ATL432LIBIDBZR - 2.5V Adjustable Shunt Reference, ±0.5%, SOT-23-3 | Texas Instruments
MPN： ATL432LIBIDBZR ✓ 啟用中ATL432LIBIDBZR 概覽
A shunt voltage reference is a two-terminal device that maintains a constant voltage between its cathode and anode by sinking or sourcing current, behaving like a precision Zener diode with a programmable breakdown voltage. It belongs to the broader category of voltage references -> linear regulators -> power management ICs -> analog semiconductors, and is widely used to set the threshold for op-amps, comparators, ADC/DAC references, and adjustable linear regulators.
Key features include a low minimum cathode current of approximately 100 A (typical), a wide programmable output range of 2.5 V to 36 V set by an external resistor divider, and a typical output impedance around 0.05 ohm at low frequencies. The reference exhibits excellent stability across load and temperature variations, with a typical temperature drift in the tens of ppm/C range, making it well suited to systems that previously relied on a TL431/TL432 but require tighter initial accuracy and lower quiescent current.
The ATL432 uses a bandgap reference core with a bipolar process technology. The DBZ (SOT-23-3) package is pin-compatible with the industry-standard TL431/TL432 footprint but with an inverted pinout, where the reference terminal is pin 2 instead of pin 1. The device is qualified across the -40C to +125C operating range and is offered in tape and reel packaging for high-volume manufacturing.
Typical applications include secondary-side regulation in isolated DC-DC converters, adjustable precision voltage monitoring, precision current limiting, threshold detection in comparators, and low-power analog bias generation in battery-powered IoT and portable industrial equipment.
When designing with the ATL432LIBIDBZR, ensure the cathode current stays within the minimum/maximum limits under all operating conditions and place the device close to the load to minimize parasitic resistance.
This page synthesizes TI datasheet parameters, distributor pricing, and practical design notes into a single reference not found in the manufacturer datasheet alone.
直接替換替代品，適用於 ATL432LIBIDBZR — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： ATL432LIBIDBZR （相同外形與佔位） — 差異在於 Operating Temperature Range, Package, Reference Type.
ATL432LIAIDBZR
✅ 直接替換📋 參考替代品（不在目錄中）
ATL432LIBIDBZRQ1
✅ 直接替換📋 參考替代品（不在目錄中）
TL432LIBIDBZR
✅ 直接替換📋 參考替代品（不在目錄中）
TL431LIBIDBZR
✅ 直接替換📋 參考替代品（不在目錄中）
ATL432LIBQDBZR
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
ATL432LIBIDBZR 規格
| Reference Type | Shunt, Adjustable |
| Reference Voltage (Vref) | 2.5 V |
| 輸出電壓範圍 | 2.5 V to 36 V |
| Initial Accuracy (B grade) | ±0.5% (at 25C) |
| Cathode Current (max) | 100 mA |
| Minimum Cathode Current (Imin) | 0.1 mA (typical, low-Iq) |
| Output Impedance | 0.05 ohm (typical at low frequency) |
| 工作溫度範圍 | -40C to +125C |
| 封裝 | SOT-23-3 (DBZ) |
| 腳位數 | 3 |
| 安裝類型 | Surface Mount |
| Tape and Reel Quantity | 3000 |
| RoHS 狀態 | Compliant |
| Lead-Free | Yes |
| Pinout | Pin 1: Cathode, Pin 2: Reference, Pin 3: Anode (DBZ, inverted vs TL432) |
ATL432LIBIDBZR 腳位配置
| 腳位 1 | CATHODE — Cathode (K) - shunt current flows into this pin |
| 腳位 2 | REFERENCE — Reference (REF) - resistor divider sets Vka to 2.5 V x (1+R1/R2) |
| 腳位 3 | ANODE — Anode (A) - ground reference for the shunt regulator |
典型應用
ATL432LIBIDBZR 適用於 7 應用s: Isolated DC-DC Converter Secondary-Side Reference, Adjustable Precision Voltage Monitor, Precision Current Limiting / Constant-Current Sink, Comparator Threshold Detection, Adjustable Linear Regulator Reference, Battery-Powered IoT Sensor Bias, Power-Supply Over-Voltage Protection.
Isolated DC-DC Converter Secondary-Side Reference
The ATL432LIBIDBZR generates a precision 2.5 V reference on the secondary side of an isolated DC-DC converter, where the TL431-style architecture drives an optocoupler to close the primary-side regulation loop. Its adjustable cathode voltage up to 36 V allows the same part to set primary-side feedback at 3.3 V, 5 V, 12 V, or 15 V outputs by changing the resistor divider. The low minimum cathode current (~100 uA typical) keeps quiescent loss minimal in light-load standby, improving overall converter efficiency at no-load conditions.
推薦
Adjustable Precision Voltage Monitor
The ATL432LIBIDBZR serves as the threshold-setting element in adjustable voltage monitoring circuits, where it drives a comparator or directly toggles a logic output when an input rail drifts outside its programmed window. The 2.5 V reference and external resistor network allow thresholds anywhere between 2.5 V and 36 V, so the same part can supervise 3.3 V, 5 V, 12 V, or 24 V rails. Its low-Iq cathode current suits portable battery systems that require always-active monitoring.
推薦
Precision Current Limiting / Constant-Current Sink
The ATL432LIBIDBZR functions as the precision shunt regulator in a constant-current sink or programmable current-limit circuit. Combined with a sense resistor between its cathode and reference pins, it forces a stable current load for LED driving, battery test, or precision current-mirror biasing. The 2.5 V reference multiplied by the sense-resistor value determines the load current, and the same DBZ SOT-23 footprint enables compact constant-current modules.
