ISL6218CV View Datasheet(PDF) - Renesas Electronics
Part Name
Description
Manufacturer
ISL6218CV
Renesas Electronics
ISL6218CV Datasheet PDF : 19 Pages
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ISL6218
The choice of value for soft-start capacitor is determined by the
maximum slew rate required for the application. An example
calculation is shown in Equation 1. Using the I1 current source
on the SOFT pin as 130µA, and the slew rate of (10mV/s), the
SOFT capacitor is calculated in Equation 1:
CSOFT
ISOURCE
SlewRate
130µA
1µs
10mV
0.012µF
(EQ. 1)
Gate Drive Signals
The ISL6218 provides internal gate drive for a single channel,
Synchronous Buck, Core Regulator.
The ISL6218 was designed with a 4A, low side gate current
sink ability, and a 2A, low-side gate current source ability to
efficiently drive the latest, high performance MOSFETs. This
feature will provide the system designer with flexibility in
MOSFET selection as well as optimum efficiency during all
modes of operation.
Frequency Setting
The power channel switching frequency is set up by a resistor
from the FSET pin to ground. The choice of FSET resistance
for a desired switching frequency can be approximated using
Figure 3. The switching frequency is designed to operate
between 250kHz and 500kHz per phase.
CORE Voltage Programming
The voltage identification pins (VID0, VID1, VID2, VID3, VID4
and VID5) set the DAC output voltage. These pins do not have
internal pull-up or pull-down capability. These pins will
recognize 1.0V, 3.3V or 5.0V CMOS logic. Table 1 shows the
command voltage, VDAC for the 6 bit VID codes.
The IC responds to VID code changes as shown in Figure 5.
PGOOD is masked between these transitions.
250
200
150
100
50
0
250k
500k
750k
1M
CHANNEL SWITCHING FREQUENCY, fSW (Hz)
FIGURE 3. CHANNEL SWITCHING FREQUENCY vs RFSET
FN9101 Rev 6.00
August 6, 2007
ISL6218
IDROOP
ERROR
AMPLIFIER
+
SOFT
RDROOP
+ VDROOP
CSOFT
EA+
FIGURE 4. SOFT-START TRACKING CIRCUITRY SHOWING
INTERNAL CURRENT SOURCES AND “DROOP”
FOR ACTIVE, DEEP AND DEEPER SLEEP
MODES OF OPERATION
VID5
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
TABLE 1. INTEL IMPV-IV VID CODES
VID4 VID3 VID2 VID1 VID0
0
0
0
0
0
0
0
0
0
1
0
0
0
1
0
0
0
0
1
1
0
0
1
0
0
0
0
1
0
1
0
0
1
1
0
0
0
1
1
1
0
1
0
0
0
0
1
0
0
1
0
1
0
1
0
0
1
0
1
1
0
1
1
0
0
0
1
1
0
1
0
1
1
1
0
0
1
1
1
1
1
0
0
0
0
1
0
0
0
1
1
0
0
1
0
1
0
0
1
1
VDAC
1.708
1.692
1.676
1.660
1.644
1.628
1.612
1.596
1.580
1.564
1.548
1.532
1.516
1.500
1.484
1.468
1.452
1.436
1.420
1.404
Page 9 of 19
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