ISC ISL6260

ISL6260, ISL6260B
®
Data Sheet
January 3, 2006
Features
Ordering Information
PART NUMBER
(Note)
TEMP.
RANGE
(°C)
PART
MARKING
• Multiple Current Sensing Approaches Supported
- Lossless DCR Current Sensing
- Precision Resistive Current Sensing
• Supports PSI# and Narrow VDC for Enhanced Battery Life
(EBL) Initiatives
• Superior Noise Immunity and Transient Response
• Thermal Monitor
• Differential Remote Voltage Sensing
• High Efficiency Across Entire Load Range
• Programmable 1, 2 or 3 Power Channels
• Balanced Channel Loading Including Transients
• Small Footprint QFN 40 Lead 6x6 Package
• Pb-Free Plus Anneal Available (RoHS Compliant)
Applications
• Mobile laptop computers
Pinout
DPRSLPVR
VR_ON
VID6
VID5
VID4
VID3
ISL6260CRZ, ISL6260BCRZ (QFN)
TOP VIEW
DPRSTP#
The ISL6260 and ISL6260B have several other key features.
Current sensing can be done using either DCR sensing or
discrete precision resistor sensing. A single NTC thermistor
thermally compensates both the gain and time constant of
the DCR variation. A unity gain, differential amplifier is
provided for remote CPU die sensing. This allows the
voltage on the CPU die to be accurately measured and
regulated per Intel IMVP-6 specifications.
• Microprocessor Voltage Identification Input
- 7-Bit VID Input
- 0.300V to 1.500V in 12.5mV Steps
- Supports VID Changes On-The-Fly
CLK_EN#
Intel Mobile Voltage Positioning is a smart voltage regulation
technology, which effectively reduces power dissipation in Intel
Pentium processors. The ISL6260 and ISL6260B support the
IMVP-6 mobile processor voltage regulation specifications.
ISL6260 and ISL6260B are pin-to-pin compatible. ISL6260B
responds to PSI# signal by adding or dropping PWM2 and
adjusting overcurrent protection accordingly. To improve
audible noise, the DPRSLPVR signal can be used to reduce
slew rates entering and exiting Deeper Sleep.
• Precision Multiphase Core Voltage Regulation
- 0.5% System Accuracy Over Temperature
- Enhanced Load Line Accuracy
3V3
The ISL6260 and ISL6260B provide microprocessor core
voltage regulation by driving up to 3 channels in parallel. The
multiphase buck converter architecture uses interleaved
channels to multiply the output voltage ripple frequency and
reduce output channel currents. The reduction in ripple results
in fewer components, lower component cost, reduced power
dissipation, and smaller implementation area. The ISL6260,
ISL6260B multiphase controller together with the ISL6208 gate
drivers form the basis for a portable power supply solution to
power Intel's next generation mobile microprocessors. The
modulator at the heart of this power system is derived from
Intersil's Robust Ripple Regulator technology, (R3) Compared
with the traditional multiphase buck regulator, the R3
technology multiphase converter has faster transient response.
This is due to the R3 modulator commanding variable switching
frequency during load transients.
PGOOD
Multiphase Core Regulator for IMVP-6
Mobile CPUs
FN9162.1
40
39
38
37
36
35
34
33
32
31
PSI# 1
30 VID2
PGD_IN 2
29 VID1
RBIAS 3
28 VID0
VR_TT# 4
PACKAGE
(Pb-FREE)
PKG.
DWG. #
NTC 5
27 PWM1
26 PWM2
GND PAD
(BOTTOM)
25 PWM3
ISL6260BCRZ -10 to 100 40 Ld 6x6 QFN L40.6x6
VW 8
23 ISEN1
ISL6260BCRZ-T ISL6260BCRZ -10 to 100 40 Ld 6x6 QFN L40.6x6
COMP 9
22 ISEN2
NOTE: Intersil Pb-free plus anneal products employ special Pb-free
material sets; molding compounds/die attach materials and 100% matte
tin plate termination finish, which are RoHS compliant and compatible
with both SnPb and Pb-free soldering operations. Intersil Pb-free
products are MSL classified at Pb-free peak reflow temperatures that
meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020.
FB 10
21 ISEN3
1
11
12
13
14
15
16
17
18
19
20
VDD
ISL6260BCRZ
VSS
24 FCCM
VIN
OCSET 7
VSUM
-10 to 100 40 Ld 6x6 QFN L40.6x6
VO
ISL6260CRZ
DFB
ISL6260CRZ-T
DROOP
SOFT 6
RTN
-10 to 100 40 Ld 6x6 QFN L40.6x6
VSEN
ISL6260CRZ
VDIFF
ISL6260CRZ
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774 | Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright © Intersil Americas Inc. 2005, 2006. All Rights Reserved
All other trademarks mentioned are the property of their respective owners.
ISL6260, ISL6260B
Functional Pin Description
PGOOD
3V3
CLK_EN#
DPRSTP#
DPRSLPVR
VR_ON
VID6
VID5
VID4
VID3
VW
40
39
38
37
36
35
34
33
32
31
A resistor from this pin to COMP programs the switching
frequency. (7kΩ gives approximately 300kHz). VW pin
sources current.
COMP
This pin is the output of the error amplifier.
PSI# 1
30 VID2
PGD_IN 2
29 VID1
RBIAS 3
28 VID0
FB
This pin is the inverting input of error amplifier.
VR_TT# 4
27 PWM1
NTC 5
This pin is the output of the differential amplifier.
26 PWM2
GND PAD
(BOTTOM)
SOFT 6
VDIFF
VSEN
25 PWM3
OCSET 7
24 FCCM
Remote core voltage sense input. Connect to microprocessor die.
VW 8
23 ISEN1
RTN
COMP 9
22 ISEN2
FB 10
21 ISEN3
Remote voltage sensing return. Connect to ground at microprocessor die.
12
13
14
15
16
17
18
19
20
VDIFF
VSEN
RTN
DROOP
DFB
VO
VSUM
VIN
VSS
VDD
DROOP
11
Output of droop amplifier. Output = VO + DROOP.
