DC3162A

DC3162A demonstration circuit is a 18V, 10A synchronous step-down Silent Switcher® with spread spectrum frequency modulation featuring the LT®8642-1. The demo board is designed for 1.2V output from a 2.8V to 18V input. The LT8642-1 is a compact, low emission, high efficiency, and high speed synchronous monolithic stepdown switching regulator. Special Silent Switcher architecture minimizes EMI emissions. Selectable spread spectrum mode can further improve EMI performance. Fast minimum on-time of 20ns enables high VIN to low VOUT conversion at high frequency. The LT8642-1 switching frequency can be programmed either via a resistor or external clock over a 200KHz to 3MHz range. The default frequency of demo circuit 3162A is 2MHz. The LT8642-1 SYNC/MODE pin on the demo board is grounded (JP1 at BURST position) by default for low ripple Burst Mode® operation. Spread spectrum mode and forced continuous mode can be selected respectively by moving JP1 shunt.

• 1.17V to 1.23V output voltage at R3 = 100Kohm, R7 = 100Kohm, VIN = 12V
• 10A maximum output current
• 2MHz switching frequency at R2 = 17.8Kohm, JP1 = FCM/SYNC
• 83.5% efficiency at VIN = 12V, VBIAS = 3.3V, VOUT = 1.2V, IOUT = 10A