Toshiba Semiconductor and Storage TLP171D(TP,F

Overview

TLP171D(TP,F) from Toshiba Electronic Devices & Storage Corporation is a normally-open photorelay IC comprising an infrared LED optically coupled to a photo-MOSFET output stage. It delivers 200 V OFF-state voltage, 200 mA ON-state current, and 8 Ω max ON-resistance in a compact SOP-4 package with 2.54 mm pitch - enabling solid-state replacement of mechanical relays in low-power signal switching applications such as PBX line interface cards and security system I/O modules.

For engineers reviewing the TLP171D(TP,F) datasheet, TLP171D(TP,F) pinout, TLP171D(TP,F) application, or TLP171D(TP,F) equivalent, key selection criteria include verified trigger LED current (≤0.2 mA for t >1 s), isolation voltage (1500 Vrms), and dual-drain output configuration suitable for single-pole, single-throw (1-Form-A) AC/DC load control without external snubbers.

Technical Context

The TLP171D(TP,F) implements optical isolation between input and output stages using GaAs infrared LED excitation of a silicon photo-MOSFET. Its internal structure treats Pins 1–2 as a single anode–cathode pair and Pins 3–4 as paralleled drain terminals - forming a two-terminal output device with inherent bidirectional blocking capability up to 200 V.

It operates with low drive power: only 0.2 mA LED forward current sustains conduction at ambient temperatures above 1 s, while maintaining <1 nA OFF-state leakage at rated VOFF. Switching times are specified at 1–10 ms range under 20 V supply and 200 Ω load, supporting moderate-speed digital I/O and analog signal routing where galvanic separation is mandatory.

Key Specifications

Pinout & Package

Package: SOP-4 (Toshiba designation 11-5H1S), surface-mount, 2.54 mm lead pitch, 2.1 mm profile, 0.1 g typical weight.

Key Features

Applications

Equivalent & Alternatives

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

Compared with PVG612A and PS8501-AX, the TLP171D(TP,F) offers the lowest trigger current (0.2 mA) and tightest R_ON (8 Ω) in SOP-4, making it optimal for battery-powered or low-noise analog signal routing where minimal drive power and voltage drop are critical.

Availability

TLP171D(TP,F) is available at Aetrix Electronics and suitable for security system I/O modules, modem/fax PC cards, and measuring instruments requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for TLP171D(TP,F) 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

Toshiba Electronic Devices & Storage Corporation designs and manufactures discrete semiconductors, power devices, and optoelectronics for industrial, consumer, and communications markets.

The TLP171D(TP,F) belongs to Toshiba's photorelay product line, engineered specifically for mechanical relay replacement in space-constrained, low-power, and high-reliability signal switching applications.

FAQ

What is the maximum continuous ON-state current rating for the TLP171D(TP,F)?

The TLP171D(TP,F) supports a maximum continuous ON-state current of 200 mA at Ta ≤ 25 °C. Derating applies linearly at −2.0 mA/°C above 25 °C, limiting usable current to approximately 160 mA at 45 °C ambient. This rating assumes proper PCB copper area for thermal dissipation and accounts for the device's 8 Ω max R_ON to ensure junction temperature remains within 125 °C limit. The TLP171D(TP,F) is not rated for pulsed currents exceeding 600 mA.

Does the TLP171D(TP,F) support AC load switching?

Yes, the TLP171D(TP,F) supports bidirectional AC load switching due to its MOSFET-based output structure and 200 V minimum OFF-state voltage rating. Its symmetrical drain terminals (Pins 3 and 4) allow connection across either polarity of an AC waveform, provided peak voltage remains below 200 V. The TLP171D(TP,F) exhibits <1 nA OFF-state leakage at rated V_OFF, ensuring reliable zero-crossing detection and minimal power loss during AC idle periods.

What is the recommended LED forward current for reliable turn-on of the TLP171D(TP,F)?

Toshiba specifies a maximum trigger LED current of 0.2 mA for sustained conduction (t >1 s) and 0.1 mA for short pulses (t ≤1 s). A design target of 0.5 mA provides robust margin against aging and temperature drift while staying well within the 30 mA absolute maximum rating. The TLP171D(TP,F)'s low I_FT enables direct drive from most microcontroller GPIOs using a simple 10 kΩ series resistor from 5 V or 6.8 kΩ from 3.3 V.

How is isolation performance validated for the TLP171D(TP,F)?

The TLP171D(TP,F) is UL-recognized per UL 1577 (File No. E67349) and cUL-recognized per CSA Component Acceptance Service (File No. E67349), with minimum isolation voltage of 1500 Vrms tested for 60 seconds. Its isolation resistance exceeds 5 × 10¹⁰ Ω and input-to-output capacitance is limited to 0.8 pF typical - verified via factory production testing per Toshiba's quality protocol. These values are guaranteed across the full operating temperature range (−40 to +85 °C) and apply to the TLP171D(TP,F) in its final packaged form.

Can the TLP171D(TP,F) replace mechanical relays in PBX line interface circuits?

Yes, the TLP171D(TP,F) is explicitly qualified for Private Branch Exchange (PBX) applications per Toshiba's datasheet. Its 200 V OFF-state voltage safely handles POTS line ringing voltages (typically 90 V RMS, ~127 V peak), while its <1 nA OFF-state leakage prevents false ring detection. With 3.5 ms typical turn-on time and no contact wear, the TLP171D(TP,F) delivers >10⁸ operations versus ~10⁵ for equivalent mechanical relays - making it ideal for high-cycle PBX line seizure and status reporting functions.