DFB
Inverting input to droop amplifier.
PSI#
VO
Low load current indicator input. When asserted low,
indicates a reduced load-current condition. For ISL6260B,
when PSI# is asserted low, PWM2 will be disabled.
An input to the IC that reports the local output voltage.
VSUM
PGD_IN
This pin is connected to the current summation junction.
Digital Input. When asserted high, indicates VCCP and
VCC_MCH voltages are within regulation. PGD_IN signal
high is needed for the CLK_EN# to be low and PGOOD to
be high.
VIN
Battery supply voltage, used for feed forward.
VSS
Signal ground; Connect to local controller ground.
RBIAS
147K Resistor to VSS sets internal current reference.
VDD
5V bias power.
VR_TT#
Thermal overload output indicator.
ISEN3
Individual current sensing for channel 3.
NTC
Thermistor input to VRTT# circuit.
ISEN2
Individual current sensing for channel 2.
SOFT
A capacitor from this pin to Vss sets the maximum slew rate
of the output voltage. Soft pin is the non-inverting input of the
error amplifier.
ISEN1
OCSET
Forced Continuous Conduction Mode (FCCM) enable pin to
MOSFET drivers. It will disable diode emulation.
Overcurrent set input. A resistor from this pin to VO sets
DROOP voltage limit for OC trip. A 10µA current source is
connected internally to this pin.
Individual current sensing for channel 1.
FCCM
PWM3
PWM output for channel 3.
2
FN9162.1
January 3, 2006
ISL6260, ISL6260B
PWM2
VR_ON
PWM output for channel 2. For ISL6260B, PSI# low will
make this output tri-state.
Voltage Regulator enable input. A high level logic signal on
this pin enables the regulator.
PWM1
DPRSLPVR
PWM output for channel 1.
Deeper Sleep Enable signal. A high level logic signal on this
pin indicates that the micro-processor is in Deeper Sleep
Mode and indicates that slow entry and exit from C4 should
occur. DPRSLPVR low indicates large charging or
discharging soft pin current, and therefore fast output
voltage transitions.
VID0, VID1, VID2, VID3, VID4, VID5, VID6
VID input with VID0 = LSB.
CLK_EN#
Digital output to enable System PLL Clock; Goes active
10µs after PG_IN is active and Vcore is within 10% of Boot
Voltage.
PGOOD
Power Good open-drain output. Will be pulled up externally
by a 680Ω resistor to VCCP or 1.9kΩ to 3.3V.
DPRSTP#
Deeper Sleep Enable signal. A low level logic signal on this
pin indicates that the micro-processor is in Deeper Sleep
Mode.
3V3
3.3V supply voltage for CLK_EN# logic, such an
implementation will improve power consumption from 3.3V
compared to open drain circuit other wise.
3
FN9162.1
January 3, 2006
ISL6260, ISL6260B
Absolute Maximum Ratings
Thermal Information
Supply Voltage, VDD . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3 - +7V
Battery Voltage, VIN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +25V
Open Drain Outputs, PGOOD, VR_TT# . . . . . . . . . . . . . -0.3 - +7V
ALL OTHER PINS . . . . . . . . . . . . . . . . . . . . . -0.3V to (VDD + 0.3V)
Thermal Resistance
θJA (°C/W) θJC (°C/W)
QFN Package (Notes 1, 2) . . . . . . . . .
30
5.5
Maximum Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . 150°C
Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . .-65°C to +150°C
Maximum Lead Temperature (Soldering, 10s). . . . . . . . . . . . +300°C
Operating Conditions
Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . .-10°C to 100°C
Supply Voltage Range (Typical). . . . . . . . . . . . . . . . . . . . . +5V ±5%
CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the
device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
NOTES:
1. θJA is measured with the component mounted on a low effective thermal conductivity test board in free air. See Tech Brief TB379 for details.
2. For θJC, the “case temp” location is the center of the exposed metal pad on the package underside.
Electrical Specifications
Operating Conditions: VDD = 5V, TA = -10°C to +100°C, unless otherwise noted.
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNITS
2.9
3.5
mA
VR_ON = 0V
1
µA
INPUT POWER SUPPLY
+5V Supply Current
IVDD
VR_ON = 3.3V
+3.3V Supply Current
