Texas Instruments TMP392A3DRLT

Overview

TMP392A3DRLT from Texas Instruments is a dual-channel, resistor-programmable temperature switch with independent hot (Channel A: +30°C to +124°C) and warm (Channel B: +30°C to +105°C) overtemperature detection, ±3.5°C trip accuracy (±2.0°C from +30°C to +70°C), 0.5µA typical quiescent current at 25°C, and open-drain outputs-used in DC/DC converters and power tools for thermal fault protection.

For engineers reviewing the TMP392A3DRLT datasheet, TMP392A3DRLT pinout, TMP392A3DRLT application, or TMP392A3DRLT equivalent, this page delivers verified technical context, resistor-programming constraints, hysteresis configuration options (5°C/10°C/20°C), SOT-563 package layout guidance, and real-world thermal trip test implementation details.

Technical Context

The TMP392A3DRLT implements two independent thermal comparators with external E96-series (1%) resistors on SETA and SETB pins to set trip thresholds and select hysteresis-5°C or 10°C for both channels, or 20°C on Channel A only when SETB is grounded. It operates across –55°C to +130°C with 0.65ms conversion time and 0.5s sampling period.

Its ultra-low-power architecture uses standby mode between conversions, drawing just 0.5µA typical at 25°C and 1µA max across full temperature and supply range (1.62V–5.5V). The device supports in-system trip testing by asserting logic high on SETA or SETB to force corresponding open-drain outputs low without thermal cycling.

Key Specifications

Pinout & Package

SOT-563 (DRL) 6-pin package: 1.60mm × 1.20mm footprint with 0.5mm pitch-designed for space-constrained applications including power tool PCBs and compact DC/DC modules.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel temperature switch applications.

Compared with TMP390DRLT and MAX6581AUT+T, the TMP392A3DRLT uniquely delivers resistor-programmable hot/warm thresholds with ultra-low power and zero-software overhead-making it the only choice for cost-sensitive, space-constrained, and battery-operated thermal protection where deterministic analog response is mandatory.

Availability

TMP392A3DRLT is available at Aetrix Electronics and suitable for DC/DC converters, power tools, and lighting control systems requiring stable component supply, long-term lifecycle support, and guaranteed traceability for industrial production programs.

Supply support for TMP392A3DRLT 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

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and connectivity technologies-with broad portfolio coverage in precision sensing, power management, and industrial interface solutions.

The TMP392A3DRLT belongs to TI's ultra-low-power temperature switch family, designed specifically for hardware-based thermal protection in space- and energy-constrained applications such as portable power tools, compact power supplies, and LED lighting systems.

FAQ

What is the trip temperature accuracy specification for TMP392A3DRLT?

The TMP392A3DRLT has a maximum trip point accuracy of ±3.5°C across +30°C to +130°C, and ±2.0°C from +30°C to +70°C. This A3-level accuracy is specified under recommended operating conditions (VDD = 1.62V–5.5V, TA = –55°C to +130°C) and reflects worst-case deviation from nominal resistor-programmed thresholds. Accuracy is independent of resistor tolerance due to TI's ratiometric architecture-only resistor value matters, not its 1% tolerance.

How does the hysteresis selection work on TMP392A3DRLT?

Hysteresis on the TMP392A3DRLT is selected solely by the resistor value on the SETB pin: 5°C or 10°C hysteresis applies to both Channel A and Channel B when SETB is connected to a resistor; 20°C hysteresis applies only to Channel A when SETB is grounded. The hysteresis value is fixed per resistor selection-no register writes or external signals are needed. Table 6-2 in the datasheet maps exact resistor values to hysteresis and warm-channel trip points.

Can TMP392A3DRLT operate with only one channel enabled?

Yes. The TMP392A3DRLT supports single-channel operation: grounding or floating SETB disables Channel B and sets Channel A hysteresis to 20°C; grounding or floating SETA disables Channel A while preserving Channel B functionality. Each channel operates independently-disabling one does not affect the other's accuracy, power consumption, or timing behavior. Unused outputs (OUTA or OUTB) may be left floating or tied to GND.

What is the purpose of the trip test function on TMP392A3DRLT?

The trip test function on TMP392A3DRLT allows in-system verification of the entire thermal protection path-including SETA/SETB resistors, pull-up networks, and host interrupt wiring-without thermal cycling. Applying logic high (>0.8 × VDD) to SETA or SETB forces the corresponding output low. This validates board-level assembly integrity during manufacturing and eliminates need for expensive thermal chambers. The test does not alter trip thresholds or hysteresis settings.

What are the minimum and maximum resistor values allowed on SETA and SETB for TMP392A3DRLT?

For TMP392A3DRLT, SETA accepts resistors from 1.05kΩ to 909kΩ (48 discrete values per TI's table), setting Channel A trip from +30°C to +124°C. SETB accepts 10.5kΩ to 909kΩ, setting Channel B trip from +30°C to +105°C and selecting hysteresis. Resistors outside these ranges cause permanent low output on that channel-so design validation must confirm resistor values fall within published bounds before release.