Texas Instruments TL432CDBZR

Overview

TL432CDBZR from Texas Instruments is a precision programmable shunt voltage reference in SOT-23-3 package, featuring 0.5% initial reference voltage tolerance at 25°C, 2.495 V nominal Vref, and operation from 0°C to 70°C. It delivers 1 mA to 100 mA sink current with 0.2 Ω typical dynamic impedance and supports adjustable output from Vref to 36 V-used in feedback loops of AC/DC converters and notebook power adapters.

For engineers reviewing the TL432CDBZR datasheet, TL432CDBZR pinout, TL432CDBZR application, or TL432CDBZR equivalent, key selection criteria include its C-grade temperature range (0°C to 70°C), B-grade accuracy (0.5%), SOT-23-3 pinout distinct from TL431, low output noise, and sharp turn-on characteristic for Zener replacement in regulated power supplies.

Technical Context

The TL432CDBZR implements a three-terminal adjustable shunt regulator architecture with an internal error amplifier, reference, and NPN pass transistor. Its REF pin senses voltage relative to ANODE, enabling precise feedback control when paired with two external resistors-no external compensation required in most configurations.

Unlike the TL431, the TL432CDBZR uses a reversed pinout in SOT-23-3: Pin 1 = CATHODE, Pin 2 = REF, Pin 3 = ANODE. This variant maintains identical electrical specifications-including 6 mV max reference voltage drift over 0°C–70°C-but requires PCB layout adaptation for drop-in replacement.

Key Specifications

Pinout & Package

SOT-23-3 package (2.90 mm × 1.30 mm), surface-mount, lead-free, RoHS-compliant. Thermal resistance R_θJA = 206°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TL431CDBZR and TLVH431ACDBVR, TL432CDBZR offers the same B-grade accuracy and C-temp rating but with a unique SOT-23-3 pinout optimized for new designs prioritizing layout flexibility and Zener-replacement simplicity in mid-range voltage applications.

Availability

TL432CDBZR is available at Aetrix Electronics and suitable for rack server power, notebook PC power adapter design, and industrial AC/DC converters requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for TL432CDBZR 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

Texas Instruments is a global semiconductor leader delivering analog, embedded processing, and connectivity solutions with emphasis on reliability, performance, and broad application coverage.

The TL43x family was designed as precision programmable shunt references to replace Zener diodes in feedback networks of switching and linear regulators-targeting cost-sensitive, high-volume power management applications across computing and industrial markets.

FAQ

What is the reference voltage tolerance of TL432CDBZR at 25°C?

The TL432CDBZR has a reference voltage tolerance of ±0.5% at 25°C (B grade). This is confirmed in Section 6.11 of the TI datasheet SLVS543S, where TL432BC electrical characteristics specify Vref min/max as 2483 mV / 2507 mV at 10 mA cathode current-centered on 2495 mV. This tight tolerance enables high-accuracy regulation without calibration in commercial power supplies.

How does TL432CDBZR differ from TL431CDBZR in pin configuration?

The TL432CDBZR uses a reversed SOT-23-3 pinout versus TL431CDBZR: TL432CDBZR Pin 1 = CATHODE, Pin 2 = REF, Pin 3 = ANODE; TL431CDBZR Pin 1 = REF, Pin 2 = ANODE, Pin 3 = CATHODE. Both share identical electrical specs, but TL432CDBZR's pinout avoids ANODE-to-ground short risk in certain feedback topologies and requires layout change for substitution.

What is the operating temperature range for TL432CDBZR?

The TL432CDBZR is rated for operation from 0°C to 70°C (C grade), as defined in the device nomenclature and verified in Section 6.4 of the datasheet. This range applies specifically to the "C" suffix and distinguishes it from I-grade (−40°C to 85°C) and Q-grade (−40°C to 125°C) variants-making TL432CDBZR ideal for commercial indoor power applications.

Can TL432CDBZR replace a Zener diode in voltage regulation circuits?

Yes, TL432CDBZR is explicitly designed as a superior Zener diode replacement. Its active circuitry provides sharp turn-on, low dynamic impedance (0.2 Ω), and adjustable output (2.495 V to 36 V) with far better temperature stability (≤6 mV drift over 0°C–70°C) than standard Zeners. It requires only two external resistors-no additional transistors or compensation-reducing component count and improving accuracy in on-board regulation.

What is the maximum cathode current supported by TL432CDBZR?

The TL432CDBZR supports continuous cathode current from 1 mA to 100 mA, per Section 6.4 Recommended Operating Conditions and Section 6.1 Absolute Maximum Ratings (IKA = −100 mA to +150 mA). At 100 mA, power dissipation remains within safe limits in SOT-23-3 at TA ≤ 70°C, enabling direct drive of optocoupler LEDs in isolated SMPS feedback paths without external buffering.