I3V3
No load on CLK_EN#
1
µA
Battery Supply Current
IVIN
VR_ON = 0V
1
µA
VIN Input Resistance
RVIN
VR_ON = 3.3V
900
Power-On-Reset Threshold
PORr
VDD rising
4.35
PORf
VDD falling
4.00
No load; closed loop, active mode range
VID = 0.75V - 1.50V
-0.5
+0.5
%
VID = 0.5V - 0.7375V
-8
+8
mV
VID = 0.3 - 0.4875V
-15
+15
mV
1.224
V
kΩ
4.5
V
4.15
V
SYSTEM AND REFERENCES
System Accuracy
%Error
(VCC_CORE)
1.176
VBOOT
1.200
Maximum Output Voltage
VCC_CORE(max) VID = [0000000]
1.500
V
Minimum Output Voltage
VCC_CORE(min) VID = [1100000]
0.300
V
0.0
V
VID Off State
VID = [1111111]
RBIAS Voltage
RBIAS = 147kΩ
1.45
1.47
1.49
V
Rfset = 7kΩ, 3 channel operation, Vcomp = 2V
285
300
315
kHz
See Equation 4 Rfset selection
200
500
kHz
-0.3
+0.3
mV
CHANNEL FREQUENCY
Nominal Channel Frequency
fSW(nom)
Adjustment Range
AMPLIFIERS
Droop Amplifier Offset
Error Amp DC Gain
Av0
Error Amp Gain-Bandwidth Product
GBW
FB Input Current
IIN(FB)
4
CL= 20pF
90
dB
18
MHz
10
150
nA
FN9162.1
January 3, 2006
ISL6260, ISL6260B
Electrical Specifications
Operating Conditions: VDD = 5V, TA = -10°C to +100°C, unless otherwise noted. (Continued)
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNITS
2
mV
ISEN
Imbalance Voltage
Maximum of ISENs - Minimum of ISENs
Input Bias Current
20
nA
SOFT CURRENT
-46
-41
-36
μA
±175
±200
±225
μA
DPRSLPVR = 3.3V
-46
-41
-36
μA
IC4EA
DPRSLPVR = 3.3V
36
41
46
μA
IC4EB
DPRSLPVR = 0V
175
200
225
μA
0.26
0.4
V
1
μA
Soft-start current
ISS
SOFT Geyserville Current
IGV
|SOFT-VDAC| >100mV
SOFT Deeper Sleep Entry Current
IC4
SOFT Deeper Sleep Exit Current
SOFT Deeper Sleep Exit Current
POWER GOOD AND PROTECTION MONITORS
PGOOD Low Voltage
VOL
IPGOOD= 4mA
PGOOD Leakage Current
IOH
PGOOD = 3.3V
-1
PGOOD Delay
tpgd
CLK_ENABLE# LOW to PGOOD HIGH
5.5
6.8
8.1
ms
Overvoltage Threshold
OVH
VO rising above setpoint for >1ms
160
200
240
mV
Severe Overvoltage Threshold
OVHS
VO rising for >2µs
1.675
1.7
1.725
V
10
10.2
μA
4
mV
OCSET Reference Current
I(Rbias) = 10µA
9.8
OC Threshold Offset
DROOP rising above OCSET for >150μs
-2
Current Imbalance Threshold
One ISEN above another ISEN for >1.2ms
Undervoltage Threshold
(VDIFF/SOFT)
UVf
VO falling below setpoint for >1.2ms
9
-355
-295
mV
-235
mV
1.0
V
LOGIC THRESHOLDS
VR_ON, DPRSLPVR and PGD_IN
Input Low
VIL(3.3V)
VR_ON, DPRSLPVR and PGD_IN
Input High
VIH(3.3V)
VID0-VID6, PSI#, DPRSTP# Input
Low
VIL(1.0V)
VID0-VID6, PSI#, DPRSTP# Input
High
VIH(1.0V)
2.3
V
0.3
0.7
V
V
PWM
PWM (PWM1-PWM3) Output Low
VOL(5.0V)
Sinking 5mA
1.0
V
FCCM Output Low
VOL_FCCM
Sinking 3mA
1.0
V
PWM (PWM1-PWM3) and FCCM
Output High
VOH(5.0V)
Sourcing 5mA
3.5
PWM = 2.5V
-1
NTC Source Current
NTC = 1.3V
53
Over-Temperature Threshold
V (NTC) falling
1.165
PWM Tri-State Leakage
V
1
μA
60
67
μA
1.18
1.2
V
6.5
9
Ω
THERMAL MONITOR
VR_TT# Low Output Resistance
RTT
I = 20mA
CLK_EN# High Output Voltage
VOH
3V3 = 3.3V, I = -4mA
CLK_EN# Low Output Voltage
VOL
I = 4mA
CLK_EN# OUTPUT LEVELS
5
2.9
3.1
0.26
V
0.4
V
FN9162.1
January 3, 2006
ISL6260, ISL6260B
Typical Operating Performance 3 Phase, DCR Sense, (1) 7821, (2) 7832 per phase, 300kHz, 0.5µH
1.46
90
VOUT (V)
Vout(V)
Efficiency (%)
Efficiency(%)
100
80
70
Vin = 8.0V
Vin = 12.6V
Vin = 19.0V
60
10
10
Vin = 8.0V
1.42
Vin = 12.6V
1.4
Vin = 19.0V
1.38
1.36
1.34
50
11
1.44
1.32
100
100
0
IOUT (A)
10
20
Iout(A)
40
50
Iout(A)
FIGURE 1. ACTIVE MODE EFFICIENCY, 3 PHASE, CCM,
PSI# = HIGH, VID = 1.4375V
FIGURE 2. ACTIVE MODE LOAD LINE, 3 PHASE, CCM,
PSI# = HIGH VID= 1.435V
100
1.44
90
80
70
Vout (V)
Efficiency (%)
Efficiency(%)
30
IOUT (A)
Vin = 8.0V
Vin = 12.6V
60
1.43
Vin = 8.0V
1.42
Vin = 12.6V
Vin = 19.0V
1.41
1.4
1.39
1.38
Vin = 19.0V
1.37
50
1.36
0.1
1
10
0
10
IOUT
(A)
Iout(A)
20
FIGURE 3. DEEPER SLEEP MODE EFFICIENCY, 3 PHASE,
DCM OPERATION, PSI# = LOW, VID = 1.4375V
FIGURE 4. DEEPER SLEEP MODE LOAD LINE, 3 PHASE,
CCM, PSI# = LOW VID= 1.435V
0.76
100
Vin = 8.0V
0.75
Vin = 12.6V
0.74
80
Vout(V)
Efficiency (%)
90
70
Vin = 19.0V
0.73
0.72
0.71
0.7
V in = 8 .0 V
60
30
Iout (A)
V in = 12 .6 V
0.69
V in = 19 .0 V
50
0.68
0.1
1
Iout (A)
10
