I have designed a circuit with 5V single-supply op amps, but since the inputs to the circuit are AC, I need a biasing voltage to replace the ground node on the equivalent dual supply circuit. Without getting into unnecessary circuit details, this biasing voltage may need to sink or source up to 10 mA.
The circuit amplifies signals of around 2 MHz, and originally I had used a wide bandwidth voltage regulator (TI TPS71701) to generate this biasing voltage, but I found out the hard way that this regulator is unable to sink current.
I've also tried using another, non-wide-bandwidth regulator (Diodes Inc. AP2202K), which did appear to work, but its datasheet makes no mention of being able to sink current, so I don't intend on relying on an undocumented feature.
Also I've tried using a low speed (1 MHz GBW) op amp (TI LMV342) configured in unity gain buffer topology. Although it does appear to work in practice, SPICE simulations indicate that there should be large (100 mV+) output voltage swings when sourcing/sinking a few mA of current at 2 MHz, which is unacceptable in this circuit. These swings disappear when frequency is reduced to 2 kHz. Hence I'm a little hesitant to put this into mass production.
I'm looking for suggestions of other low-cost circuits capable of generating a 2 V reference from a 3 V or 5 V supply, and which have no problem sourcing and sinking currents up to 10 mA at 2 MHz with little loss of regulation.
EDIT: I tried adding a load resistor to the output of the TPS71701 regulator, such that the amplifier circuit is able to sink current through this resistor. This did work, but now I have a constant 10 mA load (and this is a battery powered device). Actually, when in use, this product draws on the order of 1 A, so 10 mA might not be so bad, but still, I'd feel better with a circuit without a vampire current draw.