JAJSO40 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