Application Note: SY8120I
High Efficiency, Fast Response, 2.0A, 18V Input Synchronous Step Down Regulator
Features
- • Low RDS(ON) for Internal Switches (Top/Bottom): 130mΩ/105mΩ
- • 4.2-18V Input Voltage Range
- • 2A Output Current Capability
- • 500kHz Switching Frequency Minimize the External Components
- • Stable with 10μF COUT and 1.5μ H Inductor
- • Instant PWM Architecture to Achieve Fast Transient Responses
- • Internal Soft-start Limits the Inrush Current
- • Cycle-by-cycle Peak/Valley Current Limitation
- • Hic-cup Mode Output Short Circuit Protection
- • Thermal Shutdown with Auto Recovery
- • Compact Package SOT23-6
calculation
100K / 22.1K = 3.3V 100K / 16.6K = 4.2V 100K / 15K = 4.6V 100K / 13K = 5V
Rl = 0.6V / (Vout - 0.6V) * Rh
= 0.6V / (3.3V - 0.6V) * 100K = **22.2K**
= 0.6V / (3.4V - 0.6V) * 100K = 21.4K
= 0.6V / (5V - 0.6V) * 100K = 13.3K
= 0.6V / (5.1V - 0.6V) * 100K = **12.8K**
= 0.6V / (4.2V - 0.6V) * 100K = 16.6K
= 0.6V / (4.3V - 0.6V) * 100K = **16.1K**
SCH