0
10
20
30
Iout(A)
FIGURE 5. DEEPER SLEEP MODE EFFICIENCY, 3 PHASE,
DCM OPERATION, PSI# = LOW, VID = 0.75V
6
FIGURE 6. DEEPER SLEEP MODE LOAD LINE, 3 PHASE,
DCM OPERATION, PSI# = LOW, VID = 0.75V
FN9162.1
January 3, 2006
ISL6260, ISL6260B
100
100
90
90
Efficiency (%)
Efficiency (%)
Typical Operating Performance 3 Phase, DCR Sense, (1) 7821, (2) 7832 per phase, 300kHz, 0.5µH (Continued)
80
70
Vin = 8.0V
Vin = 12.6V
60
Vin = 12.6V
70
Vin = 19.0V
50
1
10
Iout (A)
100
FIGURE 7. ACTIVE MODE EFFICIENCY, 2 PHASE, CCM,
PSI# = HIGH, VID = 1.4375V
0.1
1
Iout (A)
10
FIGURE 8. DEEPER SLEEP MODE EFFICIENCY, 2 PHASE,
DCM OPERATION, PSI# = LOW, VID = 1.4375V
100
1.44
Vin = 8.0V
1.42
90
Vin = 12.6V
Vin = 19.0V
1.4
Vout (V)
Efficiency (%)
Vin = 8.0V
60
Vin = 19.0V
50
80
70
Vin = 8.0V
Vin = 12.6V
Vin = 19.0V
60
1.38
1.36
1.34
1.32
50
0.1
1
Iout (A)
0
10
10
20
30
40
50
Iout (A)
FIGURE 9. DEEPER SLEEP MODE EFFICIENCY, 2 PHASE,
DCM OPERATION, PSI# = LOW, VID = 0.75V
FIGURE 10. ACTIVE MODE LOAD LINE, 2 PHASE, CCM,
PSI# = HIGH, VID = 1.435V
0.76
1.44
1.43
1.42
Vin = 8.0V
0.75
Vin = 12.6V
0.74
Vin = 19.0V
1.41
Vout (V)
Vout (V)
80
1.4
1.39
Vin = 8.0V
Vin = 12.6V
0.73
Vin = 19.0V
0.72
0.71
1.38
0.7
1.37
0.69
0.68
1.36
0
10
20
30
Iout (A)
FIGURE 11. DEEPER SLEEP MODE LOAD LINE, 2 PHASE,
DCM OPERATION, PSI# = LOW, VID = 1.4375V
7
0
10
20
30
Iout (A)
FIGURE 12. DEEPER SLEEP MODE LOAD LINE, 2 PHASE, DCM
OPERATION, PSI# = LOW, VID = 0.75V
FN9162.1
January 3, 2006
ISL6260, ISL6260B
Typical Operating Performance
[email protected]
Vsoft
[email protected]
Vout
VR_ON
PGD_IN
IMVP-6 Pgood
CLK_EN#
FIGURE 13. SOFT-START WAVEFORM SHOWING SLEW RATE
OF 2mV/µs, 0V TO 1.2V (BOOT VOLTAGE)
FIGURE 14. SOFT-START WAVEFORM SHOWING CLK_EN#
AND IMVP-6 PGOOD
Vout
Vin
Vout
FIGURE 15. 12V-18V INPUT LINE TRANSIENT RESPONSE
FIGURE 16. SOFT-START INRUSH CURRENT, VIN = 8V
FIGURE 17. 3 PHASE CURRENT BALANCE, FULL LOAD = 50A
FIGURE 18. 2 PHASE CURRENT BALANCE, FULL LOAD = 50A
8
FN9162.1
January 3, 2006
ISL6260, ISL6260B
Typical Operating Performance (Continued)
Vout
COMP PIN
FIGURE 19. TRANSIENT LOAD RESPONSE, 40A LOAD STEP
@ 200A/µs, 3 PHASE
FIGURE 20. TRANSIENT LOAD 3 PHASE OPERATION CURRENT BALANCE
FIGURE 21. TRANSIENT LOAD 3 PHASE OPERATION, ZOOM
OF RISING EDGE CURRENT BALANCE
FIGURE 22. TRANSIENT LOAD 3 PHASE OPERATION, ZOOM
OF FALLING EDGE CURRENT BALANCE
VID MSB
VID MSB
Vout
FIGURE 23. ISL6260, VID MSB BIT CHANGE FROM 1.4375V
TO 0.65V SHOWING 9mV/µs SLEW RATE,
DPRSLPVR = 0, DPRSTP# = 1
9
Vout
FIGURE 24. SLEW RATE ENTERING C4, VID MSB BIT
CHANGE FROM 1.4375V TO 0.65V SHOWING
2mV/µs SLEW RATE, DPRSLPVR = 1, DPRSTP# = 0
FN9162.1
January 3, 2006
ISL6260, ISL6260B
Typical Operating Performance (Continued)
Vout
Vout @ 1.7V
PWM
DPRSTP# AND PSI#
Vout @ 0.85V
DPRSLPVR AND MSB
FIGURE 25. C4 ENTRY AND EXIT SLEW RATES WITH
DPRSLPVR AND DPRSTP# (ISL6260)
FIGURE 26. 1.7V OVP SHOWING OUTPUT PULLED LOW TO
0.85V AND PWM TRI_STATE
PWM
PWM
Vout
Iphase
Pgood
Vout
FIGURE 27. UNDERVOLTAGE RESPONSE SHOWING PWM
TRI-STATE, VOUT < VID - 300mV
Pgood
FIGURE 28. OCP - RESPONSE
PWM
PSI#
CLK_EN#
Iphase
Vout
Vout
Pgood
FIGURE 29. OCP - SHORT CIRCUIT PROTECTION
10
Phase 2
FIGURE 30. ISL6260B, PHASE ADDING AND DROPPING IN
ACTIVE MODE, LOAD CURRENT = 15A
FN9162.1
January 3, 2006
ISL6260, ISL6260B
Typical Operating Performance (Continued)
Phase 3 current
PSI#
CLK_EN#
Vout
PHASE 1 CURRENT
PHASE 2
CURRENT
PHASE 2
PHASE 2
FIGURE 31. ISL6260B PHASE ADDING AND DROPPING IN
DEEPER SLEEP MODE, LOAD CURRENT = 4.35A
FIGURE 32. ISL6260B, INDUCTOR CURRENT WAVEFORM
WITH PHASE ADDING AND DROPPING IN DCM
OR DEEPER SLEEP MODE
PHASE 3
CURRENT
PHASE 1 CURRENT
PHASE 1 CURRENT
PHASE 2 CURRENT
PHASE 2 CURRENT
Pgood
PHASE 2
FIGURE 33. ISL6260B, INDUCTOR CURRENT WAVEFORM
WITH PHASE ADDING AND DROPPING IN CCM
OR ACTIVE MODE
11
FIGURE 34. ISL6260B, OVERCURRENT DUE TO PHASE
DROPPING
FN9162.1
January 3, 2006
ISL6260, ISL6260B
Simplified Application Circuit for DCR Current Sensing
disabled, allows the regulator to operate in Diode Emulation
for improved light load efficiency.
