Overview
The LM27402SQX/NOPB is a high-performance, voltage-mode, synchronous DC/DC step-down controller produced by Texas Instruments. This device is designed to provide ultrahigh current output for demanding Point-of-Load (POL) applications. It features a wide input-voltage range of 3 V to 20 V, making it compatible with various intermediate bus system rails and battery chemistries. The LM27402 incorporates advanced features such as lossless inductor DCR current sensing, high-current MOSFET drivers, and a voltage-mode control loop with input voltage feedforward to maintain stability across the entire input-voltage range.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Input Voltage Range | 3 V to 20 V | V |
| Output Voltage Range | 0.6 V to 95% of Input Voltage | V |
| Switching Frequency | 200 kHz to 1.2 MHz | Hz |
| Feedback Reference Voltage | 0.6 V ±1% | V |
| Junction Temperature Range | –40°C to 125°C | °C |
| Package Type | 16-Pin WQFN (RUM) and HTSSOP | |
| Thermal Resistance (Junction-to-Ambient) | 35.3 °C/W (WQFN), 39.8 °C/W (HTSSOP) | °C/W |
Key Features
- Wide Input-Voltage Range of 3 V to 20 V
- Inductor DCR or Shunt Resistor Based Overcurrent Protection
- 0.6-V Reference With ±1% FB Accuracy Across Full –40°C to 125°C Junction Temperature Range
- Switching Frequency from 200 kHz to 1.2 MHz
- Output Voltage as High as 95% of Input Voltage
- Integrated High-Current MOSFET Drivers
- Internal VDD Bias Supply LDO Subregulator
- External Clock Synchronization
- Adjustable Soft Start With External Capacitor
- Prebiased Start-up Capability
- Power Supply Tracking
- Voltage-Mode Control With Line Feedforward
- Open-Drain Power-Good Indicator
- Precision Enable With Hysteresis
Applications
- High-Current, Low-Voltage Supply for FPGA and ASIC
- General-Purpose, High-Current Buck Converters
- DC/DC Converters and POL Modules
- Telecom, Datacom, Networking, Distributed Power Architectures
- Cryptocurrency Miners (Bitcoin, Ethereum, Litecoin)
Q & A
- What is the input voltage range of the LM27402?
The input voltage range of the LM27402 is from 3 V to 20 V.
- What is the switching frequency range of the LM27402?
The switching frequency of the LM27402 is adjustable from 200 kHz to 1.2 MHz.
- What type of current sensing does the LM27402 use?
The LM27402 uses inductor DCR or shunt resistor based overcurrent protection.
- What is the feedback reference voltage of the LM27402?
The feedback reference voltage of the LM27402 is 0.6 V with ±1% accuracy across the full junction temperature range.
- What are the package options for the LM27402?
The LM27402 is available in 16-Pin WQFN (RUM) and HTSSOP packages.
- Does the LM27402 have an internal bias supply regulator?
Yes, the LM27402 includes an internal VDD bias supply LDO subregulator.
- Can the LM27402 be synchronized with an external clock?
Yes, the LM27402 supports external clock synchronization.
- How is the soft-start time adjusted in the LM27402?
The soft-start time in the LM27402 is adjusted by connecting an external capacitor to the SS/TRACK pin.
- What is the purpose of the power-good indicator in the LM27402?
The power-good indicator provides power-rail-sequencing capability and output fault detection.
- What is the junction temperature range of the LM27402?
The junction temperature range of the LM27402 is –40°C to 125°C.
