STMicroelectronics ST232ABTR

Overview

ST232ABTR from STMicroelectronics is a dual-transmitter/dual-receiver RS-232 interface IC operating from a single 5 V supply, compliant with EIA/TIA-232 and V.28 standards. It delivers ±9 V transmitter output swing, 400 kbps data rate, 0.1 µs receiver propagation delay, and draws only 1.5 mA supply current at no load-enabling low-power RS-232 communication in space-constrained portable systems.

For engineers reviewing the ST232ABTR datasheet, ST232ABTR pinout, ST232ABTR application, or ST232ABTR equivalent, key selection criteria include its TSSOP16 package, –40 to 85 °C industrial temperature range, integrated charge-pump voltage generation requiring only four 0.1 µF capacitors, and TTL/CMOS-to-RS-232 level translation capability without ±12 V rails.

Technical Context

The ST232ABTR integrates two independent RS-232 transmitters and receivers on a single die, using on-chip charge-pump circuitry to generate ±V_CC-derived voltages (V+ and V−) from a 5 V input. Its receiver input tolerance of ±30 V and hysteresis of 0.2–1 V ensure robust noise immunity in electrically noisy environments.

Transmitter outputs drive standard 3 kΩ RS-232 loads with 12 V/µs typical slew rate and ±9 V swing, while receiver outputs deliver TTL/CMOS-compatible logic levels (V_OH ≥ 3.5 V, V_OL ≤ 0.4 V) directly compatible with microcontrollers and FPGAs without level-shifting buffers.

Key Specifications

Pinout & Package

TSSOP16 (Thin Shrink Small Outline Package, 16-pin), lead-free ECOPACK® compliant, 4.4 mm × 5.0 mm body, 0.65 mm pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar RS-232 transceiver applications.

Compared with MAX3232ESE+ and SP3232EEN-L, the ST232ABTR uniquely combines industrial temperature range (–40 to 85 °C), 400 kbps speed, and 1.5 mA supply current in a TSSOP16 package-making it optimal for battery-powered industrial edge devices requiring long-term reliability under thermal stress.

Availability

ST232ABTR is available at Aetrix Electronics and suitable for portable data terminals, industrial PLC serial interfaces, and battery-powered sensor gateways requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for ST232ABTR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, mixed-signal, power, and microcontroller products for industrial, automotive, and consumer markets.

The ST232ABTR belongs to ST's RS-232 interface product line, engineered specifically for low-power, single-supply serial communication in space- and energy-constrained embedded systems.

FAQ

What is the minimum number and value of external capacitors required for ST232ABTR operation?

The ST232ABTR requires exactly four 0.1 µF ceramic capacitors (C1–C4) connected to pins C1+, C1−, C2+, and C2−. These form the charge-pump network generating V+ and V−. Using values outside 0.1 µF may degrade output voltage swing or increase supply current; ST specifies 0.1 µF as optimal for ±9 V output and 1.5 mA quiescent draw.

Does ST232ABTR support automatic power-down or shutdown mode?

No, the ST232ABTR does not include a hardware shutdown pin or automatic power-down feature. It operates continuously when VCC is applied. For low-power sleep states, system-level control must disable VCC via an external load switch or PMIC-since the device draws only 1.5 mA at no load, this is often unnecessary in most industrial applications.

Can ST232ABTR drive standard RS-232 loads over 15-meter cables?

Yes, the ST232ABTR's ±9 V output swing and 300 Ω transmitter output resistance meet EIA/TIA-232 requirements for driving up to 15 m of standard 24 AWG twisted-pair cable at 400 kbps. Signal integrity depends on proper termination and grounding; ST recommends using shielded cable and keeping receiver input traces short to maintain noise immunity.

Is ST232ABTR pin-compatible with older ST232 series variants like ST232CDR?

No, ST232ABTR is not pin-compatible with ST232CDR. While both are 16-pin RS-232 transceivers, ST232CDR uses SO-16 packaging and has different temperature grading (0 to 70 °C), whereas ST232ABTR is TSSOP16 and rated for –40 to 85 °C. Pin functions match per datasheet Table 2, but mechanical layout and thermal characteristics differ significantly.