Figure 35 shows a simplified application circuit for the
ISL6260 or ISL6260B converter. Both the MOSFET driver IC
and main control IC are shown. The driver has a forcecontinuous-conduction-mode (FCCM) input, that when
V+5 VIN V+3.3
VIN
VDD
VIN
3V3
V+5
RBIAS
VCC
NTC
PWM1
ISEN1
VR_TT#
VR_TT#
PWM
BOOT
LO
UGATE
ISL6208
PHASE
SOFT
7
VID<0:6>
VIDs
DPRSTP#
RL CL
FCCM
LGATE
GND
ISEN1
DPRSTP#
VO'
ISL6260
DPRSLPVR
VSUM
DPRSLPVR
PSI#
VIN
VO
PSI#
V+5
PGD_IN
MCHOK
CLK_ENABLE#
VCC
PWM
PWM2
CLK_EN#
ISEN2
VR_ON
VR_ON
IMVP6_PWRGD
CO
BOOT
LO
UGATE
ISL6208
PHASE
PGOOD
RL CL
FCCM
Remote
Sense
at CPU
CORE
VSEN
LGATE
GND
ISEN2
RTN
Ri
VSUM
FCCM
C3
R3
V+5
VCC
FB
C1
VO'
VIN
VDIFF
BOOT
R1
PWM
PWM3
ISEN3
COMP
C2
LO
UGATE
ISL6208
RFSET
VSUM
VSUM
VW
PHASE
FCCM
LGATE
GND
OCSET
GND
DFB
DROOP
VO
RL CL
ISEN3
VSUM
RN
VO'
CC
S
VO'
FIGURE 35. TYPICAL APPLICATION CIRCUIT FOR DCR SENSING
12
FN9162.1
January 3, 2006
ISL6260, ISL6260B
Simplified Application Circuit for Resistive Current Sensing
continuous-conduction-mode (FCCM) input, that when
disabled, allows the regulator to operate in Diode Emulation
for improved light load efficiency.
Figure 36 shows a simplified application circuit for the
ISL6260 or ISL6260B converter. Both the MOSFET drivers
and main control IC are shown. The driver has a force
V+5 V+3.3
VIN
VIN
VDD
VIN
3V3
V+5
RBIAS
VCC
NTC
PWM1
ISEN1
VR_TT#
VR_TT#
PWM
BOOT
LO
UGATE
RSEN
ISL6208
SOFT
7
VID<0:6>
PHASE
VIDs
LGATE
GND
DPRSTP#
DPRSTP#
VSUM
FCCM
CL
VO'
ISL6260
DPRSLPVR
DPRSLPVR
PSI#
RL
ISEN1
VIN
VO
PSI#
V+5
PGD_IN
MCHOK
CLK_ENABLE#
CLK_EN#
VCC
PWM2
ISEN2
PWM
VR_ON
VR_ON
IMVP6_PWRGD
CO
BOOT
LO
UGATE
RSEN
ISL6208
PHASE
PGOOD
VSUM
FCCM
Remote
Sense at
CPU
CORE
VSEN
LGATE
GND
ISEN2
RTN
FCCM
VIN
VDIFF
R3
C1
R1
CL
VO'
Ri
C3
RL
V+5
VCC
FB
BOOT
PWM3
ISEN3
COMP
PWM
C2
UGATE
LO
RSEN
ISL6208
RFSET
PHASE
VW
VSUM
VSUM
FCCM
LGATE
GND
OCSET
GND
DFB
DROOP
VSUM
ISEN3
VO
RL
CL
VO'
VO'
FIGURE 36. TYPICAL APPLICATION CIRCUIT FOR DISCRETE RESISTOR CURRENT SENSING
13
FN9162.1
January 3, 2006
Functional Block Diagram
RBIAS
PGOOD
PGD_IN
3V3 CLK_EN#
VIN
VDD
ISEN1 ISEN2 ISEN3
VIN
VO
VID0
PROTECTION
VID2
14
VID3
54µA
POWER
VID1
IBAL
CLK_EN#
LOGIC
GOOD
MONITOR
BALANCE
DAC
DACOUT
VID4
IBAL VDIFF
OC
NTC
FLT
VID5
VR_TT#
VID6
-
FAST_OC OR
WAY-OC
+
1.18V
OC
MODE
CONTROL
FCCM
VIN
VO
1.2V
+
2X
VO
VR_ON
FLT
MODULATOR
MODE
PWM1
SOFT
CONTROL
DPRSLPVR
DPRSTP#
OC
NUMBER OF
PHASES
10µA
VIN
VO
GAIN SELECT
OCSET
FLT
MODULATOR
(ISL6260B ONLY)
-
(1, 2/3, or 1/2)
PWM2
OC
+
VSUM
DFB
OC
+
DROOP
-
DROOP
+
-
VO
PWM3
E/A
+
-
VO
NUMBER OF
PHASES
+
1
-
+
CLOCK
MODE
CONTROL
VIN VO
V O VSEN
RTN
FLT
MODULATOR
+
1
VIN
VDIFF
SOFT FB
COMP
VW
FN9162.1
January 3, 2006
FIGURE 37. SIMPLIFIED BLOCK DIAGRAM
GND
CHANNEL
SELECT
ISL6260, ISL6260B
PSI#
6µA
CURRENT
ISL6260, ISL6260B
Theory of Operation
VDD
Operational Description
The ISL6260 and ISL6260B are multiphase regulators
implementing Intel® IMVP-6 protocol. They can be
programmed for one-, two- or three-channel operation for
microprocessor core applications up to 70A. With their
mating gate driver, the ISL6208, the SL6260 and ISL6260B
give optimum steady-state and transient performance.
