Analog Devices Inc. DC2991A Demo Circuit for LTC3308A
Analog Devices DC2991A Demo Circuit features the LTC3308A 5V, 4A synchronous step-down Silent Switcher® operating as a 2.0MHz, 3.3V to 1.2V 4A buck regulator. The LTC3308A supports adjustable output voltages from 0.5V to VIN with operating frequencies from 1MHz up to 3MHz. The Analog Devices LTC3308A is a compact, ultra-low emission, high efficiency, and high-speed synchronous monolithic step-down switching regulator. A minimum on-time switching of 22ns enables high VIN to low VOUT conversion ratios at high frequencies.
The DC2991A operating mode may be BURST, SKIP, or Forced Continuous (FC) mode. Setting JP1 to the FC/SYNC position will allow the LTC3308A to sync to a clock frequency from 1MHz to 3MHz. The LTC3308A operates in forced continuous mode when syncing to an external clock. The DC2991A is set to a fixed 2MHz frequency by connecting RT to VIN through a 0Ω resistor (R9). The frequency can be easily changed by removing R9 and setting an appropriate resistor in the R4 location to obtain the desired frequency. The DC2991A also has an EMI filter to reduce conducted EMI. This EMI filter can be included by applying the input voltage at the VIN EMI terminal.
Features
- 2.25V to 5.5V input voltage range
- 1.183V to 1.217V output voltage range
- 4A maximum output current
- 1MHz to 3MHz switching frequency range
- 22ns (typical) top switch minimum on-time
- 100% top switch duty cycle
Applications
- Optical networking, servers, and telecom
- Automotive, industrial, and communications
- Distributed DC power systems (POL)
- FPGA, ASIC, and μP core supplies
Test Setup
Resources
Related Product
Analog Devices Inc. LTC3308A/B Synchronous Step-Down Silent Switcher™
Very small, high efficiency, low noise, monolithic synchronous 4A step-down DC/DC converter.