Linear Technology DC2132A CV&CC Adj. Bench Power Supply Board

[szolusha]

Hi folks,

This is a demonstration circuit meant to show off the ability of the parts. It is not meant to be mass produced and sold by LTC.
We provide the files, schematic, etc. to you so that you can go and produce your own. BOM cost for somebody doing this might be sub $50.
We are not making money off of these boards since we put a lot of engineering time and gathering of small number of components (as well as assembly and testing).

Instead, these boards are provided as demonstration of what you can build on your own. If we set the price as low as the BOM, then some places come in and sweep up 50 boards and we run out of stock, forcing us to remanufacture small amount of boards, making it hard for those interested in producing their own to get his/her own demo.

If you want samples of this, get in touch with your local sales office. Thanks for looking at the board.
LTC parts traditionally are very high performance.
I wrote the LT Journal article on the bench supply demo to give you as much information as possible.

On the schematic, INTVcc is generated by the LT8612. It does not need an extra supply to get this rail. I am sorry if you did not catch that in the schematic.

K Szolusha

[prasimix]

It took a bit longer than expected but I had a go at testing the board.

So far it performs really nice.

Power consumption
Idle load @ 35VIN, no output connected = 17mA

PowerIn @ 35VIN, 3V3 3A Out = 35V x 470mA = 16,45W
PowerOut @ 35VIN, 3V3 3A Out  = 3,3V x 3A = 9,9W
Ploss = 16,45W - 9,9W = 6,55W
n = ~60%

Temperature LT3080 @ 25C Amb
@ 35VIN, 3V3 3A Out:
Temp 1 = 0,63V
Temp 2 = 0,65V

Load regulation (on output terminals)
@ 35VIN, 3V3 3A Out :
Vout no load = 3,30V
Vout full load = 3,28V

Noise and transient response
Noise no load: ~10mV
Noise 3A load:  ~28mV

0-3A Transient response overshoot: ~160mV
3-0A Transient response undershoot: ~316mV

Thanks DutchGert for sharing. Is it possible to provide how Vout looks like during power up and power down in CV mode with and without load, and in CC mode?

[dadler]

Sorry to bump an old thread-

I'm trying to fully understand this circuit. It seems that the LTC3632 is configured as a constant current load that can pull the output below ground--to satisfy the minimum load requirements of the LT3081s.

Is this correct? If so, is there a simpler way of doing this and still maintaining 0v output? It seems complex to introduce an entire additional switching regulator just to satisfy the minimum load.

Thanks

[parasole]

In my understanding you still need to have negative supply, regardless how do you provide it...

[dadler]

In my understanding you still need to have negative supply, regardless how do you provide it...

Thanks. I suspect you are right, I missed this part of the datasheet (which makes sense):

Regulation of the output voltage requires a minimum load current of 5mA. For true zero voltage output operation, return this 5mA load current to a negative output voltage.

I was hoping there was some way to achieve 0v output without a negative supply, but I suspect that is not possible.

[parasole]

Hi folks,

I just received DC2132A ref design PCBs, I found the design in Circuit maker and ordered them as is, good enough for lab power supply.
If anyone is interested, I have 3 spare PCB that may sell out for fabrication cost (4USD each) + shipping, if interested pls PM me...

BR//

[parasole]

PCB

[dobsonr741]

Where did you find available stock of the Linear parts?

[dobsonr741]

Where did you find available stock of the Linear parts?