Milpitas, Calif. Linear Technology Corp. has introduced the LT3742, a dual-output, step-down switching regulator DC/DC controller with a 100% duty cycle that produces output voltages up to 30 V for applications such as stepper motors, industrial controls, automotive, distributed power and telecom systems.
The LT3742 can also be configured with one side as a step-down voltage regulator and the other a supercapacitor charger (current source) for capacitor values up to several farads, which is a useful feature in robotic applications when longer hold-up times are needed or where high peak currents are required, said Linear.
The LT3742's 100% duty cycle allows the output voltage to be very close to the input voltage, which is well-suited for battery-powered systems. The 4-V to 30-V input voltage range enables operation from a number of intermediate bus voltages. A simple step-up DC/DC converter is incorporated to generate its own gate drive voltage and also eliminates the extra parts required to drive the high-side MOSFETs. The on-board gate driver powers a single external N-Channel MOSFET for each output, enabling output currents up to 5 A.
A constant 500-kHz operating frequency with current mode control provides fast transient response and easy compensation, said Linear. Output current sensing is precisely measured by monitoring the voltage drop across a sense resistor and protects the converter during overload and short-circuit conditions. In addition, the LT3742 features adjustable soft-start to control the output voltage ramp time and a power good signal for each output.
The LT3742 is offered in a 4 x 4-mm QFN-24 package.
Pricing: Starts at $2.30 in quantities of 1,000.
Linear Technology Corp., 1-408-432-1900, www.linear.com