SNC11A

One Channel Direct Drive Speech Controller

5.7. DAC & PWM

SNC11A is an advanced chip to be designed having two optimal methods to play

out the voices. One is DAC and the other is PWM. Upon user’s applications, user

can select either DAC or PWM in his design. Please be aware that only one

method can be activated at a time.

DAC: A 7-bit current type digital-to-analog converter is built-in SNC11A. The

relationship between input digital data and output analog current signal is listed

in the following table. Also, the recommended application circuit is illustrated as

follows.

Input data

Typical value of output current (mA)

0

0

1

3/127

…

N

n*(3/127)

…

127

3

VCC

BUO1/VO

1K

DAC output

Ver: 1.3

June 8, 2005

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