isl97652 Intersil Corporation, isl97652 Datasheet - Page 18

• Manufacturer Part Number: isl97652
• Description: 4-channel Integrated Lcd Supply With Dual Vcom Amplifiers
• Manufacturer: Intersil Corporation

driven HIGH at a rate primarily controlled by the P1 switch
resistance (RONVGH) and the external capacitive load.
VGHM HIGH to LOW transitions are more complex; take the
case where the block is already enabled (VDPM is HIGH).
When VFLK is HIGH, pin CE is grounded. On the falling
edge of VFLK, a current is passed into pin CE to charge an
18
VGL
VGHM
VFLK
VGL
RE
CE
FIGURE 20. VON-SLICE BLOCK DIAGRAM
VGH
60µA
ISL97652
x248
x248
external capacitor to VREF. This creates a delay, equal to
CE*21300. For example, the delay time is ~10
CE capacitor. At this point, VGHM begins to slew down from
VGH to VGL. The slew current is equal to
Isl = 300/(RE+5kΩ), and the dv/dt slew rate is Isl/Cload.
where Cload is the load capacitance applied to VGHM.
AND TIMING
CONTROL
VDPM
VREF
µ
s for 470pF
November 2, 2007
FN9287.1