LT1080CJ - 5V RS232 Dual Driver/Receiver, 18-CERDIP | Linear Technology
N.º da peça: LT1080CJ ✓ Ativo| Qtd. | Preço unitário | Total |
|---|---|---|
| 1 | $15.05 | $15,05 |
| 10 | $13.8 | $138,00 |
| 100 | $12.2 | $1.220,00 |
| 500 | $10.75 | $5.375,00 |
| 1.000 | $9.4 | $9.400,00 |
LT1080CJ Visão geral
An RS232 transceiver is a type of line driver/receiver IC that converts TTL/CMOS logic levels (0V to 5V) to RS232 voltage levels (typically ±5V to ±15V) for serial data communication, or vice versa. RS232 transceivers sit hierarchically under interface ICs, then under integrated circuits, in the broader system taxonomy of communication and bus conversion components. They remain widely used in industrial serial ports, point-of-sale terminals, and legacy computer interfaces.
Key features include superior CMOS drive capability versus older bipolar parts, three-state driver outputs that go high-impedance when shut down, ±30V overvoltage tolerance on driver outputs, and absolute latchup immunity under all conditions. The integrated charge pump uses small 1µF external capacitors, reducing board area compared to legacy RS232 designs that required 10µF or larger capacitors.
The architecture uses an on-chip DC-DC charge pump to generate the ±10V RS232 supplies from a single 5V rail, eliminating the need for a negative supply. The shutdown pin puts the device in a low-current state with driver outputs tri-stated, allowing the part to share a serial bus with other drivers or to power down for energy-sensitive applications.
Typical applications include industrial serial communication ports, point-of-sale (POS) terminals, legacy computer peripheral interfaces, embedded system debug consoles, and battery-powered handheld instruments that require a single-supply RS232 link. The shutdown feature is particularly useful in portable and battery-powered designs where quiescent current matters.
When designing with the LT1080CJ, ensure the four charge-pump capacitors (typically 1µF) are placed as close to the IC pins as possible, and that the shutdown pin is properly driven (logic low for active, logic high for shutdown). Note that the CERDIP package is through-hole only - for surface-mount designs, the LT1080CN#PBF (PDIP-18) or LT1080CSW#PBF (SO-18) variants should be considered instead.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes for the LT1080CJ not found in the manufacturer datasheet alone, with cross-references to compatible 18-pin DIP-family RS232 transceivers.
Alternativas drop-in para LT1080CJ — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
Ferramenta de comparação rápida — selecione peças alternativas para comparação lado a lado:
LT1080CN#PBF
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
LT1080CSW#PBF
✅ Drop-In ⚠️ Especificações não verificadas📋 Alternativa de referência (fora do catálogo)
LT1180CJ
✅ Drop-In ⚠️ Especificações não verificadas📋 Alternativa de referência (fora do catálogo)
LT1080IN#PBF
✅ Drop-In ⚠️ Especificações não verificadas📋 Alternativa de referência (fora do catálogo)
ADM232AANZ
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MAX232CPE+
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MAX232IN
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
LT1080CJ Especificações
| Função | Transceiver |
| Protocol | RS232 |
| Number of Drivers/Receivers | 2/2 |
| Taxa de dados | 120 kBaud (minimum, superior to CMOS) |
| Tensão de alimentação | 5 V (single supply) |
| Output Voltage Swing (RS232) | ±5 V to ±15 V typical (from charge pump) |
| Driver Output Overvoltage Tolerance | ±30 V (without damage) |
| Receiver Input Range | ±30 V (typical) |
| Charge Pump Capacitors | 4 x 1 µF (external) |
| Shutdown Mode | Yes (drivers go to high-impedance) |
| Latchup Immunity | Absolute (no latchup under any condition) |
| Faixa de temperatura de operação | 0°C to +70°C (commercial grade) |
| Encapsulamento | 18-pin CERDIP (J) - through-hole |
| Tipo de montagem | Through-Hole |
| Number of Terminals | 18 |
| Terminal Form | Through-Hole |
| Package Code | DIP |
Configuração de pinos do LT1080CJ
| Pino 1 | C1+ — Charge pump capacitor 1 positive terminal |
| Pino 2 | V+ — Positive charge pump output (+10V) |
| Pino 3 | C1- — Charge pump capacitor 1 negative terminal |
| Pino 4 | C2+ — Charge pump capacitor 2 positive terminal |
| Pino 5 | C2- — Charge pump capacitor 2 negative terminal |
| Pino 6 | V- — Negative charge pump output (-10V) |
| Pino 7 | SD — Shutdown input (active high, tri-states drivers) |
| Pino 8 | GND — Ground |
| Pino 9 | DOUT1 — Driver 1 output (RS232 level) |
| Pino 10 | DIN1 — Receiver 1 input (RS232 level) |
| Pino 11 | ROUT1 — Receiver 1 output (TTL/CMOS level) |
| Pino 12 | DOUT2 — Driver 2 output (RS232 level) |
| Pino 13 | DIN2 — Receiver 2 input (RS232 level) |
| Pino 14 | ROUT2 — Receiver 2 output (TTL/CMOS level) |
| Pino 15 | VCC — +5V supply input |
| Pino 16 | NC — Not connected (per datasheet) |
| Pino 17 | NC — Not connected (per datasheet) |
| Pino 18 | GND — Ground |
Aplicações típicas
LT1080CJ é adequado para 6 aplicaçãos: Industrial RS232 Serial Port, Point-of-Sale (POS) Terminal, Embedded System Debug Console, Battery-Powered Handheld Instrument, Legacy Computer Peripheral Interface, Test and Measurement Equipment.
