Diodes Incorporated PT8A3282WEX

Overview

PT8A3282WEX from Pericom Semiconductor is a mixed-signal CMOS heating controller IC designed for dual-voltage (120V/240V) hair styling appliances. It implements proportional temperature control using an external NTC sensor, features NTC open-circuit protection, internal 5V Zener regulation, and delivers 15mA SCR gate trigger pulses. It operates across –20°C to +85°C and uses an 8-pin SOIC package.

For engineers reviewing the PT8A3282WEX datasheet, PT8A3282WEX pinout, PT8A3282WEX application, or PT8A3282WEX equivalent, key selection criteria include its 50/60Hz clock-synchronized heating timer (1.2 hr @ 50Hz), 160–240µs GATE pulse width, NTC1/NTC2 differential open-detection interface, VDD = 3.5–5.5V operation, and LED1/LED2 dual-indicator drive capability.

Technical Context

The PT8A3282WEX integrates a 5-bit ADC, on-chip controller with auto-adjusting proportional algorithm, and power-line synchronized timing logic. Its CLK input accepts 50/60Hz AC-derived signals to coordinate heating cycles and timer expiration - enabling precise 1.2-hour off-timer at 50Hz and 1-hour at 60Hz.

It supports dual-voltage operation by detecting line voltage level via CLK amplitude and adjusting output duty accordingly. The GATE pin drives SCR loads with 5mA sink current at 0.5V, while NTC2 provides active open-circuit detection feedback, and VDD is internally regulated via a 4.5–5.5V Zener.

Key Specifications

Pinout & Package

PT8A3282WEX is housed in an 8-pin lead-free and RoHS-compliant SOIC package per JEDEC MS-012E/AA, with body dimensions 4.7–5.1mm × 3.8–4.0mm × 1.35–1.75mm.

Key Features

Applications

Equivalent & Alternatives

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

Compared with PT8A3282WEX, PT8A3280WEX offers identical timing and safety features but different LED1 signaling, while PT8A3284WEX replaces SCR triggering with TRIAC-compatible output - both share the same SOIC-8 footprint and NTC interface, enabling layout reuse with minimal schematic change.

Availability

PT8A3282WEX is available at Aetrix Electronics and suitable for curling irons, flat irons, travel stylers, and low-cost heating timers requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for PT8A3282WEX 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 and industrial applications before its 2016 acquisition.

The PT8A328x series was developed specifically for cost-sensitive, safety-critical hair styling appliances - integrating analog sensing, digital timing, and power interface functions into a single 8-pin SOIC device.

FAQ

What is the maximum allowable NTC resistance for proper operation?

The PT8A3282WEX supports standard 10kΩ NTC thermistors at 25°C. Its 5-bit ADC and internal reference are calibrated for NTC resistance ranges from approximately 1kΩ to 100kΩ. Operation outside this range may cause inaccurate temperature reading or false open-detection; design validation with actual NTC curve is recommended.

Can PT8A3282WEX drive a TRIAC directly?

No - PT8A3282WEX is configured for SCR triggering only, with GATE output optimized for SCR gate characteristics (e.g., higher peak current, shorter pulse). For TRIAC control, use PT8A3284WEX or PT8A3285WEX, which provide compatible output drive strength and timing for TRIAC gate requirements.

How does the IC distinguish between 120V and 240V line operation?

The IC samples CLK input amplitude during startup: high-amplitude CLK corresponds to 240V operation and configures proportional control for higher power delivery, while low-amplitude CLK selects 120V mode with reduced duty cycle. No external resistor divider or configuration pins are needed - detection is fully automatic and hardware-based.

Is external decoupling capacitor required on VDD?

Yes - a minimum 0.1µF ceramic capacitor must be placed between VDD and GND, as close as possible to the IC. This stabilizes the internal Zener-regulated supply during GATE pulse transients and prevents brown-out during high-current LED switching events.