|
ISL78022_14 Datasheet, PDF (11/19 Pages) Intersil Corporation – Automotive Grade TFT-LCD DC/DC with Integrated Amplifiers | |||
|
◁ |
ISL78020, ISL78022
The current through MOSFET is limited to 3A peak. This
restricts the maximum output current based on Equation 3:
IOMAX
=
ââILMT â -Î--2--I--L-â â
Ã
V-----I--N--
VO
(EQ. 3)
Where ÎIL is peak to peak inductor ripple current, and is set
by Equation 4:
ÎIL
=
-V----I--N--
L
Ã
-D---
fS
(EQ. 4)
where fS is the switching frequency.
SLOPE
COMPENSATION
CLOCK
SHUTDOWN
AND START-UP
CONTROL
IFB
IREF
CURRENT
AMPLIFIER
FBB
GM
AMPLIFIER
REFERENCE
GENERATOR
PWM
LX
LOGIC
BUFFER
IFB
VOLTAGE
AMPLIFIER
IREF
COMP
PGND
FIGURE 17. THE BLOCK DIAGRAM OF THE BOOST CONTROLLER
11
FN6386.3
December 23, 2013
|
▷ |