At the heart of the ISL6260 and ISL6260B is the patented R3
(Robust Ripple Regulator®) modulator. The R3® modulator
combines the best features of fixed frequency PWM and
hysteretic PWM while eliminating many of their
shortcomings. The ISL6260 and ISL6260B modulator
internally synthesize an analog of the inductor ripple currents
and use hysteretic comparators on those signals to
determine PWM pulse widths. Operating on these largeamplitude, noise-free synthesized signals allows the
ISL6260 and ISL6260B to achieve lower output ripple and
lower phase jitter than conventional hysteretic and fixed
PWM controllers. Unlike conventional hysteretic converters,
the ISL6260 and ISL6260B have an error amplifier that
allows the controller to maintain a 0.5% voltage tolerance.
The hysteresis window voltage rides on the error amplifier
output such that a load current transient results in an
increase in switching frequency to give the R3 regulator a
faster response than conventional fixed frequency PWM
controllers. The sharing of the hysteretic window voltage
also inherently shares the transient load current between the
phases. The individual average phase voltages are
monitored and controlled to equally share the static current
among the phases.
ISL6260B disables PWM2 when PSI# is asserted low.
ISL6260 does not drop phase with PSI# signal.
VR_ON
100µs
10mV/µs
2mV/µs
VBOOT
VID COMMANDED
VOLTAGE
SOFT & VO
20µs
PGD_IN
CLK_EN#
IMVP-6 PGOOD
~7ms
FIGURE 38. SOFT-START WAVEFORMS USING A 20nF SOFT
CAPACITOR
Start-up Timing
With the controller's +5V VDD voltage above the POR
threshold, the start-up sequence begins when VR_ON
exceeds the 3.3V logic HIGH threshold. Approximately
100µs later SOFT and VOUT start ramping up to the boot
voltage of 1.2V. During this interval, the SOFT capacitor is
charged with approximately 40µA. Therefore, if the SOFT
capacitor is selected to be 20nF, the SOFT ramp will be at
about 2mV/µs for a soft-start time of 600µs. Once VOUT is
within 10% of the boot voltage and PGD_IN is HIGH for six
PWM cycles (20µs for frequency = 300kHz), then CLK_EN#
is pulled LOW and the SOFT capacitor is charged up with
approximately 200µA. Therefore, VOUT slews at +10mV/µs
to the voltage set by the VID pins. Approximately seven
milliseconds later, PGOOD is asserted HIGH. A typical startup timing is shown in Figure 38. Similar results occur if
VR_ON or PGD_IN or both are tied to VDD, with the softstart sequence starting 120µs after VDD crosses the POR
threshold.
PGD_IN - LATCH
It should be noted that PGD_IN going low will cause the
converter to latch off. This state will be cleared when VR_ON
is toggled. This feature allows the converter to respond to
other system voltage outages immediately. For ISL6260B
only, PGD_IN de-assertion (0) during normal operation will
make CLK_EN# go high.
15
FN9162.1
January 3, 2006
ISL6260, ISL6260B
Static Operation
After the start sequence, the output voltage will be regulated
to the value set by the VID inputs per Table 1. This Table is
presented in its entirety in the Intel IMVP-6™ specification.
The ISL6260, ISL6260B will control the no-load output voltage
to an accuracy of ±0.5% over the range of 0.75V to 1.5V.
TABLE 1. TRUNCATED VID TABLE FOR INTEL IMVP-6™
SPECIFICATION
VID6
VID5
VID4
VID3
VID2
VID1
VID0
VOUT
0
0
0
0
0
0
0
1.500V
0
0
0
0
0
0
1
1.4875
0
0
0
0
1
0
1
1.4375
0
0
0
0
1
1
1
1.4125
0
0
0
1
0
0
0
1.4000
0
0
1
0
0
0
1
1.2875
0
0
1
1
0
0
0
1.2000
0
0
1
1
1
0
0
1.1500
0
1
0
1
0
0
0
1.0000
0
1
0
1
0
1
1
0.9625
0
1
1
1
1
0
0
0.7500
1
0
0
0
1
0
0
0.6500
1
0
1
0
0
0
0
0.5000
1
1
0
0
0
0
0
0.300
1
1
0
0
0
0
1
Off
1
1
0
0
0
1
0
Off
...
Off
1
1
1
1
1
1
0
Off
1
1
1
1
1
1
1
Off
A fully-differential amplifier allows CPU die voltage sensing
for precise voltage control at the microprocessor die. The
inputs to the amplifier are the VSEN and RTN pins.
As the load current increases from zero, the output voltage
will droop from the VID table value by an amount
proportional to current to achieve the IMVP-6 load line. The
ISL6260 and ISL6260B provide for current to be measured
using resistors in series with the channel inductors as shown
in the application circuit of Figure 36 or using the intrinsic
series resistance of the inductors as shown in the application
circuit of Figure 35. In both cases, signals representing the
inductor currents are summed at VSUM which is the noninverting input to the DROOP amplifier shown in the block
diagram of Figure 37. The voltage at the DROOP pin minus
the output voltage, VO´ is thus a high-bandwidth analog of
the total inductor current. This value is used as an input to
the differential amplifier to achieve the IMVP-6 load line as
well as the input to the overcurrent circuit.
16
When using inductor DCR current sensing, a single NTC
element is used to compensate the positive temperature
coefficient of the copper winding thus sustaining the load-line
accuracy. Procedures to follow in determining component
values are covered in the “Component Selection and
Application” section of the datasheet.
In addition to the total current which is used for DROOP and
OC, the individual channel average currents are also
monitored and are used for balancing the load between the
channels. The IBAL circuit will adjust the channel pulsewidths up or down relative to the other channels to cause the
voltages presented to the ISEN pins to be equal.
The ISL6260 and ISL6260B controller can be configured for
three-, two- or single-channel operation. To disable channel
two and/or channel three, its PWM output pin should be tied
to +5V VDD and the ISEN pins should be grounded. If the
ISL6208 gate driver is populated in an unused channel, its
PWM input pin should be opened in order to turn off its
output. In three-channel operation, the three channel PWM's
are 120 degrees apart, and in two-channel operation they
are 180 degrees apart. The channel PWM frequency is
determined by the value of RFSET as shown in the
“Component Selection and Application” section of this
document.
