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SP312A

RS-232 Line Driver/Receiver

The SP312A is a rs-232 line driver/receiver from MaxLinear. View the full SP312A datasheet below including key specifications, pinout, electrical characteristics, absolute maximum ratings.

SP312A shares its datasheet with SP3485, whose page lists every part number it covers.

Official SP312A datasheet (PDF) — the source this page was extracted from.

Manufacturer

MaxLinear

SP312A Key Specifications

ParameterValue
InterfaceRS-232 / ITU V.28
Max Data Rate120Kbps under load (240Kbps typ)
ESD Protection±2kV (Human Body Model)
Number Of Drivers2
Number Of Receivers2
Receiver Hysteresis0.5V typ
Output Voltage Swing±5V min, ±6V typ
Supply Voltage (VCC)+5V ± 10%
Charge Pump Capacitors0.1µF to 1µF
Shutdown Supply Current1µA typ, 10µA max
Supply Current (Loaded)25mA typ
Receiver Input Threshold0.8V to 2.4V
Supply Current (No Load)10mA typ, 15mA max
Operating Temperature Range0°C to +70°C (C); -40°C to +85°C (E)
Receiver Input Voltage Range±30V

SP312A Overview

Part: SP232A/233A/310A/312A — Sipex

Type: Enhanced RS-232 Line Drivers/Receivers

Description: A family of line driver and receiver pairs operating from a single +5V supply, meeting RS-232F and ITU V.28 specifications with a 120Kbps data rate under load and low power CMOS design.

Operating Conditions:

  • Supply voltage: +4.5V to +5.5V
  • Operating temperature: 0°C to +85°C
  • Charge pump capacitors: 0.1 μF to 1 μF
  • Max data rate: 120 Kbps (under load)

Absolute Maximum Ratings:

  • Max supply voltage (Vcc): +6V
  • Max input voltage (RIN): ±30V
  • Max output short circuit duration (TOUT): Continuous

Key Specs:

  • TTL Logic Threshold LOW: 0.8 V (max)
  • TTL Logic Threshold HIGH: 2.0 V (min)
  • RS-232 Output Voltage Swing: ±5 V (min) (All transmitter outputs loaded with 3kΩ to Ground)
  • Maximum Data Rate: 120 Kbps (min) (C L = 2500pF, R L = 3kΩ)
  • RS-232 Input Voltage Range: -30 V to +30 V
  • RS-232 Input Resistance: 3 kΩ (min) to 7 kΩ (max) (T A = +25°C, -15V ≤ V IN ≤ +15V)
  • Driver Propagation Delay: 1.5 μs (typ), 3.0 μs (max) (TTL to RS-232; C L = 50pF)
  • V CC Power Supply Current (SP232A): 3 mA (typ), 5 mA (max) (No load, T A = +25°C; V CC = 5V)
  • Shutdown Supply Current (SP310A, SP312A): 1 μA (typ), 10 μA (max) (V CC = 5V, T A = +25°C)

Features:

  • Operates from Single +5V Power Supply
  • Meets All RS-232F and ITU V.28 Specifications
  • Operates with 0.1 μF to 1 μF Capacitors
  • High Data Rate - 120Kbps Under Load
  • Low Power CMOS - 3mA Operation (SP232A)
  • No External Capacitors Required (SP233A)
  • Low Power Shutdown (SP310A, SP312A)
  • Enhanced ESD Protection (2kV Human Body Model)

Package:

  • 16-pin NSOIC
  • 16-pin PDIP
  • 16-pin WSOIC
  • 18-pin WSOIC
  • 20-pin PDIP
  • 20-pin WSOIC

SP312A Features

  • ■ Operates from Single +5V Power Supply
  • ■ Meets All RS-232F and ITU V.28 Specifications
  • ■ Operates with 0.1 μ F to 1 μ F Capacitors
  • ■ High Data Rate - 120Kbps Under Load
  • ■ Low Power CMOS - 3mA Operation (SP232A)
  • ■ No External Capacitors Required (SP233A)
  • ■ Low Power Shutdown (SP310A,SP312A)
  • ■ Enhanced ESD Protection (2kV Human Body Model)

Now Available in Lead Free Packaging

DESCRIPTION

The SP232A/233A/310A/312A devices are a family of line driver and receiver pairs that meet the specifications of RS-232 and V.28 serial protocols. These devices are pin-to-pin compatible with popular industry standards. As with the initial versions, the SP232A/233A/310A/312A devices feature at least 120Kbps data rate under load, 0.1 μ F charge pump capacitors, and overall ruggedness for commercial applications. This family also features Sipex's BiCMOS design allowing low power operation without sacrificing performance. The series is available in plastic DIP and SOIC packages operating over the commercial and industrial temperature ranges.

