器件名称: MC33121FN
功能描述: LOW VOLTAGE SUBSCRIBER LOOP INTERFACE CIRCUIT
文件大小: 570.99KB 共32页
简 介:MOTOROLA
SEMICONDUCTOR TECHNICAL DATA
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MC33121 Low Voltage Subscriber Loop Interface Circuit (SLIC) Thin Film Silicon Monolithic Integrated Circuit
The MC33121 is designed to provide the interface between the 4–wire side of a central office, or PBX, and the 2–wire subscriber line. Interface functions include battery feed, proper loop termination AC impedance, hookswitch detection, adjustable transmit, receive, and transhybrid gains, and single/ double fault indication. Additionally, the MC33121 provides a minimum of 58 dB of longitudinal balance (4–wire and 2–wire). The transmit and receive signals are referenced to analog ground, while digital signals are referenced to digital ground, easing the interface to codecs, filters, etc. The 2 status outputs (hookswitch and faults) and the Power Down Input are TTL/CMOS compatible. The Power Down Input permits local shutdown of the circuit. Internal drivers allow the external loop current pass transistors to be standard bipolar transistors (non–Darlington). The MC33121 is available in a 20 pin DIP and a 28 pin PLCC surface mount package. 58 dB Longitudinal Balance Guaranteed; 4–wire and 2–wire Transmit, Receive, and Transhybrid Gains Externally Adjustable Return Loss Externally Adjustable Proper Hookswitch Detection With 30 k Leakage Single/Double Fault Indication With Shutdown for Thermal Protection Critical Sense Resistors Included Internally Standard Power Supplies: – 21.6 V to – 42 V,……