SNC558
Two Channel Direct Drive Speech Controller
Input data
0
1
…
N
…
127
Typical value of output current (mA)
0
3/127
n*(3/127)
3
VCC
BUO1/VO
1K
DAC output
PWM: A PWM (pulse width modulation) circuit is built-in SNC558. PWM can
convert input digital data into pulse trains with suitable different pulse width. The
maximum resolution of PWM is 7 bits. Two huge output stage circuits are
designed in SNC558. With this advanced circuit, the chip is capable of driving
speaker directly without external transistors. The recommended application
circuit is illustrated as follows.
BUO1/VO
BUO2
Ver: 1.2
PWM Output
6
November 26, 2002