Diodes Incorporated PT8A3233WEX

Overview

PT8A3233WEX from Pericom Semiconductor is a mixed-signal CMOS heating controller IC designed for automatic temperature regulation in 120V/240V hair curlers using external NTC sensing. It features dual-voltage auto-detection, NTC open-circuit protection, 1-hour auto-off timer (at 60Hz), direct SCR gate drive, and constant-LED indication during heating. The device operates from 3.5–5.5V supply and supports SOIC-8 packaging.

For engineers reviewing the PT8A3233WEX datasheet, PT8A3233WEX pinout, PT8A3233WEX application, or PT8A3233WEX equivalent, key selection considerations include its NTC-based 2-bit ADC input range (0.29–0.41×VDD), GATE output capable of 2.5mA sink current, 50/60Hz line-synchronized timing, and single-key ON/OFF control logic with LED feedback on Pin 5.

Technical Context

This IC integrates a 2-bit ADC for NTC voltage sampling, a clock-synchronized state machine for heating control, and digital logic to drive an SCR gate and dual LED outputs. Its internal timer counts 216,000 CLK cycles - yielding ~1.2 hours at 50Hz and ~1 hour at 60Hz - before forcing auto-off.

The device distinguishes four NTC voltage bands (VNTC0–VNTC2) to modulate SCR duty cycle and LED behavior. It implements hardware-level NTC open detection via dedicated NTC1/NTC2 pins and disables GATE output when open-circuit is detected, flashing LED2 at 1/8 CLK frequency.

Key Specifications

Pinout & Package

PT8A3233WEX is packaged in lead-free, RoHS-compliant SOIC-8 (JEDEC MS-012E/AA), with body dimensions 4.7–5.1 mm × 3.8–4.0 mm × 1.35–1.75 mm.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar heating controller applications.

Compared with PT8A3233WEX, PT8A3235WEX retains identical safety and timing functions but changes LED indication to constant-on, while PT8A3237WEX removes the auto-off timer entirely - making it unsuitable for standalone thermal safety compliance without external supervision.

Availability

PT8A3233WEX is available at Aetrix Electronics and suitable for hair curlers, flat irons, travel stylers, and hotel-grade dryers requiring stable component supply, dual-voltage support, and embedded thermal safety.

Supply support for PT8A3233WEX 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

Pericom Semiconductor (now part of Diodes Incorporated) specializes in interface, timing, and mixed-signal ICs for consumer and industrial applications, with focus on integration, reliability, and cost-effective system solutions.

PT8A3233WEX belongs to Pericom's dedicated heating controller product line, engineered specifically for contact-based thermal appliances requiring autonomous, standards-compliant temperature regulation without firmware.

FAQ

What is the function of Pin 2 (NTC2) on PT8A3233WEX?

Pin 2 (NTC2) is an open-drain output that signals NTC disconnection. When the NTC sensor opens (>20 MΩ), NTC2 pulls low and triggers LED2 to flash at 1/8 CLK frequency while disabling the GATE output - providing hardware-level fault response without software involvement.

Does PT8A3233WEX require an external crystal or RC oscillator?

No. PT8A3233WEX uses the AC mains frequency (50/60Hz) fed into the CLK pin as its sole timing reference. All internal functions - including the 1-hour auto-off timer and NTC sampling - are synchronized to this input, eliminating need for external timing components.

How does PT8A3233WEX distinguish between 120V and 240V line voltages?

The IC analyzes the amplitude of the CLK input signal derived from the AC line. Higher amplitude indicates 240V operation, prompting internal logic to reduce SCR conduction time proportionally - preventing excessive heating and ensuring consistent thermal performance across voltage regions.

Can PT8A3233WEX drive a TRIAC directly, or is an SCR mandatory?

PT8A3233WEX is designed for direct SCR gate drive only. Its GATE output delivers 2.5mA sink current at 5V - sufficient for common SCRs like MCR100-6 but insufficient for most TRIACs, which typically require ≥10mA. A buffer transistor is required for TRIAC interfacing.