Vishay Synchronous Buck Regulator EV Board - Review

Table of contents

RoadTest: Vishay Synchronous Buck Regulator EV Board

Author: rsc

Creation date:

Evaluation Type: Power Supplies

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?: LM78XX, LM350 with a MOSFET driver and some fault circuits or COMPAQ laptop vehicle power supply adapter, driving a MW SD-15B-05 DC to DC converter, for 5V 3A output

What were the biggest problems encountered?: No problems encountered.

Detailed Review:

I was looking for a good power supply to use a Raspberry Pi in my truck, and this road test came along just in time.

Unboxing:

 

The VISHAY Power IC Evaluation Board SIC461EVB-A came in a nice foam lined box, and included two extra inductors, 3.3uh and 10uh.

My board has a 5.6uh installed and the output voltage was set to 5VDC.

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Enclosure:

Because I want to use this in my truck, I made a simple 3D printed enclosure.

One con for this board is a lack of mounting holes.

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Initial Testing:

I used a variable power supply on the input lines to check the output voltage.

The advertised input voltage from the specification data sheet:

>> Single supply operation from 4.5 V to 60 V input voltage for SiC461 and SiC462, and 55 V for SiC471 and SiC472

My board shuts down below 9.5VDC on the input.  I haven't tried to change any of the factory settings for now.

Since I'm planning to use the board in an automotive application, 9.5V-16 should be fine.

I wanted to see how the board started up and shut down, so I connected an oscilloscope to the output and a 4S 14.8VDC LiPo on the input.

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I set the trigger for rising edge capture and plugged in the LiPo battery.

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The rise time with no load was 3.95ms, with a RPi 4 as a load, the rise time was slightly longer.

(Note the scale on the above graph is 5ms/div and 1ms/div below)

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I measured about +-20mv ripple on the DC. The background noise on the scope is +-850uv with the probe grounded.

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The fall time with no load was very long >10s.  The fall time with the RPi 4 connected dropped quickly to about 2.5VDC, then fell slowly to 0V.

Vehicle Test:

The next test was to plug the microBUCK board into my truck cigarette lighter port and see how it handles ignition noise.

Here's the setup:

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The Keyon ACC test looked similar to the battery test on the bench.

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Key off voltage drop was also similar to battery test

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The Keyon crank and start test had two starts with a dropout, but it followed the same patterns as before.

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The Raspberry Pi didn't seem to mind the double start, although it could be a problem depending on where in the boot cycle it is when the power drops out.

I will need to investigate this further, maybe add a power switch or a larger output cap for vehicle starting.

This is an ongoing project, and I'm still building up the final system, but I believe the VISHAY microBUCK will work well for this application.

My original solution was a COMPAQ laptop vehicle power supply adapter, driving a MW SD-15B-05 DC to DC converter, for 5V 3A output.

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Summary:

The VISHAY Power IC Evaluation Board SIC461EVB-A seems to work as advertised, although I haven't tried to modify the board for different voltages

or otherwise change the factory configuration since it fits my application as received.

I may only need 3-4A depending on how I set up my IR LED array for the night vision security camera feature.

I will update this road test as I build more of the system, so far the board works well.  I'll do some thermal tests and efficiency also.

Thanks VISHAY and Element14 for letting me evaluate this board.

Anonymous