LM706A0: LM706A0 EVM verify

Brian Chan

Expert 6440 points

Part Number: LM706A0

Tool/software:

Hi Team

could you suggest how to reduce load transient to +- 5% level?

below is customer side result

they also find double pulse when heavy load.

all test board is on EVM and there is no change on any component

BRs

Brian

11 days ago

0 Ben C 11 days ago

TI__Guru 56345 points

Hi Brian,

Can you provide the input voltage?

Ben

0 Brian Chan 11 days ago in reply to Ben C

TI__Expert 6440 points

Hi Ben C

All test was implement on EVM

So every setting just follow EVM default RC value. just need to refer EVM SCH

BRs

Brian

0 Ben C 11 days ago in reply to Brian Chan

TI__Guru 56345 points

Hi Brian,

The compensation network needs to modification to increase the bandwidth of the loop. See attached quickstart calculator for the new compensation network BOM.

LM706A0_quickstart_calculator_A1_EVM.xlsm

Ben

0 Brian Chan 11 days ago in reply to Ben C

TI__Expert 6440 points

Hi Ben

really appreciate. your great support here.

may I know which value should I follow?

left one calculated one? or right one which you input.

BRs

Brian

0 Ben C 11 days ago in reply to Brian Chan

TI__Guru 56345 points

Hi Brian,

Use the values on the right in the yellow box. Thanks for your comment.. :-)

Ben

0 Brian Chan 3 days ago in reply to Ben C

TI__Expert 6440 points

Hi Ben

follow the calculator result.

we find the transient behavior improve.

left part : before compensation right part: after compensation

but do we have any chance to get lower transient <5% under 4-10A transient of 3.3V output?

could I also loop in you join the discussion with customer side?

BRs

Brian

0 David Baba 3 days ago in reply to Brian Chan

TI__Mastermind 39980 points

Hello Brian,

Looks like you are close to meeting specification.

Two options.

1. increase output capacitance and recompensate.

2. increase BW further, try: RCOMP=10k, CCOMP=10nF and CHF= 10pF. you may be able to reduce Rcomp a little and tune to just meet spec...

If you need a call with customer suggest reaching out to our India apps support for local time zone support.

Taru Kapoor is the AE supporting this device in our India design center. Thanks.

David.

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LM706A0: LM706A0 EVM verify