推薦
Comparator Threshold Detection
The ATL432LIBIDBZR provides a stable reference for comparator threshold detection in over-voltage, under-voltage, and window-comparator circuits. The 2.5 V reference combined with a resistor divider sets the comparator trip point, and the reference's low temperature drift maintains trip accuracy across the -40C to +125C operating range. Industrial control, battery management, and motor-drive fault circuits benefit from this stable, low-Iq reference.
推薦
Adjustable Linear Regulator Reference
The ATL432LIBIDBZR replaces a fixed reference IC to create an adjustable-output LDO when its reference voltage and resistor network set the feedback point. By tying the divider to a linear regulator's feedback node, designers achieve a programmable output that tracks the precision of the ATL432's 2.5 V bandgap reference. The low-Iq operation also keeps overall LDO quiescent current low, supporting portable and battery-powered designs.
推薦
Battery-Powered IoT Sensor Bias
The ATL432LIBIDBZR supplies a precision bias voltage to low-power analog front ends, op-amps, and sensor excitation circuits in battery-powered IoT nodes. The 2.5 V reference combined with the low minimum cathode current (~100 uA typical) keeps quiescent draw minimal while delivering a reference more accurate than typical LDO outputs. The compact SOT-23-3 (DBZ) footprint fits space-constrained wearable designs.
推薦
Power-Supply Over-Voltage Protection
The ATL432LIBIDBZR drives an OVP crowbar or load-disconnect circuit when a downstream rail exceeds its programmed threshold. The 2.5 V reference multiplied by the resistor divider allows the OVP trip to track 3.3 V, 5 V, 12 V, or 24 V rails. The 100 mA maximum cathode current is sufficient to drive medium-power SCR crowbars or low-side FET gate pulls in fault conditions, making the ATL432 a compact, low-cost OVP building block.
推薦
推薦產品摘要
工程參考資料，適用於 ATL432LIBIDBZR — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | ATL432LIAIDBZR | ATL432LIBIDBZRQ1 | TL432LIBIDBZR | TL431LIBIDBZR |
|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | SOT-23-3 (DBZ) | SOT-23-3 (DBZ) - same | SOT-23-3 (DBZ) - same | SOT-23-3 (DBZ) - same | SOT-23-3 (DBZ) - same |
| Reference Voltage | 2.5 V | 2.5 V | 2.5 V | 2.5 V | 2.5 V |
| Initial Accuracy | ±0.5% (B grade) | ±1% (A grade) | ±0.5% (B grade) | ±1% to ±2% (grade dependent) | ±1% to ±2% (grade dependent) |
| Cathode Voltage Range | 2.5 V to 36 V | 2.5 V to 36 V | 2.5 V to 36 V | 2.5 V to 36 V | 2.5 V to 36 V |
| Minimum Cathode Current | ~100 uA (low-Iq) | ~100 uA (low-Iq) | ~100 uA (low-Iq) | Higher Imin than ATL43x | Higher Imin than ATL43x |
| Pinout (DBZ) | 1=K, 2=REF, 3=A (inverted TL432) | 1=K, 2=REF, 3=A | 1=K, 2=REF, 3=A | 1=REF, 2=K, 3=A (inverted) | 1=REF, 2=K, 3=A |
| Automotive Grade | No | No | Yes (AEC-Q100) | No | No |
| Operating Temperature | -40C to +125C | -40C to +125C | -40C to +125C | -40C to +125C | -40C to +125C |
主要差異化特點
- Lower minimum cathode current (low-Iq) than legacy TL432 (對比TL432LIBIDBZR)
- Tighter initial accuracy option (B grade ±0.5%) (對比TL432LIBIDBZR)
- Pinout inverted vs TL432 (pin 1 = Cathode) (對比TL432LIBIDBZR)
設計說明
Do not confuse the ATL432 DBZ pinout (pin 1 = Cathode, pin 2 = Reference) with the TL432 DBZ pinout (pin 1 = Reference, pin 2 = Cathode). According to the TI ATL432 product page, swapping pins 1 and 2 will produce a reference that does not regulate. Verify the footprint marking against the TI datasheet before PCB assembly.
Cathode current must stay above the minimum Imin (~100 uA for ATL432) under all operating conditions, including no-load. For a 12 V cathode rail with a 10 kohm upper resistor, the resistor alone supplies only ~1 mA; ensure the load draws the balance or add a bias resistor. Operating below Imin causes loss of accuracy and possible dropout.
Place the ATL432LIBIDBZR as close as possible to the load or to the optocoupler it drives, keeping the reference-pin trace short to prevent noise pickup. Use a 0.1 uF ceramic bypass capacitor on the cathode when driving high-impedance or capacitive loads, and keep the resistor-divider traces away from switching nodes to avoid coupling noise into the reference voltage.
Estimated: Power dissipation = (Vin - Vka) x Ik. For Vin=36 V, Vka=2.5 V, Ik=15 mA, dissipation = 0.50 W. With the SOT-23-3 (DBZ) theta_JA around 200 C/W (per typical JEDEC test board), junction temperature rises ~100C above ambient. For high-cathode-voltage high-current applications, calculate Pd and Tj before committing to the DBZ package.
合規資訊
Standard ATL432LIBIDBZR is not AEC-Q100 qualified; the ATL432LIBIDBZRQ1 suffix is the qualified option for automotive.
