Specifications
| Type | Description |
|---|---|
| Part Number | TPS65251 |
| Manufacturer | Texas Instruments |
| Product Type | LDO Regulator |
| Category | Power Management |
| Component Type | Power_IC |
| Package / Case | 40-pin VQFN RHA, 6.00 mm x 6.00 mm |
| Input Supply Voltage Range | 4.5 to 18 V; recommended operating condition |
| Output Voltage Reference Accuracy | 0.8 V, 1% accuracy; feedback reference |
| Continuous Output Current Buck 1 | 3 A; continuous loading |
| Continuous Output Current Buck 2 | 2 A; continuous loading |
| Continuous Output Current Buck 3 | 2 A; continuous loading |
| Maximum Output Current Buck 1 | 3.5 A; maximum current |
| Maximum Output Current Buck 2 | 2.5 A; maximum current |
| Maximum Output Current Buck 3 | 2.5 A; maximum current |
| Switching Frequency Range | 300 kHz to 2.2 MHz; set by external resistor on ROSC or synchronized to external clock |
| Supported System Input Rails | 5 V, 9 V, 12 V, or 15 V; converter operation |
| Output Voltage Adjustment Range | 0.8 V to near input supply; external resistor divider |
| Phase Operation | Buck 1 operates 180 degrees out of phase with Buck 2 and Buck 3; Buck 2 and Buck 3 run in phase |
| Absolute Maximum Voltage at VIN1, VIN2, VIN3, LX1, LX2, LX3 | -0.3 to 20 V; over operating free-air temperature |
| Absolute Maximum LX Transient Voltage | -3 to 23 V; LX1, LX2, LX3 transient less than 10 ns |
| Absolute Maximum Bootstrap Voltage | -0.3 to 7 V; BST1, BST2, BST3 referenced to LX pin |
| Absolute Maximum Voltage at V7V and COMP Pins | -0.3 to 7 V; V7V, COMP1, COMP2, COMP3 |
| Absolute Maximum Voltage at Logic and Control Pins | -0.3 to 3.6 V; V3V, RLIM1-3, EN1-3, SS1-3, FB1-3, PGOOD, SYNC, ROSC, LOW_P |
| Absolute Maximum Voltage at Ground Pins | -0.3 to 0.3 V; AGND, GND |
| Operating Virtual Junction Temperature | -40 to 125 °C; absolute maximum rating |
| Storage Temperature | -55 to 150 °C; absolute maximum rating |
| ESD Human Body Model | ±2000 V; per ANSI/ESDA/JEDEC JS-001 |
| ESD Charged Device Model | ±500 V; per JEDEC JESD22-C101 |
| Junction Temperature Range | -40 to 125 °C; recommended operating condition |
| Junction-to-Ambient Thermal Resistance | 30 °C/W; RHA VQFN, 40 pins |
| Junction-to-Case Top Thermal Resistance | 25.3 °C/W; RHA VQFN, 40 pins |
| Junction-to-Board Thermal Resistance | 73 °C/W; RHA VQFN, 40 pins |
| Junction-to-Top Characterization Parameter | 0.2 °C/W; RHA VQFN, 40 pins |
| Junction-to-Board Characterization Parameter | 7.6 °C/W; RHA VQFN, 40 pins |
| Junction-to-Case Bottom Thermal Resistance | 1.9 °C/W; RHA VQFN, 40 pins |
| Shutdown Current | 1.3 mA; EN pin low for all converters, TJ=-40°C to 125°C, VIN=12 V, fSW=1 MHz |
| Quiescent Current Low-Power Disabled | 20 mA; converters enabled, no load, Buck1=3.3 V, Buck2=2.5 V, Buck3=7.5 V, L=4.7 µH, fSW=800 kHz |
| Quiescent Current Low-Power Enabled | 1.5 mA; converters enabled, no load, Buck1=3.3 V, Buck2=2.5 V, Buck3=7.5 V, L=4.7 µH, fSW=800 kHz |
| VIN Undervoltage Lockout Rising Threshold | 4.22 V; rising VIN, TJ=-40°C to 125°C, VIN=12 V, fSW=1 MHz unless otherwise noted |
| VIN Undervoltage Lockout Falling Threshold | 4.1 V; falling VIN, TJ=-40°C to 125°C, VIN=12 V, fSW=1 MHz unless otherwise noted |
| VIN UVLO Deglitch Time | 110 µs; both edges |
| V3V Internal Bias Supply Voltage | 3.2 V min, 3.3 V typ, 3.4 V max; ILOAD=0 mA |
| V3V Bias Supply Output Current | 10 mA; VIN=12 V |
| V7V Internal Bias Supply Voltage | 5.63 V min, 6.25 V typ, 6.88 V max; ILOAD=0 mA |
| V7V Bias Supply Output Current | 10 mA; VIN=12 V |
| V7V UVLO Rising Threshold | 3.8 V; rising V7V |
| V7V UVLO Falling Threshold | 3.6 V; falling V7V |
| V7V UVLO Deglitch Time | 110 µs; falling edge |
| Enable Threshold High | 1.55 V min, 1.82 V max; V3p3=3.2 V to 3.4 V, VENX rising |
