LT1030CN - Quad RS-232 Line Driver, ±15V, 14-PDIP | TI
MPN: LT1030CN ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.15 | $3.15 |
| 10 | $2.84 | $28.40 |
| 100 | $2.5 | $250.00 |
| 500 | $2.18 | $1,090.00 |
| 1,000 | $1.84 | $1,840.00 |
LT1030CN Overview
A line driver is a unidirectional buffer that translates low-voltage logic levels (such as 0/5 V CMOS or 0/3.3 V LVTTL) into the higher-voltage swings required by serial-interface standards. RS-232 is the most widely deployed single-ended asynchronous serial standard, historically using ±12 V signaling to provide noise immunity over cables up to ~15 m. The LT1030CN belongs to the EIA/TIA-232-F line-driver category within the broader interface-IC family, which sits above simple transceivers in the protocol-IC hierarchy because it provides drivers only (no receivers) and is intended to be paired with a separate receiver IC such as the LT1031C.
Key features of the LT1030CN include: ±5 V to ±15 V supply range, 500 µA typical supply current, zero supply current in shutdown, ±30 V output overvoltage protection, 10 mA minimum output drive, parallelable outputs for higher drive, and compliance with ANSI EIA/TIA-232-F. The shutdown (SHDN) pin enables power-saving modes in battery-powered terminals, and the 3-state output behavior prevents back-driving when the device is off.
The LT1030 architecture uses a charge-pump-free, low-power bipolar driver design that does not require external capacitors; the output stage is built with Darlington-style pull-down and active pull-up devices to achieve the wide ±15 V compliance. Designers should note that the bipolar front-end consumes more quiescent current than CMOS-only alternatives but provides robust ±30 V fault tolerance that is difficult to match with purely CMOS parts.
Typical applications for the LT1030CN include: RS-232 driver-only channels where a separate receiver IC is already present, point-of-sale terminals, industrial serial-port modules, battery-powered portable instruments, and legacy peripheral interfaces requiring ±12 V signaling. The 14-PDIP through-hole package simplifies prototyping, rework, and breadboarding versus surface-mount alternatives.
When designing with the LT1030CN, place a 0.1 µF bypass capacitor close to each supply pin (V+ and V-) and observe the 10 mA minimum-load requirement on the EIA/TIA-232-F receivers it drives. To shut down the device, pull the SHDN pin high; leaving it floating or grounded keeps the outputs active. Do not exceed ±30 V on any driver output, even though internal current limiting will protect the device.
Drop-in alternatives for LT1030CN — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
LT1030CN#PBF
✅ Drop-In📋 Reference alternative (not in catalog)
LT1030CNE4
✅ Drop-In📋 Reference alternative (not in catalog)
LT1030IN
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
LT1030MJ
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
LT1030CN Specifications
| Function | Quad RS-232 Line Driver (4 drivers / 0 receivers) |
| Protocol | EIA/TIA-232-F, RS-232 |
| Number of Drivers | 4 |
| Supply Voltage Range | ±5 V to ±15 V |
| Supply Current (typical) | 500 µA |
| Supply Current (shutdown) | 0 µA (zero supply current) |
| Output Drive Current (min) | 10 mA |
| Output Voltage Tolerance (externally applied) | ±30 V |
| Output Swing to V+ | Within 200 mV |
| Output Swing to V- | Within 1 V |
| Data Rate | 120 kb/s |
| Shutdown Pin | Yes (logic high = shutdown, 3-state outputs) |
| Output Configuration When Off | High impedance (3-state) |
| Operating Temperature Range | 0 °C to +70 °C |
| Package | 14-pin PDIP (N) |
| Mounting Type | Through-Hole |
| RoHS Status | Compliant |
LT1030CN Pin Configuration
| Pin 1 | 1OUT — Driver 1 output (RS-232 level) |
| Pin 2 | 1IN — Driver 1 logic input (TTL/CMOS) |
| Pin 3 | 2OUT — Driver 2 output (RS-232 level) |
| Pin 4 | 2IN — Driver 2 logic input (TTL/CMOS) |
| Pin 5 | 3OUT — Driver 3 output (RS-232 level) |
| Pin 6 | 3IN — Driver 3 logic input (TTL/CMOS) |
| Pin 7 | 4OUT — Driver 4 output (RS-232 level) |
| Pin 8 | 4IN — Driver 4 logic input (TTL/CMOS) |
| Pin 9 | GND — Ground (0 V reference) |
| Pin 10 | V- — Negative supply (typically -5 V to -15 V) |
| Pin 11 | SHDN — Active-high shutdown (logic high = 3-state outputs, zero Iq) |
| Pin 12 | NC — Not connected (per datasheet) |
| Pin 13 | V+ — Positive supply (typically +5 V to +15 V) |
| Pin 14 | NC — Not connected (per datasheet) |
Typical Applications
LT1030CN is suitable for 6 applications: RS-232 Communication Ports in Industrial Equipment, Point-of-Sale (POS) Terminals, Battery-Powered Portable Serial Instruments, Legacy Peripheral and Modem Interfaces, Test and Measurement Equipment Front Panels, Aerospace Avionics Serial Buses.