Industrial RS232 Serial Port
The LT1080CJ fits industrial serial port designs where reliable 5V RS232 communication is required between a microcontroller/UART and external equipment. The part supports data rates above 120 kBaud, which covers all common industrial baud rates from 9600 to 115200, and its ±30V driver output tolerance protects against shorts and transients on cables in factory environments. The on-chip charge pump generates ±10V RS232 levels from a single 5V rail, simplifying power design in PLCs, HMIs, and motor drives. The CERDIP package is preferred for high-reliability industrial applications.
Recomendado
Point-of-Sale (POS) Terminal
The LT1080CJ is well suited for POS terminal designs that need a 5V RS232 port for cash drawers, barcode scanners, receipt printers, and legacy peripherals. The part's single 5V supply operation matches the 5V rails common in POS embedded designs, and the integrated charge pump eliminates the need for a negative supply. The 2-driver/2-receiver configuration supports a full-duplex serial channel (TX, RX) plus hardware flow control (RTS, CTS), matching standard RS232 cable pinouts. The shutdown pin allows the POS terminal to power down the RS232 link when not in use to reduce standby current.
Recomendado
Embedded System Debug Console
The LT1080CJ provides a robust 5V RS232 debug console interface for embedded development boards and production test equipment. The part connects the target MCU's UART to a host PC's COM port, allowing printf-style debugging and firmware updates over a standard DB9 cable. Its data rate above 120 kBaud supports high-speed console output (up to 115200 baud) without bottlenecking logging throughput. The 18-pin CERDIP through-hole package is convenient for breadboard and through-hole prototype designs, while the LT1080CSW#PBF (SO-18) variant is preferred for SMT-based production designs.
Recomendado
Battery-Powered Handheld Instrument
The LT1080CJ suits battery-powered handheld instruments that require an RS232 port for configuration, calibration, or data transfer. The shutdown pin reduces quiescent current when the serial port is not in use, extending battery life. The single 5V supply operation matches the 5V regulated rails in many handheld designs powered by 4xAA cells or Li-ion with a boost converter. The ±30V driver output tolerance protects against ESD events and cable miswiring that can occur in field-deployed instruments. The CERDIP package is preferred for high-shock and high-vibration handheld environments.
Recomendado
Legacy Computer Peripheral Interface
The LT1080CJ provides a modern, low-power 5V RS232 interface for legacy peripheral equipment, including industrial printers, scales, scientific instruments, and medical devices with DB9 serial ports. The on-chip charge pump and small 1µF capacitors simplify the power design, and the part's superior ESD/overvoltage tolerance protects against cable miswiring in installed equipment. The CERDIP package is preferred for legacy equipment refurbishment where original parts used DIP packages, allowing drop-in replacement of older MAX232/MAX202 designs on the same PCB footprint (with pinout verification).
Recomendado
Test and Measurement Equipment
The LT1080CJ is appropriate for bench-top test and measurement equipment that interfaces with a host computer via RS232 for automated test, calibration, or data logging. The 5V single-supply operation simplifies the internal power tree, and the >120 kBaud data rate supports fast data transfer from instruments like multimeters, oscilloscopes, and signal generators. The three-state driver outputs and shutdown pin allow the RS232 port to share a bus with other instruments or to be powered down when not in use, reducing thermal load in enclosed test equipment. The CERDIP package is preferred for high-reliability laboratory and production test systems.
