Diodes Incorporated APX803L40-37SA-7

Overview

APX803L40-37SA-7 from Diodes Incorporated is a micro-power voltage detector IC designed for µP supervisory circuits, providing 4.0V fixed threshold detection with ±1.5% accuracy, 450ms reset timeout, and 1µA typical supply current in SOT23-3 package. It delivers active-low open-drain reset signaling for power monitoring in battery-powered IoT sensors and portable medical devices.

For engineers reviewing the APX803L40-37SA-7 datasheet, APX803L40-37SA-7 pinout, APX803L40-37SA-7 application, or APX803L40-37SA-7 equivalent, this page provides verified functional specifications, validated pin mapping, confirmed timing behavior under VCC droop, and real-world use cases in low-power embedded systems requiring reliable brown-out detection.

Technical Context

The APX803L40-37SA-7 implements a precision bandgap-based voltage reference with internal hysteresis (0.01×VTH) to prevent reset chatter during slow VCC recovery. Its comparator output drives an open-drain RESET pin that remains asserted until VCC exceeds 4.0V + hysteresis (≈4.064V).

It integrates a factory-trimmed 450ms reset timeout (typ.) after VCC recovery, independent of external components, and operates across -40°C to +85°C ambient with 50 ppm/°C threshold temperature coefficient - enabling stable supervision in thermally variable handheld electronics.

Key Specifications

Pinout & Package

SOT23-3 package (3-pin, 1.3mm × 2.9mm, 0.95mm height), RoHS-compliant, lead-free, halogen-free "Green" construction.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage supervisor applications.

Compared with APX803L40-29SA-7, the -37SA-7 extends reset hold time for slower peripherals; versus TLV803E40DBZR, it trades 0.4µA higher ICC for broader Diodes' qualification support and established field reliability in industrial designs.

Availability

APX803L40-37SA-7 is available at Aetrix Electronics and suitable for wearable health monitors, smart home sensor nodes, industrial data loggers, and portable diagnostic tools requiring stable component supply across extended product lifecycles.

Supply support for APX803L40-37SA-7 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

Diodes Incorporated is a global semiconductor company specializing in discrete, analog, and mixed-signal ICs for power management, signal integrity, and protection applications.

The APX803L series belongs to Diodes' µP supervisory product line, engineered specifically for ultra-low-power, high-accuracy voltage monitoring in battery-constrained and thermally demanding embedded systems.

FAQ

What is the exact reset timeout value for APX803L40-37SA-7?

The APX803L40-37SA-7 features a factory-set reset timeout of 450ms (typical), with guaranteed minimum 292ms and maximum 608ms across temperature and process variation. This delay begins when VCC rises above the 4.0V threshold and ends when RESET transitions high (open-drain released).

Can APX803L40-37SA-7 monitor a 1.8V supply rail?

No - the APX803L40-37SA-7 has a fixed 4.0V detection threshold and requires VCC ≥ 0.9V to operate, but it only asserts RESET when the monitored rail falls below 4.0V. To supervise a 1.8V rail, a 1.8V-threshold variant (e.g., APX803L18-XXSA-7) must be selected.

Is an external pull-up resistor required on the RESET pin?

Yes - the RESET pin is open-drain and active-low. A pull-up resistor (typically 10kΩ to VCC or host logic rail) is mandatory to establish a defined high state when RESET is not asserted. No internal pull-up exists.

Does APX803L40-37SA-7 support operation at -40°C?

Yes - the device is fully specified from -40°C to +85°C ambient temperature. Electrical characteristics including threshold accuracy (±1.5%), timeout (450ms typ.), and supply current (1µA typ.) are guaranteed across this full industrial temperature range.