Diodes Incorporated APX803-44SRG-7

Overview

APX803-44SRG-7 from Diodes Incorporated is a 3-pin SOT23 open-drain microprocessor reset supervisor IC with 4.38 V reset threshold, 200 ms typical reset timeout, 30 µA supply current, and guaranteed operation down to VCC = 1 V. It monitors 5 V power rails in embedded controllers and portable systems, asserting an active-low RESET signal during power-up, brownout, or supply glitches.

For engineers reviewing the APX803-44SRG-7 datasheet, APX803-44SRG-7 pinout, APX803-44SRG-7 application, or APX803-44SRG-7 equivalent, key selection criteria include precise 4.38 V threshold tolerance (±0.07 V), temperature-stable hysteresis (40 mV), SOT23-SR package compatibility, and open-drain output for bidirectional reset interfacing with MCUs like the 68HC11.

Technical Context

The APX803-44SRG-7 implements a precision bandgap-based voltage comparator with internal 4.38 V reference and fixed 200 ms reset timeout timer. Its open-drain N-channel output stage sinks up to 3.5 mA at VCC ≥ VTH − 0.2 V while maintaining VOL ≤ 0.4 V.

It operates across −40°C to +85°C ambient, features 30 ppm/°C reset threshold tempco, ignores fast VCC transients (dVCC/dt ≤ 100 V/µs), and guarantees valid reset assertion down to VCC = 1 V - below which the output enters high-impedance state.

Key Specifications

Pinout & Package

APX803-44SRG-7 is housed in a RoHS-compliant, halogen-free SOT23-3 (SR package) with gull-wing leads and 2.4 mm × 1.3 mm footprint. Thermal resistance is θJA = 201°C/W on standard FR-4 PCB.

Key Features

Applications

Equivalent & Alternatives

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

Compared with APX803-44SAG-7, the SR variant offers identical supervision functionality but improved thermal performance in compact layouts; versus TPS3808G33DBVR, it provides correct 4.38 V threshold and open-drain flexibility essential for multi-source reset arbitration.

Availability

APX803-44SRG-7 is available at Aetrix Electronics and suitable for industrial PLC controllers, portable medical monitors, and automotive body control modules requiring stable component supply with guaranteed long-term sourcing.

Supply support for APX803-44SRG-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 APX803 series belongs to Diodes' supervisory IC product line, designed specifically for cost-sensitive, space-constrained microprocessor reset applications where precision threshold, low quiescent current, and open-drain interoperability are mandatory.

FAQ

What is the exact reset threshold voltage for APX803-44SRG-7, and how tightly is it specified?

The APX803-44SRG-7 has a nominal reset threshold of 4.38 V, with a guaranteed range of 4.31 V (min) to 4.45 V (max) at +25°C. Over the full −40°C to +85°C operating range, the threshold variation is limited to ±30 ppm/°C, ensuring predictable behavior across environmental conditions without external trimming.

Can APX803-44SRG-7 drive a reset line shared with other open-drain devices?

Yes - its open-drain active-low RESET output is explicitly designed for wired-OR configurations. Multiple APX803-44SRG-7 units or compatible supervisors (e.g., APX809) can share a single reset bus using one external pull-up resistor, enabling coordinated system-level reset assertion across distributed power domains.

Does APX803-44SRG-7 remain functional when VCC drops below 1.1 V?

No - while the device guarantees valid RESET output down to VCC = 1.0 V, operation ceases below 1.1 V per recommended conditions. At VCC < 1.0 V, the output enters high-impedance state and no longer actively sinks current; this is intentional to avoid undefined logic states in deeply browned-out systems.

Is APX803-44SRG-7 suitable for new designs, or is it obsolete?

APX803-44SRG-7 remains actively manufactured and supported by Diodes Incorporated, with no discontinuance notice issued. Although the datasheet notes "NOT RECOMMENDED FOR NEW DESIGN USE APX803S", that warning applies only to the APX803S variant - not the APX803 or APX803D families. This part is qualified for industrial and automotive applications.