Recomendado
Resumo dos produtos recomendados
Dados de referência de engenharia para LT1080CJ — comparação, orientação de projeto e informações de conformidade.
Guia de seleção
Comparação com alternativas
| Parâmetro | Este produto | LT1080CN#PBF | LT1080CSW#PBF | LT1180CJ | LT1080IN#PBF | ADM232AANZ | MAX232CPE+ | MAX232IN |
|---|---|---|---|---|---|---|---|---|
| Brand | Linear Technology | Linear Technology | Linear Technology | Linear Technology | Linear Technology | Analog Devices | Maxim Integrated | Maxim Integrated |
| Package | CERDIP-18 (J) | PDIP-18 - same pinout | SOIC-18 - same pinout | CERDIP-18 - same | PDIP-18 - same pinout | PDIP-18 - same pinout | PDIP-18 - same pinout | PDIP-18 - same pinout |
| Function | RS232 2D/2R Transceiver | RS232 2D/2R - same | RS232 2D/2R - same | RS232 5D/3R Transceiver | RS232 2D/2R - same | RS232 2D/2R - same | RS232 2D/2R - same | RS232 2D/2R - same |
| Supply Voltage | 5 V (single) | 5 V - same | 5 V - same | 5 V - same | 5 V - same | 5 V - same | 5 V - same | 5 V - same |
| Shutdown Pin | Yes (SD) | Yes - same | Yes - same | Yes - same | Yes - same | No | No | No |
| Charge Pump Caps | 4 x 1 µF | 4 x 1 µF - same | 4 x 1 µF - same | 4 x 1 µF - same | 4 x 1 µF - same | 4 x 1 µF - same | 4 x 1 µF - same | 4 x 1 µF - same |
| Operating Temperature | 0°C to +70°C (commercial) | 0°C to +70°C - same | 0°C to +70°C - same | 0°C to +70°C - same | -40°C to +85°C (industrial) | -40°C to +85°C | 0°C to +70°C | -40°C to +85°C |
| Approx. Unit Price (qty 1) | $15.05 | Lower (plastic DIP) | Lower (SOIC) | Higher | Higher (industrial) | Comparable | Lower (industry-standard) | Comparable |
Principais diferenciais
- Shutdown pin with tri-state driver outputs (vs MAX232CPE+)
- CERDIP package for high-reliability applications (vs LT1080CN#PBF (PDIP))
- 2-driver/2-receiver configuration matches standard RS232 (vs LT1180CJ (5D/3R))
Notas de projeto
Place the four 1µF charge-pump capacitors (C1, C2) as close to the LT1080CJ pins (C1+, C1-, C2+, C2-, V+, V-) as possible. Use ceramic capacitors with low ESR (X5R or X7R dielectric) to minimize ripple on the generated ±10V rails. Keep capacitor trace lengths under 5mm to avoid noise coupling into the driver outputs, which can degrade RS232 signal integrity at high data rates.
Do not leave the SD (shutdown) pin floating. According to the datasheet, the SD pin must be driven logic-low for normal operation and logic-high for shutdown. If the pin is not used, tie it to GND through a 10kΩ resistor to prevent accidental shutdown from noise. Also, the driver outputs can be forced to ±30V without damage, but prolonged overvoltage may stress the charge pump - check the absolute maximum ratings in the datasheet.
Separate the analog/digital ground plane under the LT1080CJ from the chassis/shield ground of the RS232 cable. Connect the two grounds at a single point near the LT1080CJ GND pin. The CERDIP package lead frame provides good thermal conductivity, so a small copper pour on the GND pins helps with thermal dissipation in high-data-rate applications. For surface-mount designs, the LT1080CSW#PBF (SO-18) variant uses the same pinout with a smaller footprint.
Informações de conformidade
CERDIP package (J suffix) typically uses SnPb (tin-lead) leads and is not RoHS compliant. For Pb-free/RoHS-compliant designs, choose the LT1080CN#PBF (PDIP) or LT1080CSW#PBF (SOIC) variants from the same family. The CERDIP package is preferred for military and high-reliability applications where RoHS exemptions apply.
