they come in. Stay tuned!
