MC33121FN ,LOW VOLTAGE SUBSCRIBER LOOP INTERFACE CIRCUITELECTRICAL CHARACTERISTICS(V = – 24 V, V = + 5.0 V, unless otherwise noted. V = V = V = 0 V, T = 25 ..
MC33121P ,LOW VOLTAGE SUBSCRIBER LOOP INTERFACE CIRCUITMAXIMUM RATINGSCharacteristic Symbol Value UnitSupply Voltage Vdc(with respect to V ) V – 60, + 0.5 ..
MC33128 ,POWER MANAGEMENT CONTROLLERELECTRICAL CHARACTERISTICS (V = 4.5 V, C = 33 μF with ESR ≤ 1.6 Ω, C = 4.7 μF with ESR ≤ 4.5 Ω, I = ..
MC33128D ,POWER MANAGEMENT CONTROLLERELECTRICAL CHARACTERISTICS (V = 4.5 V, C = 33 μF with ESR ≤ 1.6 Ω, C = 4.7 μF with ESR ≤ 4.5 Ω, I = ..
MC33128D ,POWER MANAGEMENT CONTROLLERELECTRICAL CHARACTERISTICS (V = 4.5 V, C = 33 μF with ESR ≤ 1.6 Ω, C = 4.7 μF with ESR ≤ 4.5 Ω, I = ..
MC33129D ,HIGH PERFORMANCE CURRENT MODE CONTROLLERSOrder this document by MC34129/D ** * * **HIGH PERFORMANCEThe MC34129/MC33129 are high performance ..
MC74HC175 ,Quad D Flip-Flop with Common Clock and ResetELECTRICAL CHARACTERISTICS (Voltages Referenced to GND)ÎGuaranteed LimitÎÎÎÎÎÎV V – 55 toC CC CÎÎÎS ..
MC74HC175 ,Quad D Flip-Flop with Common Clock and ResetMaximum Ratings are those values beyond which damage to the device may occur.ÎÎÎÎÎFunctional operat ..
MC74HC175A ,Quad D-type Flip-Flop with Common Clock and Reset3MC74HC175ATIMING REQUIREMENTS (Input t = t = 6 ns)r fÎÎÎÎÎÎ Guaranteed LimitÎÎÎÎ VÎÎÎÎÎÎ – 55 toÎÎ ..
MC74HC175ADR2 ,Quad D-type Flip-Flop with Common Clock and ResetMAXIMUM RATINGS*ÎÎÎÎÎÎ Symbol ParameterÎÎÎÎÎ ValueÎÎÎ UnitThis device contains protectioncircuitry ..
MC74HC175AFEL ,Quad D-type Flip-Flop with Common Clock and ResetELECTRICAL CHARACTERISTICS (C = 50 pF, Input t = t = 6 ns)L r fÎÎGuaranteed LimitÎÎÎÎÎÎV– 55 toCCVS ..
MC74HC175AFL1 ,Quad D Flip-Flop with Common Clock and ResetELECTRICAL CHARACTERISTICS (C = 50 pF, Input t = t = 6 ns)L r fÎÎGuaranteed LimitÎÎÎÎÎÎV– 55 toCCVS ..
MC33121FN-MC33121P
LOW VOLTAGE SUBSCRIBER LOOP INTERFACE CIRCUIT
- -
Thin Film Silicon Monolithic Integrated CircuitThe 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 kΩ Leakage Single/Double Fault Indication With Shutdown for Thermal Protection Critical Sense Resistors Included Internally Standard Power Supplies: – 21.6 V to – 42 V, and + 5.0 V, ± 10% On–Hook Transmission Power Down Input (TTL and CMOS Compatible) Operating Ambient Temperature: – 40°C to + 85°C Available in a 20 Pin DIP and 28 Pin PLCC Package
SIMPLIFIED BLOCK DIAGRAMVCC
VEE
(BATTERY)
TIP
RINGVDD (+5.0 V)
VDG
(DIG. GND)
PDI/ST2
ST1
VAG
(ANA. GND)
RXI
TXO
RFO
VQB
Order this document
by MC33121/D-
SEMICONDUCTOR TECHNICAL DATA
ORDERING INFORMATION
