Linear Technology Corp. recently introduced the LTC3124 two-phase, 3-MHz current-mode synchronous boost DC/DC converter. It features output disconnect and inrush current limiting. Dual-phase operation has the benefit of reducing peak inductor and capacitor ripple currents. This allows equivalent performance to be achieved in the power supply design with smaller valued inductors and capacitors.
The LTC3124 incorporates low resistance MOSFETs with an RDS(ON) of 130mΩ (N-channel) and 200mΩ (P-channel) to deliver efficiencies as high as 95%. The output disconnect feature allows the output to be completely discharged at shutdown and reduces switch-on inrush. An input pin can be used to configure the LTC3124 for continuous frequency mode to give low-noise operation. Additional features include external synchronization, output overvoltage protection, and robust short-circuit protection.
LTC3124′s main features:
- VIN Range: 1.8 V to 5.5 V, 500 mV after start-up
- Adjustable output voltage: 2.5 V to 15 V
- 1.5-A Output current for VIN = 5 V and VOUT = 12 V
- Dual-phase control reduces output voltage ripple
- Output disconnects from input when shut down
- Synchronous rectification: up to 95% efficiency
- Inrush current limit
- Up to 3-MHz programmable switching frequency synchronizable to external clock
- Selectable Burst Mode operation: 25-µA IQ
- Output Overvoltage Protection
- Internal soft-start
- < 1 µA IQ in shutdown
The LTC3124EDHC and LTC3124EFE are both available from stock in 16-lead 3 mm x 5 mm DFN and thermally enhanced TSSOP packages, respectively. One-thousand-piece pricing starts at $3.26 each.