概觀
The IS31AP4912 is a Class-AB stereo headphone
inverting amplifier with charge pump controller capable
of delivering 30mW into a 32Ω load with less than
0.1% THD+N. The integrated charge pump generates
a negative reference voltage to bias the outputs about
ground. This eliminates the need for output DC-
blocking capacitors resulting in a lower component
count and cost. The gain of the amplifier is adjusted
via external resistors.
The IS31AP4912 integrates click-and-pop
suppression circuitry to eliminate speaker noise which
would occur during power ON/OFF transitions. It also
integrates a thermal protection circuit to shutdown the
amplifier if it gets too hot. Setting the SDB pin to a low
state will cause the IS31AP4991 to enter a low-power
shutdown mode with a quiescent current of less than
1µA.
The IS31AP4912 is ideal for small portable electronics
where size, battery life and cost are critical design
parameters. IS31AP4912 is available in a space
saving UTQFN-12 (2mm × 2mm) package. It operates
from 2.7V to 5.5V over the temperature range of -40°C
to +85°C.