SP312A Pin Configuration

SP312A – 18-Pin PDIP/WSOIC

Pin NumberPin NameTypeDescription
1ENIEnable (Tri-state control for receiver outputs; SP312A only)
2T1INITransmitter 1 Input
3T1OUTOTransmitter 1 Output (RS-232)
4R1INIReceiver 1 Input (RS-232)
5R1OUTOReceiver 1 Output (TTL)
6T2INITransmitter 2 Input
7T2OUTOTransmitter 2 Output (RS-232)
8R2INIReceiver 2 Input (RS-232)
9R2OUTOReceiver 2 Output (TTL)
10C1-PCharge Pump Capacitor 1 Negative
11C1+PCharge Pump Capacitor 1 Positive
12V-PNegative Supply (generated by charge pump)
13C2+PCharge Pump Capacitor 2 Positive
14C2-PCharge Pump Capacitor 2 Negative
15GNDPGround
16VCCPPositive Supply (+5V)
17V+PPositive Supply (generated by charge pump)
18SDIShutdown Control (SP312A only; active low)

Notes

  • SP312A specifics: Pin 1 (EN) and Pin 18 (SD) are unique to the SP312A variant. EN controls tri-state of receiver outputs; SD controls shutdown mode and transmitter tri-state.
  • Wake-up feature: SP312A supports selective receiver activation during shutdown (see Truth Table 1 in datasheet).
  • Charge pump capacitors: C1+/C1- (pins 11/10) and C2+/C2- (pins 13/14) require external 0.1–1 μF capacitors.
  • Pin compatibility: SP312A is pin-compatible with SP310A (which has ON/OFF on pin 18 instead of separate SD/EN).
  • Package variants: SP312ACP (18-pin PDIP) and SP312ACT/SP312AET (18-pin WSOIC) share this pinout.

SP312A Electrical Characteristics

V CC =+5V ± 10%; 0.1 μ F charge pump capacitors; T MIN to T MAX unless otherwise noted.

PARAMETERSMIN.TYP.MAX.UNITSCONDITIONS
TTL INPUT
Logic Threshold LOW HIGH2.00.8Volts VoltsT IN ; EN, SD T IN ; EN, SD T IN = ZeroV
Logic Pull-Up Current TTL OUTPUT TTL/CMOS Output Voltage, Low15200μ A
3.50.4Volts VoltsI OUT = 3.2mA; Vcc = +5V I OUT = -1.0mA
Voltage, High Leakage Current; T A = +25 °0.05± 10μ AEN= V CC , ZeroV ) V OUT ) V CC SP310A and SP312A only
RS-232 OUTPUT
Output Voltage Swing± 5± 6VoltsAll transmitter outputs loaded with 3k 1 to Ground
Output Resistance Output Short Circuit Current300± 18Ohms mAV CC = ZeroV; V OUT = ± 2V Infinite duration
Maximum Data Rate120240KbpsC L = 2500pF, R L = 3k 1
RS-232 INPUT
Voltage Range-30+30Volts
Voltage Threshold1.2VoltsV = 5V, T = +25 ° C
LOW HIGH0.81.72.4VoltsCC A V = 5V, T = +25 ° C
Hysteresis0.20.51.0VoltsCC A V = 5V, T = +25 ° C
CC A
Resistance357k 1T A = +25 ° C, -15V ) V IN ) +15V
DYNAMIC CHARACTERISTICSDYNAMIC CHARACTERISTICS
Driver Propagation Delay1.53.0μ sTTL to RS-232; C L = 50pF
Receiver Propagation Delay0.11.0μ sRS-232 to TTL
Instantaneous Slew Rate30V/ μ sC L = 10pF, R L = 3-7k 1 ; T =+25 ° C
Transition Region Slew Rate10V/ μ sA C L = 2500pF, R L = 3k 1 ; measured from +3V to -3V or -3V to +3V
Output Enable Time400nsSP310A and SP312A only
Output Disable Time250nsSP310A and SP312A only
POWER REQUIREMENTS
V CC Power Supply Current SP232A35mANo load, T A = +25 ° C;V CC = 5V
SP233A, SP310A, SP312A1015mANo load, T A = +25 ° C;V CC = 5V
V CC Supply Current,Loaded SP232A15mAAll transmitters R L = 3k 1 ;
SP233A, SP310A, SP312A25mAT A = +25 ° C All transmitters R L = 3k 1 ; T = +25 ° C
Shutdown Supply Current SP310A,SP312A110μ AA V CC = 5V, T A = +25 ° C
  • N.C. for SP310E_A, EN for SP312E_A

SP312A Absolute Maximum Ratings

This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operation sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability.

V

cc

................................................................................................................................................................. +6V

V +

.................................................................................................................... (Vcc-0.3V) to +11.0V

V -

............................................................................................................................................................ -11.0V

Input Voltages

T

IN

......................................................................................................................... -0.3 to (Vcc +0.3V)

RIN

............................................................................................................................................................

±

30V

Output VoltagesOutput Voltages
T OUT.................................................................................................... (V+, +0.3V) to (V-, -0.3V) -0.3V to (Vcc +0.3V)
R OUT ................................................................................................................ Short Circuit DurationContinuous
T OUT ......................................................................................................................................... Plastic DIP .......................................................................... (derate 7mW/ ° C above +70 ° C)375mW
Small Outline ...................................................................... (derate 7mW/ ° C above +70 ° C)375mW

Variants on the same datasheet

These parts have exact links to the same datasheet. They are candidates to compare, not verified drop-in replacements; check package, pinout and electrical limits.

Part NumberManufacturerPackage
SP232AMaxLinear—
SP233AMaxLinear—
SP310AMaxLinear—

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All Interface ICs datasheetsAll MaxLinear datasheets (43)

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