http://focus.ti.com/lit/ds/symlink/tlv2211.pdfsingle lincmos(tm) rail-to-rail upower operational amplifier
上面标记就是vacc
the tlv2211 is a single low-voltage operational
amplifier available in the sot-23 package. it
consumes only 11 μa (typ) of supply current and
is ideal for battery-power applications. looking at
figure 1, the tlv2211 has a 3-v noise level of
22 nv/√hz at 1khz; 5 times lower than competitive
sot-23 micropower solutions. the device
exhibits rail-to-rail output performance for increased
dynamic range in single- or split-supply
applications. the tlv2211 is fully characterized
at 3 v and 5 v and is optimized for low-voltage
applications.
the tlv2211, exhibiting high input impedance
and low noise, is excellent for small-signal
conditioning for high-impedance sources, such as
piezoelectric transducers. because of the micropower
dissipation levels combined with 3-v
operation, these devices work well in hand-held
monitoring and remote-sensing applications. in
addition, the rail-to-rail output feature with single
or split supplies makes this family a great choice
when interfacing with analog-to-digital converters
(adcs).
