Toshiba Semiconductor and Storage TCTH012BE,LF(CT

Overview

TCTH012BE,LF(CT from Toshiba Electronic Devices & Storage Corporation is a CMOS over-temperature detection IC that monitors external PTC thermistors and outputs an open-drain FLAG signal upon threshold exceedance. It delivers 1 μA (Typ.) constant-current drive to the PTC, consumes only 1.8 μA (Typ.) total supply current, and features latch functionality triggered by temperature rise - used in notebook PCs, industrial equipment, and home appliances for thermal safety shutdown.

For engineers reviewing the TCTH012BE,LF(CT) datasheet, TCTH012BE,LF(CT) pinout, TCTH012BE,LF(CT) application, or TCTH012BE,LF(CT) equivalent, this page provides verified functional identity, confirmed latch behavior with RESET release, open-drain output logic, ESV package dimensions, and real-world PTC thermistor interface constraints - all critical for thermal protection circuit design and BOM validation.

Technical Context

The TCTH012BE,LF(CT) implements a precision voltage comparator architecture sensing PTCO terminal voltage against a fixed 0.50 V (Typ.) detect threshold (VDET) with 0.1 V hysteresis. Its internal constant-current source (IPTCO = 1.00 μA ±8% at VDD = 3.3 V) establishes temperature setpoint via external PTC resistance selection.

It operates across -40 °C to +125 °C with supply voltage range 1.7–5.5 V, includes UVLO (1.5 V) and 20 μs operation mask time, and uses a dedicated RESET pin to release latched PTCGOOD output - distinguishing it from non-latch variants like TCTH011BE,LF(CT).

Key Specifications

Pinout & Package

Package: ESV (SOT-553), 1.6 mm × 1.6 mm × 0.55 mm, weight 2.98 mg (Typ.).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar over-temperature detection applications.

Compared with TCTH012BE,LF(CT), the TCTH012AE,LF(CT) simplifies interface design but sacrifices voltage-level flexibility, while the MAX6505EUT+T lacks latch capability entirely - making TCTH012BE,LF(CT) uniquely suited for safety-critical applications requiring guaranteed fault persistence without added components.

Availability

TCTH012BE,LF(CT) is available at Aetrix Electronics and suitable for notebook PC thermal management, industrial motor drive protection, smart home appliance safety cutoff, and medical power supply thermal guard applications requiring stable component supply and long-term lifecycle support.

Supply support for TCTH012BE,LF(CT) 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 high-reliability analog and power semiconductors for industrial, automotive, and consumer applications.

The TCTH0xxxE series targets compact, ultra-low-power thermal safety monitoring - delivering latch-enabled over-temperature detection with minimal PCB footprint and sub-2 μA supply current for embedded systems where thermal integrity is mission-critical.

FAQ

What is the primary function of the TCTH012BE,LF(CT)?

The TCTH012BE,LF(CT) is a CMOS over-temperature detection IC that senses rising temperature via an external PTC thermistor and asserts a latched open-drain FLAG signal (PTCGOOD) when the thermistor's resistance crosses a voltage threshold determined by its 1.00 μA (Typ.) constant-current source. It is designed for fail-safe thermal shutdown in space-constrained, low-power systems.

Does the TCTH012BE,LF(CT) require an external pull-up resistor on PTCGOOD?

Yes, the TCTH012BE,LF(CT) features an open-drain PTCGOOD output and requires an external pull-up resistor to the desired logic rail (e.g., 1.8 V, 3.3 V, or 5 V). This configuration enables voltage-level translation and shared-bus operation - a key distinction from push-pull variants like TCTH012AE,LF(CT).

How does the latch function work in the TCTH012BE,LF(CT)?

The TCTH012BE,LF(CT) latches the PTCGOOD output low upon over-temperature detection and maintains that state until the RESET pin is driven high (≥0.84 V) or VDD is cycled. This ensures fault persistence across brief power interruptions or MCU resets - critical for safety compliance in industrial and medical applications.

What is the recommended PTC thermistor resistance range for use with the TCTH012BE,LF(CT)?

For a single PTC thermistor at 25 °C, Toshiba recommends 17.8 kΩ to 27 kΩ (α = 50, β = 10) or 9.1 kΩ to 27 kΩ (α = 100, β = 10), based on VDET = 0.50 V (Typ.) and IPTCO = 1.00 μA (Typ.). Exact values depend on target trip temperature and PTC resistance-vs.-temperature curve - refer to Section 10.3.1 of the TCTH0xxxE datasheet.

Can multiple PTC thermistors be connected to the TCTH012BE,LF(CT)?

Yes, up to ~30 PTC thermistors may be connected in series to the PTCO pin, provided they share identical 25 °C resistance values. The effective resistance window scales with quantity (N): for N = 10 and α = 180, use 4.7 kΩ–9.4 kΩ. Mismatched thermistors cause inaccurate trip points - design must account for combined resistance shift during simultaneous overheating.