https://community.element14.com/challenges-projects/element14-presents/workbenchwednesdays/The Bald Engineer 3D prints, laser cuts, and solder things that beep, blink, and fly. Learn the tools on his bench, rant on capacitor types, and watch tutorials for everyone.en-USTelligent Community 12https://community.element14.com/challenges-projects/element14-presents/workbenchwednesdays/w/documents/71912/powering-your-projects-reviewing-multicomp-pro-mp711001-bench-power-supply----workbench-wednesdays-89Thu, 01 May 2025 14:50:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:21dbce94-c489-4ab2-b667-853599ff2f13e14philIn this episode of Workbench Wednesdays, James reviews the Multicomp Pro MP7110001, a four-channel linear bench power supply delivering over 340W of output. He walks through its key features, including a 4.3" display, digital I/O control, built-in serial and parallel channel switching, and user-defined presets. The video includes practical performance tests such as ripple voltage, turn-on skew, and maximum power output. James also notes the absence of remote sensing and shares insights into real-world usage. Watch the full review to see how this supply performs on the bench. Watch the Review https://youtu.be/gmLBOIHM4DU James delves into a comprehensive review of the Multicomp Pro MP711001 Linear Bench Power Supply, uncovering its versatile features, user-friendly interface, and robust performance. The Multicomp Pro MP711001 proves to be a versatile unit that seamlessly integrates into both professional labs and hobbyist setups. Plus, it is very powerful. MP711001 Overview This linear supply boasts an impressive power output of 348 watts across all its channels. Channels 1 and 2 can deliver up to 172 watts each, while channel 3 can output a maximum of 19 watts. The fourth channel, an always-on USB port, adds flexibility. The MP711001 measures 355 by 240 by 168 millimeters and weighs just under 11 kilograms. Its front panel features a bright, easy-to-read 4.3-inch display with several readouts. The keypad makes it quick and easy to enter voltage and current values. Each of the variable channels has its own select button and power enable. There is a main switch that controls all three variable supplies simultaneously. On the back are ports for remote interfacing through RS-232, LAN, and a USB device. A digital I/O port lets you enable channels with external signals or provides output signals based on conditions you set through the user interface. The USB host port accepts drives to save data from the recorder or data logging features. The MP711001 linear bench power supply supports constant voltage (CV) and constant current (CC) modes. In CV mode, the power supply maintains a constant voltage output regardless of the load, while in CC mode, it maintains a constant current output. Each variable channel also has overcurrent protection (OCP) and overvoltage protection (OVP), which are safety features that prevent the power supply from delivering too much current or voltage, respectively. In the main part of the review, James conducts several tests to showcase the power supply's capabilities. He tests the ripple voltage performance and the turn-on skew between channels and verifies the maximum output power capability. The ripple voltage measurement used a 10 ohm (25-watt) power resistor and oscilloscope. A resistor provides more stability than an electronic load since the load will adjust its reactance based on the output voltage. Sometimes, an electronic load can cause more ripple than the supply actually has. The MP711001's ripple, or regulation, is specified up to 1 MHz with less than 2 millivolt peak-to-peak (mVpp). Using a 1 MHz (digital) filter on the oscilloscope, James demonstrated that the supply ripple was only about 1 mVpp when outputting 25 watts. Even though he did not use a power rail probe, he felt the measurement agreed with the datasheet. FPGA development boards often have several voltage rails