Vcc=26 V
Icc max=1.8 mA
Activation voltage 12.2...13 V
Sustaining voltage 8.0...8.8 V
Internal Zener diodes to protect against over voltages High noise immunity due to built-in voltage-current

hysteresis
Ringer impedance adjustable with external components Output F1=2100...2550 Hz

F2=1500...1850 Hz