STMicroelectronics ST3241ECPR

Overview

ST3241ECPR from STMicroelectronics is a ±15 kV ESD-protected, 3–5.5 V, 400 kbps RS-232 transceiver with auto power-down, featuring 3 drivers and 5 receivers in SSOP-28 package. It delivers guaranteed 6 V/µs slew rate, 250 kbps minimum data rate, and true RS-232 output levels down to 3 V supply - deployed in battery-powered notebooks and portable peripherals.

For engineers reviewing the ST3241ECPR datasheet, ST3241ECPR pinout, ST3241ECPR application, or ST3241ECPR equivalent, key selection criteria include auto power-down current (1 µA), ESD robustness (±15 kV HBM), dual charge-pump architecture, wake-up receiver R2OUTB, and guaranteed mouse drive capability.

Technical Context

The ST3241ECPR integrates a dual charge-pump circuit generating ±5.5 V rails from 3–5.5 V supply, enabling full RS-232 voltage swing (±5 V min) without external high-voltage supplies. Its proprietary low-dropout transmitter stage maintains compliance across the entire supply range.

Receiver R2 remains active during shutdown to support serial port wake-up; R1 and R2 each provide complementary outputs (R1OUT/R1OUTB, R2OUT/R2OUTB) for noise-immune signal routing. Logic control uses active-low SHDN and EN pins with defined truth table behavior for output tri-state and receiver enable.

Key Specifications

Pinout & Package

ST3241ECPR is housed in a 28-pin SSOP (Shrink Small Outline Package) with 0.65 mm pitch, ECOPACK®-compliant, measuring 10.2 mm × 7.8 mm × 1.75 mm (max height). The package supports automated assembly and provides thermal performance suitable for portable equipment.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX3241CPE+ and SP3241ECA-L, ST3241ECPR uniquely combines 1 µA auto power-down, R2OUTB wake-up output, and 0.1 µF capacitor support in a single SSOP-28 package - delivering superior integration for portable and battery-sensitive designs.

Availability

ST3241ECPR is available at Aetrix Electronics and suitable for notebook computers, industrial HMIs, and handheld test equipment requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for ST3241ECPR 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 microcontrollers, analog ICs, power management devices, and sensors for industrial, automotive, and consumer markets.

The ST3241E series belongs to ST's RS-232 interface product line, engineered specifically for portable and battery-powered systems requiring high ESD immunity, low-power operation, and minimal external component count.

FAQ

What is the minimum supply voltage required for guaranteed RS-232 compliance?

The ST3241ECPR guarantees full RS-232 output swing (±5 V min) and receiver operation down to 3.0 V supply, meeting EIA/TIA-232-F specifications across its entire temperature range (0–70 °C). Below 3.0 V, transmitter output amplitude degrades and is not specified.

How does the auto power-down feature activate?

Auto power-down activates automatically when all transmitter inputs (T1IN–T3IN) are held at logic high for >100 µs, driving supply current to ≤1 µA. No external control signal is needed - the function is internal and transparent to system firmware.

Can ST3241ECPR drive standard RS-232 loads without external components?

Yes - with only four 0.1 µF external capacitors (C1–C4), the ST3241ECPR generates compliant ±5.5 V rails and delivers ±5 V min output swing into 3 kΩ loads, satisfying EIA/TIA-232-F driver requirements without resistors, diodes, or additional regulators.

Is the R2OUTB pin functional during shutdown mode?

Yes - R2OUTB remains active and responsive to RS-232 input signals even when SHDN is asserted (low), enabling hardware wake-up of the host processor without exiting shutdown. This behavior is guaranteed across the full operating temperature range.