The LM27402SQX/NOPB is a voltage-mode, synchronous, DC/DC step-down controller with losslessinductor DCR current sensing capability. Sensing the inductor current eliminates the need to addresistive powertrain elements, which increases overall efficiency and facilitates accurate,continuous current sensing. A 0.6-V ±1% voltage reference enables high accuracy and low voltagecapability at the output. An input operating voltage range of 3 V to 20 V makes the LM27402suitable for a large variety of input rails.
The LM27402SQX/NOPB voltage-mode control loop incorporates input voltage feed forward to maintainstability throughout the entire input-voltage range. The switching frequency is adjustable from 200kHz to 1.2 MHz. Dual, high-current, integrated MOSFET drivers support largeQG, low RDS(on) power MOSFETs. A power-good indicatorprovides power-rail-sequencing capability and output fault detection. An adjustable external softstart limits inrush current and provides monotonic output control during start-up. Other featuresinclude external tracking of other power supplies, integrated LDO bias supply, and synchronizationcapability.
Feature
- 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
- 16-Pin HTSSOP and WQFN Packages
- Create a Custom Design Using the LM27402 With the WEBENCH Power Designer
