Diodes Incorporated PT8A3243WE

Overview

PT8A3243WE from Pericom Semiconductor is a mixed-signal CMOS LSI heating controller IC for automatic temperature regulation in 120V/240V AC-powered appliances. It integrates dual-voltage detection, 2-bit ADC-based NTC sensing, SCR gate drive, LED indicator control, and auto-shutoff timer (1h @ 60Hz). Designed specifically for hair curlers, it provides constant-LED indication during heating and disables GATE output upon NTC open-circuit fault.

For engineers reviewing the PT8A3243WE datasheet, PT8A3243WE pinout, PT8A3243WE application, or PT8A3243WE equivalent, key selection considerations include its dual-voltage operation, NTC open protection logic, 8-pin SOIC package, SCR-trigger timing behavior, and single-key heating-on/off control mode with constant LED feedback.

Technical Context

The PT8A3243WE implements a clock-synchronized, NTC-resistance–based thermal control loop using internal 2-bit ADC sampling of NTC1 voltage referenced to VDD. Its heating state transitions are governed by CLK input (50/60 Hz line frequency), ON/OFF button inputs, and internal 216,000-clock-cycle timer-yielding ~1.2 h timeout at 50 Hz and ~1 h at 60 Hz.

It features dual-mode NTC fault handling: when NTC resistance exceeds 20 MΩ, NTC2 pin outputs low and GATE is forced inactive while LED1 flashes at 1/8 CLK frequency. The GATE output is active-high, capable of directly driving an SCR gate with 2.5 mA sink current at 0.5 V.

Key Specifications

Pinout & Package

PT8A3243WE is housed in a lead-free, RoHS-compliant SOIC-8 package per JEDEC MS-012E/AA (body width 3.8–4.0 mm, length 4.7–5.1 mm, pitch 1.27 mm).

Key Features

Applications

Equivalent & Alternatives

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

Compared with PT8A3245WE and PT8A3247WE, PT8A3243WE uniquely combines constant LED indication *and* enabled 1-hour auto-off timer-making it the only variant satisfying both user-interface clarity and mandatory safety shutdown in consumer hair tools.

Availability

PT8A3243WE is available at Aetrix Electronics and suitable for hair curlers, flat irons, travel dryers, and electric blanket controllers requiring stable component supply, dual-voltage compatibility, and certified thermal safety features.

Supply support for PT8A3243WE 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) specialized in high-performance interface, timing, and mixed-signal ICs for consumer, computing, and industrial applications before its 2016 acquisition.

The PT8A324x series belongs to Pericom's dedicated heating controller product line, designed to replace discrete thermal control solutions in AC-powered personal care appliances with integrated, safety-certifiable silicon.

FAQ

What is the function of Pin 2 (NTC2) on PT8A3243WE?

Pin 2 (NTC2) is an open-drain output that pulls low when the NTC thermistor opens (R > 20 MΩ), signaling a fault condition. This action disables the GATE output and triggers LED1 to flash at 1/8 CLK frequency. It is not an input-it serves solely as a diagnostic status flag tied to NTC integrity.

Can PT8A3243WE operate with a 50 Hz AC line frequency?

Yes-PT8A3243WE accepts 50 Hz or 60 Hz CLK input. Its internal auto-off timer counts 216,000 clock cycles, resulting in ~1.2 hours timeout at 50 Hz and ~1 hour at 60 Hz. All NTC threshold voltages and GATE timing behaviors remain valid across both frequencies.

How does PT8A3243WE differ from PT8A3241WE?

PT8A3243WE uses constant LED indication during heating and has auto-off timer enabled; PT8A3241WE uses flashing LED and also enables the timer. Both use two-key control (ON/OFF separate), whereas PT8A3243WE uses single-key toggle. Their NTC thresholds, GATE drive, and pinout are identical-only LED behavior and key configuration differ.

Is an external current-limiting resistor required for the GATE output?

No-PT8A3243WE's GATE output is rated for 2.5 mA sink current at 0.5 V, sufficient to directly trigger common low-gate-threshold SCRs (e.g., BT136, TIC226) without series resistance. External limiting is unnecessary unless driving higher-threshold devices or operating beyond datasheet conditions.