TSS721ADR DataSheet
DATASHEET
TSS721ADR 描述
NOTES: 1. Stresses greater than those listed under ABSOLUTE MAXIMUM RATINGS may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability. 2. VCC terminals. 3. Input terminals. 4. Outputs and I/O terminals.
TSS721ADR 特点
Function Regulated output voltage of 2.7 V for biasing a DTMF generator activated by MUTE. The receive amplifier input. The receiving amplification is regulated of an a.g.c. Positive supply voltage input to the device. This input should be connected to the positive output of the polarity guard. The current through this pin is modulated by the transmit signal. An external resistor (2 W) is required from this pin to GND to control the dc input impedance of the circuit. It has a nominal value of 56 W for low voltage operation. Values up to 100 W may be used to increase the available transmit output voltage swing at the expense of low- voltage operation. This internal voltage bias line must be connected to VL via an external resistor, RB, which dominates the ac input imped- ance of the circuit and should be 620 Ω for an 600 W input impedance or 910 Ω for a 900 Ω input impedance. The range of transmit and receive gain variations between short and long loops may be adjusted by connecting a resistor REX1 from this pin to Pin 3 (GND). This pin can be left open to set a.g.c. out of action.
TSS721ADR 应用
Technical/Catalog InformationTSS721ADRVendorTexas InstrumentsCategoryUndefined Category Lead Free StatusLead Free RoHS StatusRoHS Compliant Other Names TSS721ADR
TSS721ADR