Diodes Incorporated PT7A7535WEX

Overview

PT7A7535WEX from Diodes Incorporated is a dual-output μP supervisor IC with precision 2.63V supply-voltage monitoring, active-high and active-low reset outputs, 200ms reset pulse width, and integrated power-fail comparator (1.25V threshold). It operates down to 1.2V V_CC and supports manual reset input with internal 250µA pull-up, used in embedded microprocessor systems requiring robust power sequencing and brownout protection.

For engineers reviewing the PT7A7535WEX datasheet, PT7A7535WEX pinout, PT7A7535WEX application, or PT7A7535WEX equivalent, key selection criteria include dual-reset polarity support, guaranteed RESET/RESET validity at V_CC = 1.2V, absence of watchdog timer (unlike PT7A751x/752x), PFI/PFO low-battery detection capability, and SOIC-8W packaging for industrial PCB layouts.

Technical Context

The PT7A7535WEX implements a precision bandgap-based voltage monitor with ±1.5% reset threshold tolerance at 2.63V nominal, and guarantees valid reset assertion during power-up, brownout, and power-down transitions. Its dual-reset architecture provides simultaneous active-low (RESET) and active-high (RESET) outputs with identical 200ms pulse timing and 1.2V minimum V_CC operation.

It integrates a dedicated 1.25V reference comparator for external power-fail detection via PFI input, driving open-drain PFO output; MR input accepts TTL/CMOS logic or mechanical switch with internal debouncing. Unlike earlier family members, PT7A7535WEX omits watchdog functionality-no WDI/WDO pins are functional, and the block diagram excludes watchdog circuitry entirely.

Key Specifications

Pinout & Package

PT7A7535WEX is housed in an 8-pin SOIC package (150mil width, JEDEC MS-012AC), with gull-wing leads, RoHS-compliant matte tin plating, and thermal pad not present. Pin 1 is marked by a beveled corner or dot.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3808G33DBVR and MAX6369KA+T, PT7A7535WEX uniquely delivers simultaneous active-high/active-low reset outputs and integrated 1.25V power-fail detection in a single SOIC-8 package-enabling simpler, more reliable power management in space-constrained industrial and medical systems without adding discrete logic or reference components.

Availability

PT7A7535WEX 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 across extended temperature ranges and long production lifecycles.

Supply support for PT7A7535WEX 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, automotive, and consumer markets.

The PT7A75xx family targets microprocessor system reliability, delivering precision voltage monitoring, reset generation, and power-fail detection in compact packages optimized for embedded control and battery-operated applications.

FAQ

What is the function of the NC pin on PT7A7535WEX?

Pin 7 is designated NC (No Connect) and is internally unconnected. It must remain electrically floating in the PCB layout; tying it to GND or V_CC is not recommended but will not damage the device. This pin exists for package compatibility within the PT7A75xx family and has no electrical role in PT7A7535WEX operation.

Can PT7A7535WEX replace PT7A7515WEX or PT7A7525WEX in an existing design?

Yes, but only if the design requires both active-high and active-low reset outputs. PT7A7535WEX replaces PT7A7515WEX (active-low only) and PT7A7525WEX (active-high only) by providing both simultaneously. However, it lacks the watchdog timer present in those variants-so replacement is valid only when watchdog functionality is unused or implemented externally.

How does the PFI/PFO circuit operate without an external reference?

The PFI input connects to an internal 1.25V precision bandgap reference. When the external voltage applied to PFI falls below this threshold, the comparator triggers and pulls PFO low. No external reference is needed-the 1.25V reference is trimmed during wafer test and specified with ±20mV tolerance across temperature, enabling accurate low-battery detection using only two external resistors.

Is PT7A7535WEX qualified for automotive applications?

PT7A7535WEX is not AEC-Q100 qualified out-of-the-box. While its SOIC-8W package is manufactured in IATF 16949-certified facilities and supports −40°C to +85°C operation, formal automotive qualification requires PPAP documentation and specific change control. Customers needing automotive-grade assurance should contact Diodes Incorporated directly for qualified variants or qualification support.