| Enable High Level | 0.66 x V3V; external GPIO, VENX rising |
| Enable Threshold Low | 0.98 V min, 1.24 V max; V3p3=3.2 V to 3.4 V, VENX falling |
| Enable Low Level | 0.33 x V3V; external GPIO, VENX falling |
| Bootstrap Capacitor Recommendation | 47 nF ceramic capacitor; BST1, BST2, BST3 to corresponding switching node |
| Input Bypass Capacitor Recommendation | 10 µF ceramic capacitor; close to VIN1, VIN2, VIN3 pins |
| V7V Bypass Capacitor Recommendation | 10 µF ceramic capacitor; from V7V to ground |
| V3V Bypass Capacitor Recommendation | 3.3 µF to 10 µF ceramic capacitor; from V3V to ground |
| Power Good Output Type | open-drain, active high default; asserted after all converters are sequenced and within regulation |
| Low-Power Mode Control | active high; LOW_P input enables low-power operation mode |
| Datasheet Status | request_only |
Product Overview
The TPS65251 is a Texas Instruments triple synchronous buck converter for Power_Management designs that need three regulated rails from a shared input supply. Its recommended input supply range is 4.5 to 18 V, and converter operation supports 5 V, 9 V, 12 V, or 15 V system input rails. Buck 1 supports 3 A continuous loading, while Buck 2 and Buck 3 each support 2 A continuous loading.
Output voltage is set with an external resistor divider from 0.8 V to near the input supply. The feedback reference is 0.8 V with 1% accuracy. Switching frequency can be set from 300 kHz to 2.2 MHz with an external resistor on ROSC or synchronized to an external clock.
The device is supplied in a 40-pin VQFN RHA package, 6.00 mm x 6.00 mm. Assembly guidance from the extracted facts includes 47 nF bootstrap capacitors, 10 uF ceramic input bypass capacitors close to VIN pins, a 10 uF V7V bypass capacitor, and a 3.3 uF to 10 uF V3V bypass capacitor.
Key Features
- Triple synchronous buck converter architecture
- 4.5 to 18 V recommended input supply range
- Supports 5 V, 9 V, 12 V, or 15 V rails
- 3 A, 2 A, and 2 A continuous buck outputs
- 3.5 A, 2.5 A, and 2.5 A maximum outputs
- 0.8 V feedback reference with 1% accuracy
- 300 kHz to 2.2 MHz adjustable or synchronized switching
- Output adjustable from 0.8 V to near input supply
- Open-drain active-high power-good output
- Active-high LOW_P input enables low-power operation
Typical Applications
- Three-output regulated power rails
- 5 V system input rails
- 9 V system input rails
- 12 V system input rails
- 15 V system input rails
- Low-power mode supply designs
- Externally synchronized buck supplies
- Sequenced converter power-good monitoring
Procurement Notes
When requesting a quote for TPS65251, 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 input voltage range does TPS65251 support?
TPS65251 has a recommended input supply voltage range of 4.5 to 18 V. The extracted converter-operation facts also list supported system input rails of 5 V, 9 V, 12 V, or 15 V.
How much output current is available from each buck?
Buck 1 supports 3 A continuous loading and 3.5 A maximum current. Buck 2 and Buck 3 each support 2 A continuous loading and 2.5 A maximum current.
How is the TPS65251 switching frequency configured?
The switching frequency range is 300 kHz to 2.2 MHz. It is set by an external resistor on the ROSC pin or synchronized to an external clock, according to the extracted datasheet facts.
What package is specified for TPS65251?
TPS65251 is specified in a 40-pin VQFN RHA package measuring 6.00 mm x 6.00 mm. The listed thermal data is also for the RHA VQFN, 40-pin package.
Technical Review & Sourcing Note
Prepared by LDeepAI Component Sourcing Team. Reviewed for RFQ, documentation and alternative sourcing use. Last updated: July 25, 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.