SNC204

Direct Drive Speech Controller

5.8. DAC & PWM

SNC204 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 SNC204. 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: 1.1

June 8, 2005

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