Diodes Incorporated PT8A3286WE

Overview

PT8A3286WE from Pericom Semiconductor is a mixed-signal CMOS heating controller IC designed for 120V/240V AC-powered thermal appliances. It implements proportional temperature control using an external NTC sensor, features NTC open-circuit protection, auto power-off after 1.15–1.25 hour timer timeout (50/60 Hz CLK), and drives TRIACs with 160–240 µs trigger pulses up to 15 mA. Used in hair straighteners and curling irons.

For engineers reviewing the PT8A3286WE datasheet, PT8A3286WE pinout, PT8A3286WE application, or PT8A3286WE equivalent, key selection criteria include TRIAC-compatible gate drive timing, dual-voltage line sensing via CLK input, NTC open-detection logic on NTC1/NTC2, LED2 flash mode behavior, and SOIC-8 thermal/power dissipation limits (500 mW).

Technical Context

The PT8A3286WE integrates a 5-bit ADC for NTC voltage sampling, internal Zener regulation (4.5–5.5 V), and a clock-synchronized state machine that toggles GATE output based on NTC voltage thresholds relative to VADC_BIT1 and VADC_BIT14. Its heating-on state activates proportional control only when CLK frequency is detected at 50/60 Hz and NTC1 input remains within valid range.

NTC2 serves as an open-detection output-pulled low during NTC disconnection-while GATE delivers timed pulses synchronized to CLK zero-crossing. The device enters automatic OFF state after 216,000 clock cycles (≈1.2 hr @60 Hz), independent of external microcontroller intervention.

Key Specifications

Pinout & Package

PT8A3286WE is housed in a lead-free, RoHS-compliant 8-pin SOIC package (JEDEC MS-012E/AA), with body dimensions 4.7–5.1 mm × 3.8–4.0 mm × 1.35–1.75 mm and 1.27 mm pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with PT8A3284WE and PT8A3285WE, PT8A3286WE uniquely combines flash-mode LED1 with non-timer LED2 - enabling distinct visual states for power-on, heating, and fault without external logic.

Availability

PT8A3286WE is available at Aetrix Electronics and suitable for hair styling tools, electric blanket controllers, beauty device heater modules, and other thermally regulated consumer appliances requiring stable component supply and long-lifecycle support.

Supply support for PT8A3286WE 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 power management ICs for consumer and industrial markets before its 2016 acquisition.

The PT8A328x series was developed specifically for cost-sensitive, self-contained thermal control in AC-powered personal care appliances - emphasizing integration, safety compliance, and minimal external component count.

FAQ

What is the function of the NTC2 pin on PT8A3286WE?

NTC2 is an open-drain digital output that pulls low when the NTC sensor is disconnected or open-circuited. This signal can be monitored by an external microcontroller or used to disable downstream power stages. It operates independently of software and responds within one CLK cycle, providing hardware-level fault detection without delay.

Does PT8A3286WE require an external crystal or clock source?

No - PT8A3286WE uses the AC mains frequency as its timing reference via the CLK pin. It accepts 50 Hz or 60 Hz sinusoidal or rectified input directly from the power line, eliminating need for crystals, oscillators, or timing resistors. Internal circuitry automatically detects frequency to configure voltage mode and timer scaling.

Can PT8A3286WE drive a 400 V TRIAC directly?

Yes - PT8A3286WE's GATE pin delivers 160–240 µs pulses with ≥5 mA sink capability at 0.5 V, sufficient to trigger standard 400 V TRIACs (e.g., BT136, TYN1025) when used with appropriate gate resistor (typically 100–470 Ω). No external driver transistor is required for TRIACs rated ≤25 A RMS.

How does the heating timer behave if power is interrupted and restored?

The internal heating timer resets on every power-on event. If AC power is cycled (e.g., unplugged and reinserted), the 1.15–1.25 hour countdown restarts from zero. There is no non-volatile memory or battery-backed retention - ensuring fail-safe behavior where heating cannot resume mid-cycle after interruption.