Part Number: TLV9062
Hi TI Experts,
I'm using the TLV9062 to build a difference amplifier with a designed gain of 5.1 V/V.
Setup:
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V+: 5V
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V-: GND (Single Supply)
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Topology: Standard 4-resistor difference amplifier.
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Input Signal: 1kHz Sine wave.
Issue Description:
During testing, I noticed that the gain spikes significantly when the input signal approaches the negative rail (GND).
Measurement Screenshot Observation:
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CH4 (Green): Input signal from function generator.
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CH1 (Blue): Output of the TLV9062.
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Math Trace (Dark Green): Calculated Gain (CH1 / CH4).
As shown in the attached waveform (screenshot attached), at the valley of the sine wave (approx 40mV input), the measured gain jumps to around 9 V/V, even though the design target is 5.1 V/V.
Question:
I know TLV9062 is a RRIO device, but is there a specific mechanism causing this gain increase so close to the GND rail?
Is this related to:
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Transconductance (Gm) degradation near the rail?
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Common-Mode Voltage limitations or phase reversal?
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Output stage saturation causing loop gain collapse?
Any insights into the internal behavior causing this specific "gain increase" near the negative rail would be greatly appreciated.
Thanks!
