Integrated Circuits Inc. aIVR1004/2104/4208
Oct 12, 2009
5V CPU Control with COUT
1. C1 is capacitor from 0.1uF to 2.2uF depends on the kind of Vdd source and sound loudness.
E.g. If COUT is used, C1 can be 0.1uF. However, if PWM direct drive speaker is used, C1
should be at least 2.2uF
2. Rb is base resistor from 120 Ohm to 390 Ohm depends on Vdd value and transistor gain.
3. Tr is an NPN transistor with beta larger than 150, e.g. 8050D.
4. Rosc = 610K Ohm with Vdd=3.0V and support sampling rate up to 14KHz
5. For sampling rate higher than 14KHz, smaller value of Rosc should be used.
PB0 to PB2 set to internal pull-up
Addr to  are open drain output