Diodes Incorporated APX803L-21W5-7

Overview

APX803L-21W5-7 from Diodes Incorporated is a micro-power voltage detector IC designed for µP supervisory circuits, monitoring VCC supply rails in embedded and battery-powered systems. It features a fixed 2.1V detection threshold (±1.5% accuracy), 1µA typical supply current, open-drain active-low RESET output, and 220ms reset timeout - enabling reliable power-on reset and brownout protection in portable instrumentation and IoT edge nodes.

For engineers reviewing the APX803L-21W5-7 datasheet, APX803L-21W5-7 pinout, APX803L-21W5-7 application, or APX803L-21W5-7 equivalent, key selection considerations include its SOT25 package compatibility, 220ms delay option, low-quiescent-current operation under 1.0V to 5.5V supply range, and guaranteed reset assertion within 20µs of VCC drop below threshold.

Technical Context

The APX803L-21W5-7 implements a precision bandgap-based voltage reference with internal hysteresis (0.01×VTH) to prevent oscillation during threshold crossing. Its comparator drives an open-drain NMOS output stage capable of sinking ≥3.5mA at 0.4V max VOL, supporting direct interface to µP reset inputs without external pull-up constraints.

Reset assertion is triggered when VCC falls below 2.1V and remains active until VCC rises above 2.115V (typical hysteresis), with built-in 220ms timeout ensuring sufficient system stabilization before release - validated across –40°C to +85°C operating ambient.

Key Specifications

Pinout & Package

SOT25 (5-pin) package with 3 functional terminals and 2 no-connect pins - optimized for board space efficiency while maintaining robust thermal performance (θJA = 200°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3808G21DBVR and MAX809SEUR+T, the APX803L-21W5-7 delivers tighter threshold accuracy (±1.5% vs ±2.5%), lower supply current (1µA vs 10µA), and a compact SOT25 footprint with dedicated NC pins for improved noise immunity - making it optimal for space-constrained, ultra-low-power applications requiring deterministic 220ms reset timing.

Availability

APX803L-21W5-7 is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, smart home hub controllers, and asset tracking beacons requiring stable component supply with guaranteed long-term manufacturability.

Supply support for APX803L-21W5-7 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 solutions for power management, signal integrity, and connectivity applications.

The APX803L series belongs to Diodes' precision voltage supervisor product line, engineered specifically for ultra-low-power, high-accuracy power monitoring in battery-operated and energy-sensitive embedded systems.

FAQ

What is the exact reset threshold voltage and tolerance for APX803L-21W5-7?

The APX803L-21W5-7 has a factory-trimmed detection threshold of 2.1V with a guaranteed accuracy of ±1.5% over –40°C to +85°C ambient temperature. This corresponds to a minimum threshold of 2.0685V and maximum of 2.1315V at +25°C, with temperature coefficient of 50ppm/°C ensuring stability across operating conditions.

Can APX803L-21W5-7 operate with supply voltages below 1.0V?

No - the APX803L-21W5-7 requires a minimum VCC of 0.9V to function, but its specified recommended operating range starts at 1.0V. Below 1.0V, internal reference and comparator performance is not guaranteed; the device will not assert RESET reliably, and supply current may deviate from datasheet specs.

Is the 220ms reset timeout adjustable or fixed?

The 220ms timeout is factory-fixed and non-adjustable. It is implemented via internal RC timing and calibrated during production - no external components or configuration pins are required or supported. The "20" in the part number (APX803L20-21W5-7) explicitly denotes this 220ms variant.

How does the open-drain RESET output interface with a 1.8V microcontroller?

The open-drain RESET output can be pulled up to any valid logic voltage (e.g., 1.8V) using an external resistor (typically 10kΩ). When asserted, the output sinks current and pulls the node to ≤0.4V (at 3.5mA sink), satisfying VIH/VIL requirements of 1.8V I/O standards. No level-shifting circuitry is needed.