Demonstration circuit 1687B features the LTC3115-1, a high voltage monolithic synchronous buck-boost converter.
The DC1687B demo board has two user-selectable operating modes: Burst Mode® operation and forced continuous operation (fixed frequency PWM) (JP1). There is also an accurate programmable RUN pin which is used to enable the converter (JP2).
The DC1687B operates with a 2.7V to 40V input voltage range. The demo board has been designed with the output voltage set to 5V. The LTC3115-1 incorporates a proprietary low noise switching algorithm which optimizes efficiency with input voltages above, below or equal to the output voltage and ensures seamless transitions between operating modes.
The demo board has been programmed to operate at 1MHz in PWM mode to optimize small size with high efficiency operation.
The demo board also has optional provisions to back feed VCC in order to increase efficiency in some 5V output applications. There is also a provision for an optional Schottky diode from SW2 to VOUT for applications where VOUT is greater than 20V and short circuit protection is desired. Consult the data sheet for more information on these options.
The LTC3115-1 data sheet has detailed information about the operation, specifications, and applications of the part. The data sheet should be read in conjunction with this quick start guide.