If the controller is kept in continuous conduction mode
(CCM), the switching frequency may not be constant but it
can maintain the switching ripple within spec. However, it will
be very close to the set value at high input voltage and
heavy load conditions. Selected by setting DPRSLPVR high,
DPRSTP# low, together with PSI# signal (see Table 2),
discontinuous conduction mode (DCM) is allowed. In DCM,
the ISL6260, ISL6260B commands the ISL6208 to turn off
the lower FET after its channel current decays to zero. As
load is further reduced, channel switching frequency will
drop, providing optimized efficiency even at light loading.
Dynamic Operation
Refer to Figure 39. The ISL6260 and ISL6260B respond to
changes in VID command voltage by slewing to new
voltages with a dV/dt set by the SOFT capacitor and by the
state of DPRSLPVR. With CSOFT = 20nF and DPRSLPVR
HIGH, the output voltage will move at ±2mV/µs for large
changes in voltage. For DPRSLPVR LOW, the large signal
dV/dt will be ±10mV/µs. As the output approaches the VID
command voltage, the dV/dt rate moderates to prevent
overshoot. During Geyserville III transitions where there is
one LSB VID step each 5µs, the controller will follow the VID
command with its dV/dt rate of ±2.5mV/µs.
FN9162.1
January 3, 2006
ISL6260, ISL6260B
Vout
10mV/us
-2mV/us
DPRSTP#
PSI#
When PSI# is de-asserted low, ISEN2 pin is connected to
the ISEN pins of the operational phases internally to keep
proper current balance and less current overshoot and
undershoot when the disabled phase is enabled again.
2mV/us
TABLE 2. ISL6260 ISL6260B MODE OF OPERATIONS
DPRS DPR
LPVR STP# PSI#
IMVP-6
Logic
DPRSLPVR
MSB of VID
FIGURE 39. DEEPER SLEEP TRANSITION SHOWING
DPRSLPVR’s EFFECT ON EXIT SLEW RATE
Keeping DPRSLPVR HIGH during VID transitions will result
in reduced dV/dt output voltage changes with resulting
minimized audio noise. For fastest recovery from Deeper
Sleep to Active mode, DPRSLPVR LOW achieves maximum
dV/dt. Therefore, the ISL6260 and ISL6260B are IMVP-6
compliant for DPRSTP# and DPRSLPVR logic.
Intersil's R3 intrinsically has voltage-feed-forward. Highspeed input voltage steps result in insignificant output
voltage perturbations. Refer to Figure 15 in the “Typical
Operating Performance” section of this document for Input
Transient Performance.
In response to load current step increases, the ISL6260 and
ISL6260B will transiently raise the switching frequency so
that response time is decreased and current is shared by all
the channels.
Modes of Operation Programmed by Logic Signals
The operational modes of ISL6260 and ISL6260B are
related to the control signals of DPRSLPVR, DPRSTP#, and
PSI#. ISL6260B responds PSI# signal by adding or dropping
PWM2 and adjusting the overcurrent protection level
accordingly. ISL6260 does not drop phases while in
operation. For example, if the ISL6260B is initially used as
three phase, the PSI# signal will add or drop PWM2 and
leave PWM1 and PWM3 always in operation. Meanwhile,
after PWM2 is dropped, the phase shift between the PWM1
and PWM3 is adjusted from 120 degree to 180 degree and
the overcurrent and the way-overcurrent protection level will
be adjusted to 2/3 of the initial value. If the ISL6260B is
initially used as two phase operation, it is suggested that
PWM1 and PWM2 pair, not PWM1 and PWM3 pair, should
be used such that PSI# signal will enable or disable PWM2
with PWM1 in operation always. The overcurrent and wayovercurrent protection level in two-to-one phase mode
operation will be adjusted as two to one as well. For
ISL6260B, the DCM mode is independent of PSI#, it just
responds to the DPRSLPVR and DPRSTP#. The following
table shows the operation modes of ISL6260 and ISL6260B
with combinations of control logic.
17
Other
Logic
0
1
1
ISL6260
ISL6260B
N phase CCM N phase CCM
CPU
MODE
Active
0
1
0
N phase CCM N-1 phase CCM Active
1
0
1
N phase CCM N phase DCM
1
0
0
N phase DCM N-1 phase DCM Deeper
sleep
0
0
1
N phase CCM N phase CCM
0
0
0
N phase CCM N-1 phase CCM
1
1
1
N phase CCM N phase CCM
1
1
0
N phase CCM N-1phase CCM
Deeper
sleep
Protection
The ISL6260 and ISL6260B provide overcurrent, overvoltage,
and undervoltage protection. Overcurrent protection is tied to
the voltage droop which is determined by the resistors
selected as described in the “Component Selection and
Application” section. After the load-line is set, the OCSET
resistor can be selected to detect overcurrent at any level of
droop voltage. For overcurrent less that twice the OCSET
level, the overload condition must exist for 120µs in order to
trip the OC fault latch. This is shown in Figure 28.
For overload exceeding twice the set level, the PWM outputs
will immediately shut off and PGOOD will go low to maximize
protection due to hard shorts. This protection was referred to
as way-overcurrent.
In addition, excessive phase unbalance due to gate driver
failure will be detected and will shut down the controller after
1ms. The phase unbalance is detected by the voltage on the
ISEN pins if the difference is greater than 9mV.
Undervoltage protection is independent of the overcurrent
limit. If the output voltage is less than the VID set value by
300mV or more, a fault will latch after 1ms in that condition.
The PWM outputs will turn off and PGOOD will go low. This
is shown in Figure 27. Note that most practical core
regulators will have the overcurrent set to trip before the 300mV undervoltage limit.
There are two levels of overvoltage protection and response.