and a specific order in which they need to turn on. So, for the next test, James checked to see how much skew each channel had when activated simultaneously. It turns out Channel 3 activates first, followed by 1 and then 2. The channels exhibit some jitter with each turn-on. However, the order always seems to be the same. The skew between channels 3 and 1 is about 10 milliseconds, while the skew between 1 and 2 is less than 2 milliseconds. These values are consistent enough that they should be suitable for sequenced turn-on requirements. The last test is what James called his "most ridiculous test ever." Using three electronic loads, including the AIM TTi SMU4002, he loaded the MP711001 bench supply with 340 watts. The result was impressive. The peak-to-peak voltage on one of the channels was similar to the 25-watt loading. James has no reason to suspect that the supply couldn't make it all the way to 348 watts. As a side note, a Kill-A-Watt meter measuring the 120 Vac mains side of the supply showed the bench supply drew about 5.3 amps during this test! James summarizes his thoughts as the video wraps up, recommending the Multicomp Pro MP711001. He highlights its user-friendly interface, robust protection features such as overcurrent protection (OCP) and overvoltage protection (OVP), and solid performance as reasons why it stands out in a crowded space. The Multicomp Pro MP711001 Bench Power Supply is a well-rounded tool that delivers on its promises. Whether you're working on intricate electronics projects or simply need a reliable power supply for general use, this device is a worthy addition to your workbench. Bill of Materials Product Name Manufacturer Quantity MP711001 - Bench Power Supply, Programmable, 4 Output, 0 V, 32 V, 0 A, 5 A Multicomp Pro 1 Buy Now Additional Links 3 Advanced Electronic Load Measurements with the Multicomp Pro DC Load - Workbench Wednesdays 71 How to Measure Ripple Voltage on a Switch-Mode Power Supply - Workbench Wednesdays 51 How to Program Test Tools with Python - Workbench Wednesdays 66 element14 Presents | About James | Workbench Wednesdayselectronic load testingconstant voltage power supplypower supply skew testlab power supplyconstant current power supplybench power supplylinear power supplymp7110001 reviewpower supply ripple testmulticomp pro mp7110001workbench wednesdaysprogrammable power supplydigital i/o bench supplyfour channel power supplypower supply for electronicshttps://community.element14.com/challenges-projects/element14-presents/workbenchwednesdays/w/documentsThu, 01 May 2025 14:50:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:faa056aa-4fca-4dc5-8c73-ec23c9849e53https://community.element14.com/challenges-projects/element14-presents/workbenchwednesdays/w/documents/71910/can-polymer-capacitors-replace-mlccs-in-power-converters-a-comparative-test----workbench-wednesdays-88Wed, 16 Apr 2025 09:19:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:c43786e9-a931-4cd3-9458-d89af8878be8vijeth_dsJames explores whether multilayer ceramic capacitors (MLCCs) can be replaced with polymer electrolytic capacitors, specifically KO-Caps, in a DC-to-DC converter. He compares the performance of both capacitor types, discussing the MLCC's DC Bias Effect, which reduces capacitance under load, and how KO-Caps avoid this issue. Through a series of tests on an evaluation board, James measures ripple and capacitance in various configurations and highlights the trade-offs between MLCCs and polymers in terms of performance, cost, and board space. Ultimately, the video offers insights into when it might make sense to switch from ceramics to polymers in power conversion designs. Watch the Video to find out! https://youtu.be/r73H-SSi8dE In this video, James explores whether multilayer ceramic capacitors (MLCCs) can be replaced with polymer electrolytic capacitors with the help of a DC-DC converter. He begins by discussing the characteristics of MLCCs and polymers. Using an off-the-shelf