ISL97645 Intersil Corporation, ISL97645 Datasheet - Page 11

• Manufacturer Part Number: ISL97645
• Description: Boost VON Slice VCOM
• Manufacturer: Intersil Corporation

Gate Pulse Modulator Circuit
The gate pulse modulator circuit functions as a three way
multiplexer, switching VGHM between ground, VDD1 and
VGH. Voltage selection is provided by digital inputs VDPM
(enable) and VFLK (control). High to low delay and slew
control is provided by external components on pins CE and
RE, respectively. A block diagram of the gate pulse
modulator circuit is shown in Figure 14.
VGH_M
11
FIGURE 14. GATE PULSE MODULATOR CIRCUIT BLOCK DIAGRAM
ISL97645
When VDPM is LOW, the block is disabled and VGHM is
grounded. When VDPM is HIGH, the output is determined
by VFLK. When VFLK goes high, VGHM is pulled to VGH by
a 70Ω switch. When VFLK goes low, there is a delay
controlled by capacitor CE, following which VGHM is driven
to VDD1, with a slew rate controlled by resistor RE. Note
that VDD1 is used only as a reference voltage for an
amplifier, thus does not have to source or sink a significant
DC current.
April 11, 2006
FN9263.0