RS-232 Communication Ports in Industrial Equipment
The LT1030CN is widely used in industrial serial-port modules that require robust ±12 V RS-232 signaling over cables up to 15 m. Its 4-driver output stage and ±30 V overvoltage protection make it tolerant of mis-wiring and ESD transients common in factory-floor installations. The 14-PDIP package simplifies through-hole assembly for control panels, PLCs, and motor-drive serial debug ports. The 500 µA quiescent current is acceptable for line-powered equipment, and the 120 kbps data rate easily supports legacy industrial protocols such as Modbus RTU. Designers can pair the LT1030CN with the LT1031C receiver to form a complete 4-channel RS-232 channel.
Recommended
Point-of-Sale (POS) Terminals
POS terminals and electronic cash registers often use the LT1030CN to provide EIA/TIA-232-F drive on serial ports connected to receipt printers, barcode scanners, and PIN pads. The driver's ability to source 10 mA per channel ensures reliable signaling even with the 3 kΩ to 7 kΩ input impedance of legacy serial peripherals. The wide ±15 V supply range accepts the ±12 V rails typically already present in POS mainboards that also power other interface circuitry. Combined with its 0/70 °C commercial temperature range and 14-PDIP package, the LT1030CN remains a cost-effective choice for high-volume POS hardware that is field-serviceable through-hole design.
Recommended
Battery-Powered Portable Serial Instruments
The LT1030CN suits battery-powered handheld instruments (data loggers, diagnostic tools, field-service terminals) because of its 500 µA typical quiescent current and zero supply current in shutdown. Asserting the SHDN pin drops the supply current to zero between transmissions, extending battery life. The 14-PDIP package works well for prototype and low-volume hand-held enclosures. The ±30 V fault tolerance protects the driver from cable mis-wiring in the field, and the 120 kbps data rate supports all standard Modbus, NMEA, and proprietary serial protocols used in field instrumentation.
Recommended
Legacy Peripheral and Modem Interfaces
The LT1030CN provides the 4 driver channels needed to interface to legacy DB-9 RS-232 modems, terminal servers, and industrial peripherals that require the original ±12 V signaling levels. With output swings within 200 mV of V+ and 1 V of V-, the driver delivers the full EIA/TIA-232-F voltage range needed for proper noise immunity over 15-meter cables. Multiple LT1030CN outputs can be paralleled for higher drive if the load is heavier than 3 kΩ. The 14-PDIP package is the most field-replaceable option for legacy equipment that is still in service decades after deployment.
Recommended
Test and Measurement Equipment Front Panels
Bench-top test instruments (oscilloscope service ports, spectrum-analyzer remote interfaces, lab data-acquisition front-ends) often use the LT1030CN to drive RS-232 service or SCPI command ports. The bipolar driver's ±30 V fault tolerance is valuable in lab environments where cables are frequently swapped and ground loops can apply large transients. The 500 µA quiescent current is negligible compared to the rest of the instrument, and the 14-PDIP package allows easy rework on long-life test equipment that may be serviced for 20+ years.
Recommended
Aerospace Avionics Serial Buses
The hermetic-ceramic LT1030MJ variant (also derived from the same die) is used in avionics and military serial interfaces where -55 °C to +125 °C operation is required. Although the standard LT1030CN is 0/70 °C, the family is MIL-STD-883 screened in some procurement flows. The driver's high immunity to externally applied ±30 V and the EIA/TIA-232-F compliance suit the long cable runs and noisy electrical environments of aircraft and ground-vehicle platforms. Designers should consult the TI military product drawing for the exact screening flow and pinout tolerances.
