The LT3742 is a dual step-down DC/DC switching regulator controller from Texas Instruments. The device operates at a frequency of 500kHz and has an input voltage range of 4V to 30V. The output voltage range is 0.8V to VIN. The device uses a 2-phase antiphase output architecture to reduce output voltage ripple and minimize interference with the input supply, reducing the need for input capacitance. The device also integrates a 0.8V voltage reference and a 500kHz current mode control loop, which can provide bias power for N-channel MOSFETs and support low dropout and 100% duty cycle operation. The device also has a built-in soft-start function. The device is available in a 4mm×4mm QFN package and has a very low power consumption of only 20μA in standby mode.
The LT3742 is a dual, constant‑frequency, current‑mode DC/DC step‑down controller that drives high‑side N‑channel MOSFETs. It features a wide 4 V‑30 V input range, 0.8 V‑Vout output range, 500 kHz fixed‑frequency operation, and out‑of‑phase controllers that reduce input ripple and required capacitance.
The device includes built‑in protection such as undervoltage lockout, thermal shutdown, and programmable soft‑start. Pin functions, block diagram, typical performance curves, and package dimensions are provided for designers to implement the controller in applications like satellite set‑top boxes, automotive systems, and super‑capacitor chargers.
| Input Voltage Range | 4 V to 30 V |
|---|---|
| Output Voltage Range | 0.8 V to Viy |
| Switching Frequency | 500 kHz (typical 440‑560 kHz) |
| Package | 24‑lead plastic QFN (4 mm × 4 mm × 0.75 mm) |
| UVLO Pin Voltage (Rising) | 1.20 V (typical) |
The LT3742 operates with an input voltage from 4 V to 30 V.
It is a dual, 2‑phase step‑down controller.
The controller runs at a fixed 500 kHz frequency (typical range 440‑560 kHz).
The device is supplied in a 24‑lead plastic QFN package measuring 4 mm × 4 mm.