Diodes Incorporated APX809S05-23SA-7

Overview

APX809S05-23SA-7 from Diodes Incorporated is a micro-power voltage detector IC designed for µP supervisory functions in +2.5V to +5V digital systems. It provides active-low reset assertion when VCC falls below 2.25V (±30 ppm/°C tempco), maintains reset for ≥240ms after recovery, and operates down to VCC = 1.0V with only 7µA typical supply current. Used in battery-powered controllers and embedded instrumentation for reliable power-on reset.

For engineers reviewing the APX809S05-23SA-7 datasheet, APX809S05-23SA-7 pinout, APX809S05-23SA-7 application, or APX809S05-23SA-7 equivalent, key selection criteria include reset threshold accuracy (2.25V ±30mV), guaranteed reset validity at 1V VCC, push-pull output drive capability (1.2mA sink), temperature-stable timeout (240ms min), and SOT23-3 green package compatibility.

Technical Context

The device implements a precision bandgap-based voltage comparator with hysteresis-free threshold detection and internal timing circuitry to generate a fixed-duration reset pulse. Its reset logic remains valid across the full operating range (−40°C to +125°C) without external components.

Designed for single-supply monitoring, it features a push-pull output stage eliminating need for external pull-up resistors, and includes transient immunity on VCC to suppress false triggering from fast supply noise. The reset timeout is internally generated and independent of external capacitance.

Key Specifications

Pinout & Package

SOT23-3 (SA) package: ultra-compact 2.9mm × 1.3mm surface-mount outline with 0.95mm pitch; RoHS-compliant, halogen-free "Green" molding compound.

Key Features

Applications

Equivalent & Alternatives

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

Compared with APX809S05-23SA-7, the -26 variant shifts threshold upward for tighter margin on 3V rails, while TPS3808G01 offers configurability at the cost of added BOM complexity and different timing behavior-neither replaces the 2.25V/240ms combination without circuit review.

Availability

APX809S05-23SA-7 is available at Aetrix Electronics and suitable for battery-powered instrumentation, industrial microcontroller supervision, and smart sensor node designs requiring stable component supply with guaranteed long-term availability.

Supply support for APX809S05-23SA-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.

This part belongs to the APX809S/810S micro-power voltage detector family, engineered specifically for cost-sensitive, space-constrained µP supervisory applications where precision threshold, low ICC, and push-pull simplicity are critical.

FAQ

What is the minimum VCC voltage at which APX809S05-23SA-7 guarantees correct reset logic state?

The device guarantees valid reset output logic down to VCC = 1.0V, as specified in Recommended Operating Conditions. At this voltage, RESET remains asserted low if VCC is below 2.25V, and transitions correctly when crossing threshold-even during deep brownout conditions common in battery-powered systems.

Does APX809S05-23SA-7 require an external pull-up resistor on the RESET pin?

No. The RESET pin is a push-pull output with integrated driver transistors capable of sinking 1.2mA at ≤0.3V and sourcing current when inactive. This eliminates the need for external pull-up resistors, reducing BOM count and PCB footprint versus open-drain alternatives.

How does the 240ms reset timeout behave across temperature?

The reset timeout remains ≥240ms across the full −40°C to +125°C operating range, with typical values increasing slightly at temperature extremes per performance curves in DS39140 Rev. 2–2. No external capacitor or adjustment is needed-the timing is fully internal and factory-trimmed.

Can APX809S05-23SA-7 monitor a +3.3V supply without modification?

Yes, but with reduced undervoltage margin: its 2.25V threshold provides ~32% headroom below 3.3V, which exceeds typical µP reset margin requirements (e.g., 10–15%). For tighter tolerance on +3.3V rails, consider APX809S05-31SA-7 (3.08V threshold) instead.