Recommended
Recommended Products Summary
Engineering reference data for LT1030CN — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LT1030CN#PBF | LT1030CNE4 | LT1030IN | LT1030MJ |
|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments (Analog Devices Inc. branded) | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 14-PDIP (N) | 14-PDIP (N) - same | 14-PDIP (N) - same | 14-PDIP (N) - same | 14-CDIP (J) - same pin pitch, ceramic body |
| Number of Drivers / Receivers | 4 / 0 | 4 / 0 | 4 / 0 | 4 / 0 | 4 / 0 |
| Supply Voltage Range | ±5 V to ±15 V | ±5 V to ±15 V | ±5 V to ±15 V | ±5 V to ±15 V | ±5 V to ±15 V |
| Quiescent Supply Current (typ) | 500 µA | 500 µA | 500 µA | 500 µA | 500 µA |
| Output Overvoltage Tolerance | ±30 V | ±30 V | ±30 V | ±30 V | ±30 V |
| Operating Temperature Range | 0 °C to +70 °C | 0 °C to +70 °C | 0 °C to +70 °C | -40 °C to +85 °C (industrial) | -55 °C to +125 °C (military) |
| Lead-Free / RoHS | Yes (E4 finish) | Yes (PBF finish, lead-free) | Yes (E4 finish, lead-free) | Yes (lead-free) | Hermetic, no lead-free required |
Key Differentiators
- Driver-only (4/0) architecture enables flexible receive-side placement (vs MAX202 / MAX232 (integrated 2-driver + 2-receiver transceivers))
- Wide ±30 V output fault tolerance without external protection (vs MAX222 / MAX232 (±15 V typical external tolerance))
- Zero-power shutdown mode for battery designs (vs MAX202 (no dedicated shutdown pin in older revisions))
Design Notes
The LT1030CN requires both a positive supply (V+, pins 13) and a negative supply (V-, pin 10) in the ±5 V to ±15 V range. Unlike modern charge-pump transceivers such as the MAX232, it does not generate its own negative rail, so the system must already have a negative supply available (typically a small isolated DC-DC converter or a transformer-derived ±12 V). Place a 0.1 µF ceramic bypass capacitor close to each of the V+ and V- pins, and a 1 µF to 10 µF bulk tantalum/ceramic across the supplies to handle the 10 mA output current transients. The shutdown pin (SHDN, pin 11) is active-high; tie it to GND through a 100 kΩ pull-down if shutdown is not used to keep the part enabled by default.
Do not confuse the LT1030CN (driver only, 4/0) with the LT1031CN (receiver only, 0/4) or with a full RS-232 transceiver such as the MAX232. The LT1030CN provides 4 drivers but no receivers, so it cannot receive RS-232 data on its own - a separate receiver IC must be used in conjunction with it. A common mistake is to assume the SHDN pin behaves as a logic-low enable; the datasheet specifies that SHDN is active-high (logic high = outputs in 3-state, supply current = 0). Leave SHDN floating or tied to GND for normal operation. Also note that the EIA/TIA-232-F standard requires the driver to sink/source at least 3 kΩ; the LT1030CN delivers 10 mA minimum, which exceeds this requirement with comfortable margin.
The 14-PDIP (N) package is through-hole with standard 2.54 mm (0.1 inch) pin pitch and 7.62 mm (0.3 inch) row spacing. Keep the V+ and V- traces wide (at least 0.5 mm or 20 mil) to handle the 10 mA peak output current without significant voltage drop. Place a 0.1 µF bypass cap within 5 mm of each supply pin to suppress switching transients when multiple drivers toggle simultaneously. If the design is in a noisy industrial environment, add a ferrite bead in series with each V+ and V- pin between the bypass cap and the IC to suppress high-frequency noise. Inputs (1IN-4IN) are high-impedance TTL/CMOS-compatible and may be driven directly from a 3.3 V MCU without level shifting.
Compliance Information
RoHS compliant when ordered as LT1030CN#PBF or LT1030CNE4. The original LT1030CN (no suffix) uses SnPb finish and is not RoHS compliant. AEC-Q100 is not applicable - this is a commercial-grade interface IC; for automotive RS-232 needs use the TJA1021T/20/C (LIN) or MAX3160EAP+ (RS-232/RS-485).
