User Manual

DM15/25 Integrator’s Manual 24 OF 38
6 Recommended Circuitry
Abbreviations:
• VCC Represents the logic supply voltage used by the application.
• VREF Represents the logic supply voltage used by the phone module.
Component proposals:
• Transistors not showing a base resistor should be interpreted as a BRT (Built in Resistor Transistor) i.e.
Toshiba RN1308.
• The inverting buffers should preferably be Schmitt-Triggered, i.e. Toshiba TC7S14 or similar.
6.1 Status
The status group contains four signals, one output signal from the application and three input signals to the application.
Phone ModuleApplication
12, MODULE_PWR_EN_B
0 = Phone Module Power OFF
1 = Phone Module Power ON
24, RINGER
VCC