7.3.1 VCC
This pin is associated with three functions:
- Biasing power to the integrated circuit
- Input to power on reset (POR) and undervoltage lockout (UVLO) functions
- Voltage sense at one terminal of RS for Q1 current measurement
The voltage must exceed the POR (about 6 V for approximately 400 µs) and the internal UVLO (about 8 V) before normal operation (driving the GATE) may begin. Connections to VCC should be designed to minimize R
S voltage sensing errors and to maximize the effect of C1 and Z1; place C1 at R
S rather than at the IC pin to eliminate transient sensing errors. GATE, PROG, PG, and TIMER are held low when either UVLO or POR are active.