1.8 KiB
@page powerDesign Power Design
Boost
Specifications
The boost converter is used to power the Sunseeker Lighting board. Vin will be the car battery giving a 12V input. This will then be boosted to 16V output, with an output current of 2A. The lights do not need to turn on, the instant the battery turns on, so including a time delay may benefit the board.
LTSpice Simulations
- The LTSpice boost circuit includes input and output resistors for input and output power calculations per Dr. Bazuin. These resistors will not be included in the Altium schematic.
- Dr. Bazuin suggested that an RC circuit can be added at the input for time-delay for output capacitor charging
- Output power = (16V)(2A(max))=32 Watts
- Input power = (12V)(Max FET current). Max FET current should be 2-3x the desired output current
- Rsense = Vsense(min)/IL(max). Vsense is given in LT1619 Datasheet: 40mV(min). For IL, we are using max FET current
- For Rsense, a smaller R value gives less output ripple voltage in simulation.
- Rsense is basically setting the current through the FET
- Voltage divider equation can be found in datasheet for LT1619: Vout=(1.24V)(1+(R1/R2))
- Setting the VC resistor effects the oscillation of the output voltage
Altium
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Inductor is 10uH MSS1210-103MEB. Dr. Bazuin suggested its use as Sunseeker has lots of them
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Replaced the SI9804DY FET (used in LTSpice) with the FDS6680A as the SI is obsolete
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Replaced the MBR735 Schottky (used in LTSpice) with the MBRD835LT4G because 735 is not surface mount
Buck
Specifications
The DC-DC buck regulator is a step-down converter used to lower the 12V input from the car battery to +3.3V to power the telemetry MCU. The part used is the LTC1624 High Efficiency Step-Down Converter.
The initial buck converter design utilized the
LTSpice Simulations
Altium
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