AMC3301: May I use this device in full differential input mode?

John11513

Part Number: AMC3301

Hi,

As the datasheet, AMC3301 should be used in single ended mode: connecting negative input (INN) to floating ground (HGND). I am wondered if it is possible to operate the device input in fully differential mode as long as the input common mode range is maintained? (-0.16V to 1V)

The reason why asking this question is i am proposing customer to measure high DC voltage (+/-1kV) with this device. Considering the high resistance divider is used, a buffer has to be used in front of AMC3301 to maintain accuracy. Since the buffer is powered from single polar supply (HLDOout), to achieve +/-1000V input range the device has to be operated in fully differential mode.

Thank you,

John

over 4 years ago

0 Tom Hendrick over 4 years ago

TI__Guru**** 168605 points

Hi John,

The AMC3301 has a differential input stage, so no issues there. You just have to maintain the input common mode voltage levels noted throughout the datasheet. Also, we are still evaluating the capabilities of the AMC3301 with respect to the amount of power that can be delivered from HLDOout to external circuits. Let's take that portion of the discussion off line for now.

0 kai klaas69 over 4 years ago in reply to Tom Hendrick

Guru 140200 points

Hi Tom,

what about the input bias currents? I think a current path to HGND has to be provided?

Kai

0 John11513 over 4 years ago in reply to kai klaas69

TI__Expert 5360 points

Hi Kai,

Yes, you are right. The input differential buffer i mentioned can easily provide biasing to AMC3301 input.

Thanks,

John

Amplifiers

Amplifiers forum

AMC3301: May I use this device in full differential input mode?