Diodes Incorporated APX812-31UG-7

Overview

APX812-31UG-7 from Diodes Incorporated is a 4-pin microprocessor supervisor IC with manual reset input and active-high push-pull RESET output, designed for precise 3.08 V supply monitoring in embedded systems. It features a fixed 200 ms power-on reset timeout, operates across –40°C to +85°C, consumes only 30–40 µA supply current, and is housed in a RoHS-compliant SOT143 package. It is used in battery-powered controllers to prevent MCU code execution during brownout.

For engineers reviewing the APX812-31UG-7 datasheet, APX812-31UG-7 pinout, APX812-31UG-7 application, or APX812-31UG-7 equivalent, key selection criteria include reset threshold accuracy (±0.05 V), MR input timing compatibility, push-pull drive capability (800 µA high-level source), and industrial temperature operation without external components.

Technical Context

The APX812-31UG-7 integrates a precision voltage reference, comparator, and 200 ms delay timer to generate a clean active-high reset signal upon V_CC rise above 3.08 V or MR assertion. Its internal circuitry ensures monotonic reset assertion and release with no chatter, even under slow-rising V_CC or noisy MR transitions.

It uses a push-pull output stage-no external pull-up required-and guarantees valid RESET logic levels down to V_CC = 1.0 V. The MR input is active-low with 100 ns minimum pulse width support and full specification over industrial temperature range.

Key Specifications

Pinout & Package

APX812-31UG-7 is packaged in a lead-free, green-compliant SOT143 (4-pin, 1.4 mm × 2.5 mm) surface-mount package with exposed pad thermal performance optimized for PCB heat dissipation (θ_JA = 240°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX809SEUR+T and TPS3808G30DBVR, APX812-31UG-7 uniquely combines fixed 200 ms timeout, guaranteed MR support, SOT143 compactness, and 30–40 µA ultra-low current-making it optimal for cost-sensitive, space-constrained industrial controllers requiring deterministic reset behavior.

Availability

APX812-31UG-7 is available at Aetrix Electronics and suitable for industrial controllers, portable medical instruments, automotive body control modules, and smart energy meters requiring stable component supply and long-term production continuity.

Supply support for APX812-31UG-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, low-power, and thermally efficient solutions for industrial, computing, and automotive markets.

The APX811/812 product line delivers precision voltage supervision with minimal external components, targeting cost-sensitive embedded systems where deterministic reset timing and wide temperature operation are critical.

FAQ

What is the exact reset threshold voltage for APX812-31UG-7?

The APX812-31UG-7 has a nominal reset threshold of 3.08 V, with a guaranteed range of 3.03 V to 3.13 V at 25°C and full specification across –40°C to +85°C. This value is laser-trimmed during production and documented in the Electrical Characteristics table of DS31960 Rev. 2.

Does APX812-31UG-7 require an external pull-up resistor on the RESET pin?

No. The APX812-31UG-7 features a push-pull output stage capable of sourcing up to 800 µA and sinking up to 3.2 mA. An external pull-up is unnecessary for standard MCU reset inputs, though a 100 kΩ pull-up is recommended only if valid RESET logic must be maintained below V_CC = 1.0 V.

Can the manual reset (MR) input be driven directly from a microcontroller GPIO?

Yes. The MR input is compatible with standard CMOS logic levels: it recognizes V_IL ≤ 0.3×V_CC as active-low and V_IH ≥ 0.7×V_CC as inactive. A 3.3 V MCU GPIO can directly assert MR without level-shifting, provided the pulse width exceeds 100 ns.

How does the 200 ms reset timeout behave during repeated brownouts?

If V_CC drops below the 3.08 V threshold again before the 200 ms timeout completes, the internal timer resets and restarts. RESET remains high (active) continuously until V_CC stays above threshold for a full 200 ms, ensuring robust immunity to ripple or intermittent supply faults.