Nexperia USA Inc. TLVH431NAQDBZR-QVL

Overview

TLVH431NAQDBZR-Q from Nexperia is an A-grade adjustable precision shunt regulator in SOT23 package, delivering 1.24 V reference voltage with ±1.0 % initial tolerance, 0.1 Ω dynamic cathode-anode impedance, and sink current capability from 80 µA to 70 mA across –40 °C to +125 °C. It serves as a programmable voltage reference or shunt element in automotive feedback loops, precision current sinks, and isolated SMPS regulation.

For engineers reviewing the TLVH431NAQDBZR-Q datasheet, TLVH431NAQDBZR-Q pinout, TLVH431NAQDBZR-Q application, or TLVH431NAQDBZR-Q equivalent, this device supports design of stable, AEC-Q100 grade-1 compliant voltage regulation circuits requiring tight reference accuracy, low output noise, and robust thermal performance up to +125 °C ambient.

Technical Context

The TLVH431NAQDBZR-Q implements a three-terminal shunt topology with internal bandgap reference and transconductance amplifier driving an NPN output stage. Its reference node (REF) sets output voltage via external resistor divider, while cathode (K) and anode (A) terminals define the regulated shunt path.

It operates with typical output impedance of 0.1 Ω below 1 kHz and exhibits sharp turn-on characteristics due to active output circuitry-enabling precise voltage clamping and replacing Zener diodes in high-stability applications such as automotive power supplies and isolated flyback controllers.

Key Specifications

Pinout & Package

SOT23 (TO-236AB) plastic surface-mounted package, 3-lead, standard pinning configuration (REF–K–A).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH431NAQDBZR-Q, TLVH431NQDBZR-Q trades 0.5 % reference accuracy for broader commercial availability and lower cost, while TLVH431NAIDBZR-Q retains A-grade tolerance but sacrifices 40 °C of upper-temperature margin-making TLVH431NAQDBZR-Q optimal for high-reliability under-hood applications needing both precision and extended thermal range.

Availability

TLVH431NAQDBZR-Q is available at Aetrix Electronics and suitable for automotive power management, isolated SMPS feedback, and precision current regulation requiring stable component supply across extended temperature operation.

Supply support for TLVH431NAQDBZR-Q 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

Nexperia is a global semiconductor expert focused on high-volume, high-reliability logic, discrete, and MOSFET devices, with deep expertise in automotive-qualified components.

The TLVH431N-Q family targets automotive and industrial systems requiring AEC-Q100-compliant, adjustable shunt regulation-designed specifically for feedback stability, thermal resilience, and long-term parametric consistency in harsh environments.

FAQ

What is the minimum cathode current required for regulation?

The TLVH431NAQDBZR-Q requires a minimum cathode current (IK(min)) of 55 µA to maintain regulation, verified at VKA = Vref across its full operating temperature range. Below this threshold, the device exits regulation and behaves as an open circuit at the cathode, making it critical to size the external resistor network to guarantee ≥80 µA worst-case current under all conditions including low-temperature and low-VKA scenarios.

How does the mirrored vs. normal pinning affect PCB layout?

TLVH431NAQDBZR-Q uses normal pinning (REF–K–A), matching standard SOT23 footprint orientation. Mirrored variants (e.g., those ending in MQDBZR-Q) swap REF and K pins-using them interchangeably causes immediate functional failure. Layouts must strictly follow the "normal" pinout: Pin 1 = REF, Pin 2 = K, Pin 3 = A-and verify land pattern alignment against Figure 29 in the Nexperia datasheet to prevent solder bridging or misalignment.

Can TLVH431NAQDBZR-Q replace a Zener diode directly?

Yes-TLVH431NAQDBZR-Q replaces Zener diodes in shunt regulation roles with superior performance: sharper knee, lower dynamic impedance (0.1 Ω vs. typical Zener's >10 Ω), and programmable voltage (1.24–14 V). However, unlike passive Zeners, it requires a minimum 0.19 µA reference current and cannot operate with REF left floating; the external resistor divider must always be connected to establish bias and regulation.

What thermal derating applies at +125 °C ambient?

At Tamb = +125 °C, the maximum allowable power dissipation drops to 350 mW on standard FR4 PCB (single-sided copper, tin-plated, standard footprint), per Figure 2 curve (1). This corresponds to ~50 mA at 7 V VKA or ~25 mA at 14 V VKA. Designers must calculate worst-case power (VKA × IK) and apply derating early in layout-especially in sealed enclosures-using ceramic PCB mounting (curve 3) if >580 mW is needed.