DC-to-DC converter evaluation board as the test setup, James demonstrates how the performance of both types of capacitors can be evaluated. James explains that MLCCs comprise alternating layers of dielectric material (Barium Titanate) and metal (Nickel), forming tiny capacitors in parallel. The multiple layers give the overall device a relatively high capacitance. One of the advantages of MLCCs is their low equivalent series resistance (ESR), which is attributed to the parallel metal layers. However, he notes that class 2 and 3 MLCCs, such as those with X7R or Y5V ratings, experience a significant loss in capacitance when exposed to DC voltage, an effect commonly known as the "DC Bias Effect." He illustrates this effect by showing measurements of a 22-microfarad MLCC rated for 10 volts. When 50% of the rated voltage is applied, the capacitance drops to 6.7 microfarads, and at full voltage, the capacitance is reduced by over 85%! In contrast, polymer electrolytic capacitors, or KO-Caps, as KEMET calls them, Are made with a tantalum anode, tantalum pentoxide dielectric, and a conductive polymer cathode (PEDOT). They do not suffer from the same DC Bias Effect. These capacitors offer high capacitance and low ESR without the voltage coefficient, which makes them attractive as replacements for MLCCs in some applications. James provides a detailed overview of the test setup, which involves an evaluation board used in a DC-to-DC converter experiment. The capacitors are strategically positioned near the MOSFETs and output terminals. The equipment used in the test includes a low-noise oscilloscope, electronic load, linear power supply, and 10:1 oscilloscope probes. James begins by testing the original configuration of four 100-microfarad MLCCs and measuring the ripple at different current loads. He finds that the ripple ranges from 132 to 151 millivolts, which becomes the baseline for the rest of the comparisons. Next, he swaps the MLCCs for KEMET's KO-Caps, keeping the rated capacitance precisely the same and the physical size roughly the same as the originals. Running the same previous tests, James finds that the ripple in the polymer setup is only a few percent higher than the MLCC configuration, suggesting no immediate advantage in replacing MLCCs with KO-Caps. However, James points out a critical difference: the MLCC configuration includes polymers on the back side of the board, near the output terminals, while the KO-Cap configuration does not. This subtle difference, he argues, could explain why the KO-Caps performed so similarly to the MLCCs. James removed the bulk polymer capacitors from the MLCC setup to investigate further and reran the tests. Without these bulk polymers, the ripple skyrockets to several volts, demonstrating that the MLCCs alone are insufficient to stabilize the power supply. He concludes that while high-capacitance MLCCs can offer low ripple, they are not a standalone solution in this specific setup. James then compares the cost of the different configurations. He notes that the price of high-capacitance ceramics is often comparable to that of polymer capacitors. However, the KO-Cap solution, despite having a (very) slightly higher ripple, costs nearly 60% less than the ceramic plus polymer solution! Additionally, when James adds two bulk 470-microfarad polymers to the KO-Cap setup, the ripple drops by 45%. The total solution is still cheaper than the original MLCC-plus-polymer setup. This finding suggests that KO-Caps can provide a cost-effective alternative in some cases. In the concluding section, James emphasizes that while polymer capacitors may offer advantages in specific applications, they come with trade-offs. MLCCs must be carefully evaluated for their DC Bias Effect, as their effective capacitance can drop significantly in real-world applications. Additionally, polymer capacitors tend to have larger footprints compared to MLCCs, so you should consider board space when making their selection. He