diyAudio (
-   Power Supplies (
-   -   regulated power suuply for Texas TPA3100D2 evaluation board (

kp93300 30th August 2012 12:58 AM

regulated power suuply for Texas TPA3100D2 evaluation board
1 Attachment(s)
please see the attached schematic.
I want to build a 20V 6amp regulated power supply for the class d amp that has a a peak power requirement of 26 V and 4 amp.
would like to receive feedback and build suggestions .



DUG 30th August 2012 03:15 AM

I am in the process of putting together an amp using the TPA3116D2

I designed my own board for it (now I can't find my 3 free samples but they are around here somewhere)

I also wanted to use a regulated supply

I am planning to use a zener / bjt feedback type power FET regulator and did some calculations of the transformer / filter cap size I would need for a 26V 6.5A regulated supply

With a good 24VAC secondary transformer and allowing a 2V drop for the diode ( I don't have Electronic workbench installed and some assumptions are made), 10,800uF would give me 1.76V headroom for the regulator and a regulator power dissipation of 25.6W. The peak rectifier current is about 71A.

Changing the filter cap to 12,600uF would increase the headroom to 2.3V, the power dissipation to 27.3W and peak diode current to 76A.

The reason for the cap sized is that I have a large quantity of 1800uF 50V low esr caps that were pulled from some equipment destined to be scrapped

I hope to hear more of the evaluation board

Which devices are you going to use?

kp93300 30th August 2012 04:30 AM

Hi Dug,

I report my findings with the eval board here



tabarddn 2nd December 2012 08:50 AM

Battery - Why not
Hi, Why don't you guys just use a desent 24 v battery, These units have a very low power drainage and should be ideal for a SLA.

DUG 2nd December 2012 04:00 PM


Originally Posted by tabarddn (
Hi, Why don't you guys just use a desent 24 v battery, These units have a very low power drainage and should be ideal for a SLA.

I want to listen to music, not sit and watch them not consume power.


tabarddn 7th December 2012 09:40 AM

Battery supply
You should try to get off the grid in you want to listen to the best music.
Easy to set up feeding amps with 12 to 24volts for superior sound. No brown outs and you can even listen in a power cut, we all get them.:D

DUG 7th December 2012 10:56 AM

kp93300, in your first post there are some parts that I don't know why they are there.

P2, D7, D8, D9

Could you explain what they contribute in this circuit, please?

kp93300 9th December 2012 12:53 PM

Hi Dug
I didnot build the circuit in the first post .
I build a regulated power supply based on LM 338 and a pretracking regulator based on this circuit

Just one thing about music - when it hits you feel no pain

It is based on Part 4 of the blog on using the 3 pin regulator. I replace the LM 318 with the LM338. Read the part 1 to part 4 of the blog on using the 3 pin regulators.
The information are very helpful in understanding the circuit.

I am very happy with the sound which is much better than an smps laptop battery .


DUG 9th December 2012 02:29 PM

Very interesting blog but I still can't see what P2, D7, D8, D9 do.

Thanks for the link anyway...learn something every day.

rsavas 10th December 2012 05:58 PM

A regulated power supply is really not needed. I have designed a portable stereo using the TPA3100D2, it runs from a wall-wart, anything from 12V to 18-20V, works just fine. I have 4700uF/35V ecap for bulk storage and two low ESR 220uF/35V caps on each rail closer to the device, it works fine. A regulated PS is really just a waste of time, money, power. I doubt very much that you will hear any sonic difference, if you use a regulated supply. The whole idea of using a class "D" amp is for efficiency gains, you are basically throwing the efficiency gains away by using a linear regulator.
Using a battery is not a very good economical solution either!!
I have been testing my design out using a lab supply, I can not tell the difference between my lab supply and the wall-wart!!
Sorry if I am off topic here and you are requiring a lab supply to be used for testing purposes only and it is not meant to be the PS for this amp long term.


All times are GMT. The time now is 03:54 AM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2