Overview
The TPS51225CRUKT from Texas Instruments is a dual synchronous, step-down controller designed for cost-effective system-power supply solutions, particularly in notebook, netbook, and tablet computers. This device integrates 100-mA, 5-V and 3.3-V linear regulators (LDOs) and requires minimal external components. It supports high efficiency, fast transient response, and provides a combined power-good signal. The TPS51225CRUKT operates with an input voltage range of 5.5 V to 24 V and supports output voltages of 5 V and 3.3 V, with adjustable ranges of ±10%.
Key Specifications
| Parameter | Min | Max | Unit | |
|---|---|---|---|---|
| Input Voltage Range | 5.5 | - | 24 | V |
| Output Voltages | 4.5 | 5.0 / 3.3 | 5.1 / 3.3 | V |
| Switching Frequency (CH1/CH2) | 300 kHz / 355 kHz | - | - | - |
| VREG5 Output Voltage | 4.85 | 5.0 | 5.10 | V |
| VREG5 Current Limit | 100 | 150 | - | mA |
| Internal Reference Accuracy | 1.99 | 2.00 | 2.01 | V |
| Soft-Start Time | - | 0.8 ms | - | - |
| Operating Temperature Range | -40°C | - | 85°C | - |
Key Features
- Built-in, 100-mA, 5-V and 3.3-V LDOs
- Clock Output for Charge-Pump (260 kHz VCLK)
- Adaptive On-time D-CAP™ Mode Control
- Auto-skip Light Load Operation (TPS51225C)
- OOA Light Load Operation (TPS51225B)
- Internal 0.8-ms Voltage Servo Soft-Start
- Low-Side RDS(on) Current Sensing Scheme with 4500 ppm/°C Temperature Coefficient
- Built-in Output Discharge Function
- Separate Enable Input for Switchers
- Power Good Indicator
- OVP/UVP/OCP Protection
- Non-latch UVLO/OTP Protection
Applications
- Notebook Computers
- Netbook Computers
- Tablet Computers
Q & A
- What is the input voltage range of the TPS51225CRUKT?
The input voltage range is from 5.5 V to 24 V.
- What are the supported output voltages?
The device supports output voltages of 5 V and 3.3 V, with adjustable ranges of ±10%.
- What is the switching frequency for CH1 and CH2?
The switching frequency for CH1 is 300 kHz and for CH2 is 355 kHz during continuous conduction mode (CCM) operation when VIN = 20 V.
- Does the TPS51225CRUKT have built-in LDOs?
- What is the purpose of the VCLK output?
The 260-kHz VCLK signal can be used to drive an external charge pump, generating gate drive voltage.
- How does the device handle light-load conditions?
The TPS51225C automatically reduces switching frequency during light-load conditions to maintain high efficiency.
- What protection features does the TPS51225CRUKT include?
The device includes OVP/UVP/OCP protection and non-latch UVLO/OTP protection.
- What is the soft-start time for the TPS51225CRUKT?
The soft-start time is 0.8 ms.
- What is the operating temperature range of the TPS51225CRUKT?
The operating temperature range is from -40°C to 85°C.
- What package type is the TPS51225CRUKT available in?
The device is available in a 20-pin, 3 mm × 3 mm, QFN package.