also warns that polymers behave differently at higher frequencies and that their ESR changes as the frequency increases. Overall, James's evaluation shows that while MLCCs and polymers have their respective strengths and weaknesses, polymers can serve as a viable replacement in specific designs, particularly when considering cost and board space constraints. The key takeaway is that you must carefully consider their requirements, such as ripple tolerance, size, and cost, when choosing between MLCCs and polymer capacitors. Downloads and Links Learning About Polymer Capacitors -- The Learning Circuit 40 Ceramic Capacitor Voltage Effect - Workbench Wednesdays 30 Kemet KSIM WBW88 Additional Data - Screenshots and detailed outputs Bill of Materials Product Name Manufacturer Quantity Buy Kit C1206C107M9PACTU SMD Multilayer Ceramic Capacitor, 100 µF, 6.3 V, 1206 [3216 Metric], ± 20%, X5R YAGEO (KEMET) 1 Buy Now T520A107M006ATE025 Tantalum Polymer Capacitor, 100 µF, ± 20%, 6.3 V, A, 0.025 ohm, 1206 [3216 Metric] YAGEO (KEMET) 1 Buy Now element14 presents | About James | Workbench Wednesdayscapacitor cost comparisonkemet ko-caps reviewmlcc capacitance under loadpolymer electrolytic capacitor advantagesmlcc vs polymer capacitorsdc-dc converter capacitor comparisonlow esr capacitor typespower supply capacitor selectionpolymer capacitors for dc-dc convertersmlcc ripple voltage teste14-yageodc bias effect in mlccsworkbench wednesdaysko-caps capacitor performancereplacing mlccs in power designmlcc voltage coefficientbulk polymer capacitor benefitshttps://community.element14.com/challenges-projects/element14-presents/workbenchwednesdays/m/files/150232Fri, 11 Apr 2025 16:56:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:f1b1f2a1-92b0-4cdb-9317-f94c90336883cstantonAdditional data for Workbench Wednesdays episode 88 Contains: 03 - added qty2 470u to output\named\15A MLCC with C28.png 03 - added qty2 470u to output\named\15A MLCCs-qty4 - 470u-qty2 Screenshot_2024-09-09_4_143144 - Copy.png 03 - added qty2 470u to output\named\15A T520A-qty4 - 470u-qty2 Screenshot_2024-09-09_9_144806 - Copy.png 03 - added qty2 470u to output\named\300mA MLCC with C28.png 03 - added qty2 470u to output\named\3A MLCC with C28.png 03 - added qty2 470u to output\Screenshot_2024-09-09_0_142806.png 03 - added qty2 470u to output\Screenshot_2024-09-09_1_142936.png 03 - added qty2 470u to output\Screenshot_2024-09-09_2_143038.png 03 - added qty2 470u to output\Screenshot_2024-09-09_3_143054.png 03 - added qty2 470u to output\Screenshot_2024-09-09_7_144630.png 03 - added qty2 470u to output\Screenshot_2024-09-09_8_144728.png 03 - added qty2 470u to output\Screenshot_2024-09-09_9_144806.png 06 - T520A-qty4 - no C2 or C8\330mA T520A-qty4 - no C2 or C8.png 06 - T520A-qty4 - no C2 or C8\3A T520A-qty4 - no C2 or C8.png 06 - T520A-qty4 - no C2 or C8\15A T520A-qty4 - no C2 or C8.png 07 - T520A-qty2 - no C2 or C8\330mA T520A-qty2.png 07 - T520A-qty2 - no C2 or C8\3A T520A-qty2.png 07 - T520A-qty2 - no C2 or C8\15A T520A-qty2.png 08 - T520A-qty2 - T520V100 on C2 and C8\330mA T520A-qty2 - T520V100 on C2 and C8.png 08 - T520A-qty2 - T520V100 on C2 and C8\3A T520A-qty2 - T520V100 on C2 and C8.png 08 - T520A-qty2 - T520V100 on C2 and C8\15A T520A-qty2 - T520V100 on C2 and C8.png 09 - T520A-qty2 - T520Y470-qty2\330mA T520A-qty2 - T520Y470-qty2.png 09 - T520A-qty2 - T520Y470-qty2\3A T520A-qty2 - T520Y470-qty2.png 09 - T520A-qty2 - T520Y470-qty2\15A T520A-qty2 - T520Y470-qty2.png YAGEO Polymer vs. MLCC Comparison 150 kHz Measurements.xlsxWorkbench Wednesdays 88https://community.element14.com/challenges-projects/element14-presents/workbenchwednesdays/w/documents/71905/hands-on-with-aim-tti-s-smu4000-series-source-measurement-tools----workbench-wednesdays-87Wed, 02 Apr 2025 12:34:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:68ac3329-d76b-4081-b2a0-b32b986f734be14cstantonThe AIM TTi SMU4000 family are compact source measurement units (SMUs) rated for 25 watts. One