Specifications
| Type | Description |
|---|---|
| Part Number | TL431IPK |
| Manufacturer | Texas Instruments |
| Product Type | LDO Regulator |
| Category | Power Management |
| Component Type | Power_IC |
| Package Case | PK SOT-89; package body dimensions not provided in excerpt |
| Device Function | Three-terminal adjustable shunt regulator; TL431/TL432 family description |
| Output Voltage Adjustment Range | Vref to 36 V; set with two external resistors |
| Nominal Reference Voltage | Approximately 2.5 V; general description |
| Initial Reference Voltage Tolerance | 2%; standard grade / blank accuracy grade; applicable to TL431I without A or B suffix |
| Operating Free-Air Temperature Grade | -40°C to 85°C; I temperature grade |
| Package | PK SOT-89; TL431...PK package |
| Cathode Pin | Pin 3; TL431x PK package |
| Reference Pin | Pin 1; TL431x PK package |
| Anode Pin | Pin 2; TL431x PK package |
| Absolute Maximum Cathode Voltage | 37 V; with respect to anode, over operating free-air temperature range |
| Absolute Maximum Continuous Cathode Current Range | -100 mA to 150 mA; over operating free-air temperature range |
| Absolute Maximum Reference Input Current | -0.05 mA to 10 mA; over operating free-air temperature range |
| Operating Junction Temperature Range | 150°C max; absolute maximum rating |
| Storage Temperature Range | -65°C to 150°C; absolute maximum rating |
| ESD Rating HBM | ±2000 V; human body model per ANSI/ESDA/JEDEC JS-001 |
| ESD Rating CDM | ±1000 V; charged-device model per JEDEC JESD22-C101 |
| Thermal Resistance Junction-to-Ambient | 52°C/W; PK package |
| Thermal Resistance Junction-to-Case Top | 9°C/W; PK package |
| Recommended Cathode Voltage | Vref to 36 V; recommended operating conditions |
| Recommended Continuous Cathode Current Range | 1 mA to 100 mA; recommended operating conditions |
| Recommended Operating Free-Air Temperature | -40°C to 85°C; TL43xxI devices |
| Reference Voltage | 2440 mV min, 2495 mV typ, 2550 mV max; TL431I/TL432I, VKA=Vref, IKA=10 mA, TA=25°C |
| Reference Input Voltage Deviation Over Temperature | 5 mV typ, 50 mV max; TL431I all other devices, VKA=Vref, IKA=10 mA |
| Reference Voltage Change Ratio | -1.4 mV/V typ, -2.7 mV/V max; TL431I, IKA=10 mA, ΔVKA=10 V - Vref |
| Reference Voltage Change Ratio | -1 mV/V typ, -2 mV/V max; TL431I, IKA=10 mA, ΔVKA=36 V - 10 V |
| Reference Input Current | 2 µA typ, 4 µA max; TL431I, IKA=10 mA, R1=10 kΩ, R2=∞ |
| Reference Input Current Deviation Over Temperature | 0.8 µA typ, 2.5 µA max; TL431I, IKA=10 mA, R1=10 kΩ, R2=∞ |
| Minimum Cathode Current for Regulation | 0.4 mA typ, 1 mA max; TL431I, VKA=Vref |
| Off-State Cathode Current | 0.1 µA typ, 1 µA max; TL431I, VKA=36 V, Vref=0 V |
| Dynamic Impedance | 0.2 Ω typ, 0.5 Ω max; TL431I, VKA=Vref, f≤1 kHz, IKA=1 mA to 100 mA |
| Datasheet Status | request_only |
Product Overview
The TL431IPK is a Texas Instruments precision programmable shunt reference classified under Power_Management. It functions as a three-terminal adjustable shunt regulator, with its output voltage set by two external resistors across a range from Vref to 36 V. The nominal reference voltage is approximately 2.5 V, and the TL431I standard grade has a 2% initial reference voltage tolerance.
For the PK SOT-89 package, the device pinout places the reference terminal on pin 1, the anode on pin 2, and the cathode on pin 3. The excerpt identifies the package as PK SOT-89, but does not provide package body dimensions.
Recommended operation covers cathode voltage from Vref to 36 V, continuous cathode current from 1 mA to 100 mA, and -40°C to 85°C free-air temperature for TL43xxI devices. Electrical data includes 2440 mV minimum, 2495 mV typical, and 2550 mV maximum reference voltage at VKA=Vref, IKA=10 mA, and TA=25°C.
Key Features
- Three-terminal adjustable shunt regulator function
- Output adjustable from Vref to 36 V
- Approximately 2.5 V nominal reference voltage
- 2% initial reference voltage tolerance grade
- PK SOT-89 package with defined three-pin layout
- Recommended cathode current range is 1 mA to 100 mA
- Reference voltage is 2495 mV typical at 25°C
- Dynamic impedance is 0.2 Ω typical
- Off-state cathode current is 0.1 µA typical
- Operating free-air temperature range is -40°C to 85°C
Typical Applications
- Adjustable shunt regulation
- Programmable voltage reference circuits
- Resistor-set reference outputs
- Power management reference nodes
- Cathode current regulation circuits
- Temperature-graded industrial designs
Procurement Notes
When requesting a quote for TL431IPK, buyers should confirm the manufacturer, package or case, required quantity, target date code, compliance documents, packing method, destination country and expected delivery schedule.
If alternatives are acceptable, buyers should share the approved vendor list, required electrical or optical limits, package constraints and qualification requirements. Any alternative part should be reviewed by the buyer's engineering team before production use.
For power IC and power device sourcing, voltage rating, current rating, power dissipation, package thermal performance, protection features, qualification grade and application conditions should be reviewed before approval.
FAQ
What type of device is the TL431IPK?
The TL431IPK is a Texas Instruments precision programmable shunt reference. The extracted datasheet facts describe it as a three-terminal adjustable shunt regulator in the TL431/TL432 family.
What package and pinout does TL431IPK use?
The TL431IPK uses the PK SOT-89 package. For the TL431x PK package, the reference terminal is pin 1, the anode is pin 2, and the cathode is pin 3.
What voltage range can the TL431IPK regulate across?
The output voltage adjustment range is Vref to 36 V when set with two external resistors. The recommended cathode voltage is also specified as Vref to 36 V.
What operating temperature range applies to this device?
For the I temperature grade and TL43xxI devices, the recommended operating free-air temperature range is -40°C to 85°C. The storage temperature range is -65°C to 150°C.
Technical Review & Sourcing Note
Prepared by LDeepAI Component Sourcing Team. Reviewed for RFQ, documentation and alternative sourcing use. Last updated: June 30, 2026.
This page is based on manufacturer datasheet information and LDeepAI sourcing review. Specifications should be verified against the official manufacturer datasheet before final procurement or design approval. Final electrical, optical and reliability approval should be confirmed by the buyer's engineering team.