Diodes Incorporated APX803S05-23SA-7

Overview

APX803S05-23SA-7 from Diodes Incorporated is a 3-pin SOT23 open-drain microprocessor reset supervisor IC designed for 2.25V supply monitoring in embedded digital systems. It asserts an active-low RESET signal during power-up, brownout, or VCC drop below 2.25V (±0.04V), maintains reset for 50ms (typ.) after VCC recovers, and operates reliably down to VCC = 1V with 10µA typical supply current. Used in portable controllers and battery-powered instrumentation.

For engineers reviewing the APX803S05-23SA-7 datasheet, APX803S05-23SA-7 pinout, APX803S05-23SA-7 application, or APX803S05-23SA-7 equivalent, key selection criteria include reset threshold accuracy (2.21–2.30V), timeout duration (20–70ms), open-drain drive capability (3.5mA sink at 0.4V), guaranteed operation to 1V VCC, and SOT23-3 SA package compatibility.

Technical Context

The APX803S05-23SA-7 implements a precision voltage comparator with 30ppm/°C tempco and internal fixed-delay timer to generate a deterministic reset pulse. Its open-drain output requires an external pull-up and supports bidirectional reset interfacing with µCs like the Motorola 68HC11.

It ignores fast VCC transients and guarantees valid logic state (RESET low) for VCC ≥ 1V; below 1V, RESET becomes high-impedance. The device is fully specified across –40°C to +85°C and consumes ≤15µA max supply current.

Key Specifications

Pinout & Package

APX803S05-23SA-7 is housed in a RoHS-compliant, halogen-free SOT23-3 (SA) package with 2.9mm × 1.3mm footprint and 0.95mm height. Pin 1 is GND, Pin 2 is VCC, Pin 3 is open-drain RESET - confirmed per Diodes DS39161 Rev. 2-2 top-view diagram and ordering table.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microprocessor reset supervision applications.

Compared with APX803S05-23SA-7, the APX809S23-23SA-7 simplifies BOM by removing the pull-up resistor but sacrifices bus-sharing flexibility, while the MAX809SEUR+T shifts threshold upward by 250mV and doubles timeout-both changes require validation against system-level reset timing and supply tolerance budgets.

Availability

APX803S05-23SA-7 is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, smart meter communication units, and automotive body control modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for APX803S05-23SA-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 manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability power management, signal integrity, and protection solutions for industrial, computing, and consumer markets.

The APX803S series belongs to Diodes' µP supervisory product line, engineered specifically for precision voltage monitoring and deterministic reset generation in resource-constrained embedded systems with strict power and footprint requirements.

FAQ

What is the exact reset threshold voltage range for APX803S05-23SA-7?

The APX803S05-23SA-7 has a guaranteed reset threshold range of 2.21V to 2.30V at +25°C, with ±0.04V tolerance centered on 2.25V. Over the full –40°C to +85°C operating range, the threshold drift is limited to ±11.4mV due to its 30ppm/°C tempco, ensuring consistent brownout detection across environmental conditions.

Can APX803S05-23SA-7 drive a reset line directly without a pull-up resistor?

No - APX803S05-23SA-7 features an open-drain RESET output and requires an external pull-up resistor to a valid logic supply (e.g., the monitored VCC or another system rail). Typical values range from 10kΩ to 100kΩ depending on bus capacitance and µP input leakage; absence of the pull-up results in undefined logic state on the reset line.

How does the 50ms reset timeout behave during repeated brownouts?

Each time VCC falls below the 2.21–2.30V threshold, the internal timer resets and restarts. RESET remains asserted low for the full 20–70ms window after VCC rises above the threshold - even if multiple dips occur. This prevents premature release of reset during unstable supply conditions, ensuring µP remains held until stable operation is confirmed.

Is APX803S05-23SA-7 compatible with 1.8V microcontrollers?

Yes - although it monitors a 2.25V supply, its RESET output is valid down to VCC = 1.0V and can interface with 1.8V µPs via appropriate pull-up voltage (e.g., to 1.8V rail). The open-drain architecture allows level translation; however, the monitored supply must remain ≥2.21V for correct threshold detection - it does not supervise 1.8V rails directly.