model handles up to 21 volts, while another does 21 and 210 volts. Both can source or sink up to 3.15 amps. Using a technology called PowerFlex, this power rating is usable across most of the SMU4000's range. This video also shows how it can act as a voltmeter and ohmmeter and measure the leakage current of a capacitor. Watch the Aim-TTi SMU4000 Family Review Video https://youtu.be/cAvjQb6t2gI The AIM TTI SMU4001 is a powerful instrument that combines a bench power supply, electronic load, and high-precision digital multi-meter. James demonstrates the unit's capabilities and takes a few measurements. There are two AIM TTI SMU4000 models available. Each offers 25 watts. The difference is their maximum voltage rating. One model (SMU4001) supports up to 21 volts, while the other (SMU4201) can reach up to 210 volts. Besides the extended voltage range, the two units have the same capabilities and features. The first thing James noticed about the SMU4001 was its size. Despite its multi-functionality, it is the same size as a typical benchtop multimeter or switching bench supply. (These units are half a rack width and 2U tall.) The front panel features 4-wire inputs, a control knob, and a touch screen, which simplifies navigation and operation. The touch screen is especially user-friendly, making it easier to adjust settings compared to just the knob alone. James shows the remote/automation ports, a digital IO port, and rear voltage/sense terminals on the back of the SMU4001. The rear terminals feature a convenient push-and-release mechanism, reducing the risk of losing adapters—something James has encountered with other instruments. As a source, the SMU4001 can output up to 25 watts, with a current limit of 3.15 amps and a voltage range of up to 21 volts. This capability is maintained across most of its voltage range, ensuring consistent performance regardless of the specific output settings. AIM TTi calls this capability PowerFlex. The SMU4001 also features an adjustable slew rate, allowing for fine-tuning of the response time to suit various applications. Additionally, the SMU4001 offers a high reactance load stability option, ideal for working with reactive loads such as motors or large capacitors. James demonstrates how the high reactance mode affects a large (4700 uF) capacitor. In load mode, the SMU4001 can operate in constant current, resistance, or power mode and can sink up to 3.15 amps. This capability makes it an excellent tool for tasks like measuring battery capacity. James demonstrates this by discharging a 350 milliamp-hour LiPo battery at 525 milliamps until it reaches a cutoff voltage of 3 volts. This measurement takes about 29 minutes to complete, meaning the battery provides about 262 mAh under these conditions. However, James noted that he had to manually calculate the capacity since no "energy" measurement was available. The SMU4001's measurement capabilities are comparable to those of a high-end bench DMM, offering voltage, current, and resistance modes. Additionally, the SMU4001 includes advanced measurements such as insulation resistance and leakage current, which is particularly useful when testing passive components like capacitors. For example, a ceramic capacitor might show an insulation resistance in the range of hundreds of megaohms, while an electrolytic capacitor, being more leaky, would have a lower insulation resistance. The SMU-Link accessory allows two SMU4001 units to be connected, effectively creating a two-channel instrument. This setup is ideal for characterizing active devices like MOSFETs, where one unit controls the gate, and the other monitors the drain. In conclusion, James found the AIM-TTI SMU4001 to be a versatile, powerful SMU that combines the functions of a power supply, electronic load, and digital multimeter in a compact package. Its ability to maintain full power across a wide voltage range, coupled with features like adjustable slew rate and high reactance mode, makes