ISL6262CRZ Intersil, ISL6262CRZ Datasheet - Page 20

• Manufacturer Part Number: ISL6262CRZ
• Description: IC CORE REG 2PHASE 48-QFN
• Manufacturer: Intersil

Specifications of ISL6262CRZ

• Applications: Converter, Intel IMVP-6
• Voltage - Input: 5 ~ 25 V
• Number Of Outputs: 1
• Voltage - Output: 0.3 ~ 1.5 V
• Operating Temperature: -10°C ~ 100°C
• Mounting Type: Surface Mount
• Package / Case: 48-VQFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Setting the Switching Frequency - FSET
The R
architecture. The switching frequency can increase during
the application of a load to improve transient performance.
It also varies slightly due changes in input and output voltage
and output current, but this variation is normally less than
10% in continuous conduction mode.
Refer to Figure 26, the resistor connected between the VW
and COMP pins of the ISL6262 adjusts the switching
window, and therefore adjusts the switching frequency. The
R
converter operating in CCM can be determined using the
following relationship, where R
switching period is in µs. Place a 47pF capacitor in parallel
with the frequency set resistor for better noise immunity.
In discontinuous conduction mode (DCM), the ISL6262 runs
in period stretching mode. The switching frequency is
dependent on the load current level. In general, the lighter
load, the slower switching frequency. Therefore, the
switching loss is much reduced for the light load operation,
which is important for conserving the battery power in the
portable application.
Voltage Regulator Thermal Throttling
lntel® IMVP-6 technology supports thermal throttling of the
processor to prevent catastrophic thermal damage to the
voltage regulator. The ISL6262 features a thermal monitor
R
FSET
ISEN1
OC
FSET
VDIFF
INTERNAL TO
ISL6262
3
(
ISEN1
resistor that sets up the switching frequency of the
kΩ
modulator scheme is not a fixed frequency PWM
0.018µF
)
FIGURE 31. SIMPLIFIED SCHEMATIC FOR DROOP AND DIE SENSING WITH INDUCTOR DCR CURRENT SENSING
-
≅
+
(
+
+
period μs
ISEN2
10µA
R
OPN2
RTN
1
1
+
(
+
-
-
ISEN2
) 0.5
0.018µF
–
82nF
DROOP
VSEN
20
) 1.56
FSET
•
+
-
DROOP
OCSET
VSUM
10
is in kΩ and the
DFB
R
VCC_SENSE
VSS_SENSE
opn1
VO'
R
drp2
R
OCSET
R
TO V
drp1
Cn
TO PROCESSOR
SOCKET KELVIN
CONNECTIONS
(EQ. 4)
OUT
R
VO'
R
SERIES
NTC
ISL6262
VSUM
R
PAR
VO'
which senses the voltage change across an externally
placed negative temperature coefficient (NTC) thermistor.
Proper selection and placement of the NTC thermistor
allows for detection of a designated temperature rise by the
system.
Figure 32 shows the thermal throttling feature with
hysteresis. At low temperature, SW1 is on and SW2
connects to the 1.18V side. The total current going into NTC
pin is 60µA. The voltage on NTC pin is higher than threshold
voltage of 1.18V and the comparator output is low. VR_TT#
is pulling up high by the external resistor.
V
FIGURE 32. CIRCUITRY ASSOCIATED WITH THE THERMAL
NTC
VSUM
VSUM
+
-
R
R
I
NTC
I
NTC
PHASE1
s
PHASE2
RS
RS
THROTTLING FEATURE IN ISL6262
1.20V
54µA
ISEN2
ISEN1
R
L
L2
R
SW2
2
L1
6µA
SW1
L 1
1.18V
+
-
VO'
+
Vdcr
C
C L1
L2
VO'
+
2
DCR
INTERNAL TO
Vdcr
DCR
-
ISL6262
RO1
1
-
R
O2
May 15, 2006
ESR
C
V
BULK
OUT
VR_TT#
FN9199.2