Diodes Incorporated APX803S05-29SR-7

Overview

APX803S05-29SR-7 from Diodes Incorporated is a 3-pin SOT23 open-drain microprocessor reset supervisor IC designed for 2.93 V supply monitoring in embedded systems. It asserts an active-low RESET signal during power-up, brownout, or voltage drop below threshold and holds it for 50 ms (typ.) after VCC recovers. Features guaranteed operation down to VCC = 1 V, 10 µA typical supply current, and ±30 ppm/°C reset threshold tempco - ideal for battery-powered controllers and portable instrumentation.

For engineers reviewing the APX803S05-29SR-7 datasheet, APX803S05-29SR-7 pinout, APX803S05-29SR-7 application, or APX803S05-29SR-7 equivalent, key selection criteria include reset timeout duration (50 ms typ.), precise 2.93 V threshold with tight tolerance (2.89–2.97 V), open-drain output compatibility with bidirectional µP reset pins, and guaranteed reset validity at VCC ≥ 1 V.

Technical Context

The APX803S05-29SR-7 implements a precision voltage comparator with hysteresis-free threshold detection at 2.93 V (min 2.89 V, max 2.97 V) and a fixed internal timer that generates a 50 ms (typ.) active-low reset pulse after VCC rises above threshold. Its open-drain output requires an external pull-up and supports level-shifting across supply domains.

It operates over –40°C to +85°C, draws only 10 µA (typ.) supply current, and guarantees valid reset assertion down to VCC = 1 V. The device ignores fast transients on VCC and maintains correct logic state without external components - eliminating trimming resistors or capacitors required by discrete reset solutions.

Key Specifications

Pinout & Package

SOT23-3 (SR package) surface-mount package with 2.9 mm × 1.3 mm footprint, 0.95 mm height, and gull-wing leads. RoHS-compliant, halogen-free, lead-free construction.

Key Features

Applications

Equivalent & Alternatives

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

Compared with APX803S05-29SA-7, the SR variant offers identical performance with industry-standard SOT23 pin mapping - simplifying layout reuse. Versus MAX809SEUR+T, the APX803S05-29SR-7 provides shorter, more responsive reset timing and open-drain flexibility essential for multi-device reset buses.

Availability

APX803S05-29SR-7 is available at Aetrix Electronics and suitable for industrial PLC controllers, portable medical monitors, smart energy meters, and automotive body control modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for APX803S05-29SR-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 integrated circuits, specializing in high-reliability power management, signal integrity, and protection solutions for industrial, computing, and consumer markets.

The APX803S series belongs to Diodes' precision voltage supervisor product line, engineered specifically for cost-sensitive, space-constrained microprocessor reset applications where accuracy, low power, and guaranteed operation down to 1 V are mandatory.

FAQ

What is the exact reset threshold voltage for APX803S05-29SR-7?

The APX803S05-29SR-7 has a nominal reset threshold of 2.93 V, with a guaranteed range of 2.89 V (min) to 2.97 V (max) at +25°C. This value is specified in the Electrical Characteristics table of DS39161 Rev. 2–2, and its temperature coefficient is ±30 ppm/°C over –40°C to +85°C.

Does APX803S05-29SR-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 (e.g., same VCC or another supply). Typical values range from 10 kΩ to 100 kΩ depending on bus capacitance and sink current requirements; Diodes recommends verifying rise time against µP input specifications.

Can APX803S05-29SR-7 operate reliably below 2.5 V supply voltage?

Yes - the device is fully functional down to VCC = 1.0 V, with guaranteed reset assertion and correct logic state. At VCC < 1.0 V, the RESET output becomes high-impedance, but this occurs only after system operation has already ceased, making it safe for brownout detection in low-voltage systems.

How does the 50 ms reset timeout differ from the 240 ms version in the APX803S family?

The APX803S05-29SR-7 delivers a 50 ms (typ.) reset pulse, optimized for faster-booting microcontrollers like ARM Cortex-M0/M3. In contrast, the standard APX803S-29SR-7 provides 240 ms (typ.), intended for legacy 8-bit µPs requiring longer initialization. Both share identical threshold, tempco, and supply current specs.