it a powerful tool in any lab. Whether characterizing components, measuring battery capacity, or simulating device loads, the SMU4001 provides the precision and functionality needed for accurate and reliable results. Where to Buy Aim-TTi Source Meters Product Name Manufacturer Quantity Buy Kit SMU4001 - 21V Source Meter / Unit, 1 Channels, SMU4000 Series, Current/Voltage Measure, Current/Voltage Source AIM TTI 1 Buy Now SMU4201 - 21V, 210V, Source Meter / Unit, 1 Channels, SMU4000 Series, Current/Voltage Measure, Current/Voltage Source AIM TTI 1 Buy Now element14 presents | About James | Workbench Wednesdaysbattery capacity measurementhigh reactance load stabilityaim tti smu 4001aim tti smu4000bench power supplypowerflex technologysource measurement unit (SMU)electronic load testerhigh-precision multimeteradjustable slew rate power supplyemu for capacitor testingleakage current measurementworkbench wednesdaysinsulation resistance testinglab testing equipmentmosfet characterizationhttps://community.element14.com/challenges-projects/element14-presents/workbenchwednesdays/w/documents/27854/how-to-pick-replacement-electrolytic-capacitors---workbench-wednesdays-63Mon, 16 Sep 2024 13:33:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:1e4099d8-8798-4fda-8251-7e2d3bce37f3cstantonAluminum (or aluminium) electrolytic capacitors have a chemical layer that has known wear-out mechanisms. Eventually, they need to be replaced. To make matters worse (or better?) there are many different options! Learn why aluminum electrolytic capacitors wear-out and how to pick their replacements in this video. Watch the Video: www.youtube.com/watch Supplemental Content: The Learning Circuit 40: Learning About Polymer Capacitors The Learning Circuit 42: Replacing MLCCs with Polymer Capacitors Workbench Wednesday 04: Capacitor Replacement on a Commodore 64 - A Lesson in Through-Hole Soldering Episode 535: Repair a Sega Game Gear - How Hard Can It Be? Bald Engineer's Electrolytic Flow Chart Axial Polymer BAC Adapter Selecting electrolytic capacitor replacements (for a TRS-80 Model 100) [Full Video] Twitch Livestreams TRS 80 Model 100 re-cap: Remove the caps | Part 1 Installing the replacement capacitors into the Model 100 | Part 2 Bill of Material: Product Name Manufacturer Quantity Buy Kit 35ML10MEFC4X7 Aluminium Electrolytic Capacitor, ML Series, 10 - F, - 20%, 35 V, 4 mm, Radial Leaded RUBYCON 4 Buy Now 50YXJ3R3M5X11 Aluminium Electrolytic Capacitor, YXJ Series, 3.3 - F, - 20%, 50 V, 5 mm, Radial RUBYCON 1 Buy Now 860020772004 Aluminium Electrolytic Capacitor, WCAP-ATG5 Series, 0.47 F, 20%, 63 V, 5 mm, Radial Leaded WURTH ELEKTRONIK 1 Buy Now 860130374004 CAP, 220UF, 16V, ALU ELEC, RADIAL WURTH ELEKTRONIK 1 Buy Now ECA1CAK330X Electrolytic Capacitor, 33 µF, 16 V, ± 20%, Radial Leaded, 2000 hours @ 85°C, Polar PANASONIC 1 Buy Now MCNP35V476M8X11.5 Electrolytic Capacitor, 47 µF, 35 V, ± 20%, Radial Leaded, 2000 hours @ 85°C, Bi-Polar [Non-Polar] MULTICOMP PRO 3 Buy Now MCNP100V105M5X11 Electrolytic Capacitor, 1 µF, 100 V, ± 20%, Radial Leaded, 2000 hours @85°C, Bi-Polar [Non-Polar] MULTICOMP PRO 1 Buy Now 16ML100MEFC6.3X7 Electrolytic Capacitor, Miniature, 100 µF, 16 V, ± 20%, Radial Leaded, 5000 hours @ 105°C, Polar RUBYCON 1 Buy Now MCUMR35V475M4X5 Aluminium Electrolytic Capacitor, MCUMR Series, 4.7 - F, - 20%, 35 V, 4 mm, Radial Leaded MULTICOMP PRO 1 Buy Now ECE-A1EKS4R7 Electrolytic Capacitor, 4.7 µF, 25 V, ± 20%, PC Pin, 1000 hours @ 85°C, Polar PANASONIC 1 Buy Now 50ML1MEFC4X5 Electrolytic Capacitor, Miniature, 1 µF, 50 V, ± 20%, Radial Leaded, 3000 hours @ 105°C, Polar RUBYCON 1 Buy Now EEUFR1E471B Electrolytic Capacitor, 470 µF, 25 V, ± 20%, Radial Leaded, 6000 hours @ 105°C, Polar PANASONIC 1 Buy Now WXHAP200 - Desoldering tool for Weller WXR3 Weller 1 Buy Now Additional Parts: TRS-80 Model 100 element14 Presents | About James | Workbench Wednesdaysre-capchoosing capacitorleaked capacitorcapacitor replacementelectrolytic capacitor