Diodes Incorporated APX803S05-46SA-7

Overview

APX803S05-46SA-7 from Diodes Incorporated is a 3-pin SOT23 microprocessor reset supervisor IC with 4.63 V reset threshold, open-drain active-low RESET output, 50 ms typical reset timeout, 10 µA supply current, and guaranteed operation down to VCC = 1 V. It monitors 5.0 V power rails in embedded microcontroller systems to prevent erroneous code execution during power-up, brownout, or supply glitches.

For engineers reviewing the APX803S05-46SA-7 datasheet, APX803S05-46SA-7 pinout, APX803S05-46SA-7 application, or APX803S05-46SA-7 equivalent, key selection criteria include reset threshold accuracy (±0.07 V), temperature coefficient (30 ppm/°C), open-drain drive capability (3.5 mA sink at 0.4 V), and compatibility with bidirectional µP reset pins requiring external pull-up.

Technical Context

The APX803S05-46SA-7 implements a precision bandgap-based voltage comparator with hysteresis to detect VCC drops below 4.63 V, triggering an open-drain RESET signal that remains asserted for ≥20 ms and ≤70 ms after VCC recovers above threshold. Its internal timer ensures deterministic reset hold time independent of external RC networks.

Designed for low-power systems, it draws only 10 µA typical supply current and guarantees valid logic-low RESET output down to VCC = 1 V; below 1 V, the output enters high-impedance state. The device ignores fast transients on VCC (dVCC/dt up to 100 V/µs) and supports interfacing with multiple supply domains via level-shifted reset assertion.

Key Specifications

Pinout & Package

APX803S05-46SA-7 is housed in a RoHS-compliant, halogen-free SOT23-3 (SA) package with 2.9 mm × 1.3 mm footprint and 0.95 mm height. Thermal resistance is θJA = 232 °C/W, suitable for PCBs with minimal copper pour.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX809SEUR+T and TPS3808G33DBVR, the APX803S05-46SA-7 uniquely combines 4.63 V precision threshold, 50 ms optimized timeout, open-drain flexibility, and 10 µA ICC - making it ideal for 5.0 V µP systems needing responsive yet robust reset control without external components.

Availability

APX803S05-46SA-7 is available at Aetrix Electronics and suitable for industrial PLC controllers, portable medical monitors, automotive body control modules, and smart energy meters requiring stable component supply, precise 5.0 V rail supervision, and long-term lifecycle support.

Supply support for APX803S05-46SA-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' supervisory IC product line, designed specifically for cost-sensitive, space-constrained microprocessor reset applications requiring precision voltage monitoring, low quiescent current, and robust transient immunity.

FAQ

What is the exact reset threshold voltage and its tolerance for APX803S05-46SA-7?

The APX803S05-46SA-7 has a nominal reset threshold of 4.63 V, with a guaranteed range of 4.56 V to 4.70 V at +25°C. Over the full –40°C to +85°C operating temperature range, the threshold drift is limited to ±0.07 V, corresponding to a temperature coefficient of 30 ppm/°C as specified in the DS39161 datasheet.

Does APX803S05-46SA-7 require an external pull-up resistor on the RESET pin?

Yes - the RESET pin is open-drain active-low and requires an external pull-up resistor to a valid logic-high voltage (typically the same 5.0 V rail being monitored or another compatible supply). Diodes recommends values between 10 kΩ and 100 kΩ depending on bus capacitance and sink current requirements; 47 kΩ is commonly used for 3.5 mA sink capability at 0.4 V output low.

Can APX803S05-46SA-7 operate reliably when VCC drops below 2.0 V?

Yes - the device guarantees valid RESET output down to VCC = 1.0 V. Below 1.0 V, the internal circuitry ceases to function and the RESET pin transitions to high-impedance; however, this condition coincides with µP nonoperation, so no functional conflict arises. The 10 µA supply current remains stable down to 1.0 V per electrical characteristics table.

How does the 50 ms reset timeout differ from the standard APX803S-XX variant's 240 ms timeout?

The "05" suffix denotes a factory-trimmed internal timer delivering 50 ms typical timeout (20–70 ms min/max), optimized for faster-recovering systems like portable devices or real-time controllers. In contrast, the base APX803S-XX (no suffix) provides 240 ms typical (140–280 ms), intended for legacy µPs with longer initialization sequences. Both share identical threshold, accuracy, and quiescent current specifications.