NTE1690 Datasheet | NTE Electronics

Description : The NTE1690 is a low threshold voltage, field- implanted, metal gate CMOS integrated circuit in a 16- Lead DIP type package. This device interfaces directly to a standard telephone keypad and generates all dual tone multi- frequency pairs required in tone dialing systems. The tone synthesizers are locked to an on- chip reference oscillator using an inexpensive 3.579545MHz crystal for high tone accuracy. The crystal and an output load resistor are the only external ponents required for tone generation. A MUTE OUT logic signal, which changes state when any key is depressed is also provided. Features : D 3V to 10V Operation When Generating Tones D 2V Operation of Keyscan and MUTE Logic D Static Sensing of Key Closures or Logic Inputs D On- Chip 3.579545MHz Crystal- Controlled Oscillator D Output Amplitudes Proportional to Supply Voltage D High Group Pre- Emphasis D Low Harmonic Distortion D Open Emitter- Follower Low- Impedance Output D SINGLE TONE INHIBIT Pin Absolute Maximum Ratings: Supply Voltage (VDD - VSS) - - - - - - - - - - - . . . 15V Maximum Voltage at Any Pin - - - - - - - . . . . VDD+0.3V to VSS- 0.3V Power Dissipation, PD - - - - - - - - - - - . . . 500m W Operating Temperature Range, Topr - - - - - - - - . - 30° to +60°C Storage Temperature Range, Tstg - - - - - - - - . . - 55° to +150°C Electrical Characteristics: (- 30°C < TA < +60°C, 3V < VDD < 10V unless otherwise specified) Parameter Minimum Supply Voltage for Keysense and MUTE Logic Functions Operating Current, Idle Operating Current, Generating Tones RL = 10kΩ VO = 5V Test Conditions Min - - - Typ - 20 2 Max 2 - - Unit V µA m A Electrical...