| 摘要 |
<p>PURPOSE:To control an analog IC by a logic signal. CONSTITUTION:A main signal processing IC 2 reads out corresponding digital data from an internal mode register 2a by a signal from a bus line 1. Read out data is converted into a corresponding voltage signal by a D/A converter 2c for external control, and is supplied to a microphone amplifier IC 3 and a speaker amplifier IC 4. Therefore, the amplification factors of those microphone amplifier IC 3 and speaker amplifier IC 4 can be controlled by a digital signal from the bus line 1.</p> |
