PWM测量技术　Free

PWM测量PWM



High Side,

PHASE
Phase 1 Gate Driver IC Controller

Conduct at 10% duty cycle
VIN

Need low Gate charge (nc)

Control FET

L
VO

Sync. FET

C

Low Side,
Phase N

Conduct at 90% duty cycle Need low RDS(ON)

Efficiency
According to Volt-Second balance: (Vin-Vout)*DTs =Vout *(1-D)Ts We can get D = Vout / Vin

UGATE/LGATE
Adaptive Shoot-Through Protection

Multi-Phase
3-Phase 4-Phase
Phase Voltages

Phase Node

Vout Ripple

V_out Ripple

MOSFET
The power dissipation of Mosfet includes two loss components; conduction loss and switching loss. However, only the upper Mosfet has switching losses, since schottky Diode rectifier clamps the switching node before the synchronous rectifier turns on. The gate-changes losses are dissipated by the gate-driver. Large gate charge increases the