For a battery-powered and low-ripple reference the problem is to design the negative rail of the power supply (for obtaining the -100mV signal).
In my experience the two best alternatives are:
1) a virtual ground buffered at 1/2 Vcc (Vcc= +Vcc; GND = -Vcc; 1/2Vcc = NEW (virtual) GROUND. There are a lot of IC for doing this or you can do it yourself.
2) a negative rail generator (voltage pump or inductive) some MURATA IC can generate -5Vcc from +5Vcc with 50-100 mA max load and low ripple if associated with good inductors/capacitors.
If you can use a power supply the project is much simple (transformer) but the MAINS noise (ripple) may be a serious problem in relationship with the precision of your application.
PA.Posted on: November 27, 2014, 07:42:02 19:42 - Automerged
You could use also digital potentiometers for driving voltage references as in the following datasheet:http://www.analog.com/static/imported-files/data_sheets/AD5263.pdf