ZHCSQ15 December 2022 TPS22997
PRODUCTION DATA
A capacitor to GND on the CT pin sets the slew rate, and the higher the capacitance the lower the slew rate. The voltage on the CT pin can be as high as 15 V; therefore, the minimum voltage rating for the CT capacitor must be 30 V for optimal performance. Rise times for VBIAS = 5 V are shown below.
CT Capacitor | VIN = 5 V | VIN = 3.3 V | VIN = 1.8 V | VIN = 1.2 V | VIN = 0.8 V |
|---|---|---|---|---|---|
0 pF | 165 μs | 126 μs | 86 μs | 66 μs | 51 μs |
220 pF | 309 μs | 221 μs | 137 μs | 99 μs | 74 μs |
1000 pF | 819 μs | 554 μs | 319 μs | 222 μs | 160 μs |
4700 pF | 3260 μs | 2170 μs | 1210 μs | 829 μs | 575 μs |
The following equation can be used to estimate the rise time for different VIN and CT capacitors at VBIAS = 5 V.
Where:
tR = Rise time in μs
VIN = Input voltage in V
CT = CT capacitance in pF