For output voltage exceeding the set value by +200mV for
1ms, a fault is declared. All of the above faults have the
same action taken: PGOOD is latched low and the upper
and lower power FETs are turned off so that inductor current
will decay through the FET body diodes. This condition can
be reset by bringing VR_ON low or by bringing VDD below
POR threshold. When these inputs are returned to their high
operating levels, a soft-start will occur.
FN9162.1
January 3, 2006
ISL6260, ISL6260B
TABLE 3. SUMMARY OF THE FAULT PROTECTION AND RESET OPERATIONS OF ISL6260, ISL6260B
FAULT DURATION
PRIOR TO
PROTECTION
PROTECTION
ACTIONS
FAULT RESET
Overcurrent
120µs
PWMs tri-state, Pgood latched low
VR_ON toggle or VDD toggle
Way-Overcurrent
<2µs
PWMs tri-state, Pgood latched low
VR_ON toggle or VDD toggle
Overvoltage 1.7V
Immediately
Low side MOSFET on until Vcore <0.85V, then PWM
tri-state, Pgood latched low.
VDD toggle
Overvoltage +200mV
1ms
PWMs tri-state, Pgood latched low
VR_ON toggle or VDD toggle
Undervoltage -300mV
1ms
PWMs tri-state, Pgood latched low
VR_ON toggle or VDD toggle
Phase Current Unbalance
1ms
PWMs tri-state, Pgood latched low
VR_ON toggle or VDD toggle
Over Temperature
Immediately
VR_TT# goes low
N/A
Refer to Figure 26. The second level of overvoltage
protection behaves differently. If the output exceeds 1.7V, an
OV fault is immediately declared, PGOOD is latched low and
the low-side FETs are turned on. The low-side FETs will
remain on until the output voltage is pulled down below
0.85V at which time all FETs are turned off. If the output
again rises above 1.7V, the process is repeated. This affords
the maximum amount of protection against a shorted highside FET while preventing output ringing below ground. The
1.7V OV is not reset with VR_ON, but requires that VDD be
lowered to reset. The 1.7V OC detector is active at all times
that the controller is enabled including after one of the other
faults occurs so that the processor is protected against highside FET leakage while the FETs are commanded off.
The ISL6260 and ISL6260B have a thermal throttling
feature. If the voltage on the NTC pin goes below the 1.18V
OT threshold, the VR_TT# pin is pulled low indicating the
need for thermal throttling to the system oversight processor.
No other action is taken within the ISL6260 and ISL6260B in
response to NTC pin voltage.
Fault protection is summarized in Table 3.
Component Selection and Application
Soft-Start and Mode Change Slew Rates
The ISL6260 and ISL6260B use 2 slew rates for various
modes of operation. The first is a slow slew rate, used to
reduce inrush current on start-up. It is also used to reduce
audible noise when entering or exiting Deeper Sleep Mode.
A faster slew rate is used to exit out of Deeper Sleep and to
increase system performance by achieving active mode
regulation more quickly. Note that the SOFT cap current is
bidirectional and is flowing into the SOFT capacitor when the
output voltage is commanded to rise, and out of the SOFT
capacitor when the output voltage is commanded to fall.
The two slew rates are determined by commanding 1 of 2
currents onto the SOFT pin. As can be seen in Figure 40, the
SOFT pin has a capacitance to ground. Also, the SOFT pin
is the input to the error amplifier and is, therefore, the
18
commanded system voltage. Depending on the state of the
system, i.e. Start-Up or Active mode, and the state of the
DPRSLPVR pin, one of the two currents shown in Figure 40
will be used to charge or discharge this capacitor, thereby
controlling the slew rate of the commanded voltage. These
currents can be found under the Soft Current section of the
Electrical Specification Table.
ISL6260(B)
ISS
I2
ERROR
AMPLIFIER
+
SOFT
CSOFT
+
VREF
FIGURE 40. SOFT PIN CURRENT SOURCES FOR FAST AND
SLOW SLEW RATES
The first current, labeled ISS, is given in the Specification
Table as 41μA. This current is used during Soft-Start. The
second current, I2 sums with ISS to get the larger of the two
currents, labeled IGV in the Electrical Specification Table.
This total current is typically 200μA with a minimum of
175μA.
The IMVP-6™ specification reveals the critical timing
associated with regulating the output voltage. The symbol,
Slewrate, as given in the IMVP-6™ specification, will
determine the choice of the SOFT capacitor, CSOFT, by the
following equation:
I GV
C SOFT = -----------------------------------SLEWRATE
FN9162.1
January 3, 2006
ISL6260, ISL6260B
Using a SLEWRATE of 10mV/μs, and the typical IGV value,
given in the Electrical Specification Table of 200μA, CSOFT is
200μA
C SOFT = ------------------ = 0.020μF
10mV
---------------1μs
(EQ. 2)
regulation, as indicated by PGD_IN going high, CLK_EN#
goes low, triggering an internal timer for the IMVP6_PWRGD
signal. This timer allows IMVP6_PWRGD to go high
approximately 7ms after CLK_EN# goes low.
Static Mode of Operation - Processor Die Sensing
A choice of 0.015μF would guarantee a SLEWRATE of
10mV/μs is met for minimum IGV value, given in the
Electrical Specification Table.
Now this choice of CSOFT will then control the start-up
slewrate as well. One should expect the output voltage to
slew to the Boot value of 1.2V at a rate given by the following
equation:
I SS
41μA
dV
mV
- = ----------------------- = 2.73 --------------- = -----------------0.015μF
C SOFT
dt
μs
(EQ. 3)
Generally, when output voltage is approaching its steady
state, its dv/dt will slow down to prevent overshoot. In order
to compensate the slow-down effect, faster initial dv/dt slew
rates can be used with small soft capacitors such as 10nF to
achieve the desired overall dv/dt in the allocated time
interval.
Selecting RBIAS
To properly bias the ISL6260 and ISL6260B, a reference
current is established by placing a 147kΩ, 1% tolerance
resistor from the RBIAS pin to ground. This will provide a
highly accurate, 10μA current source from which OCSET
reference current can be derived.
Care should be taken in layout that the resistor is placed
very close to the RBIAS pin and that a good quality signal
ground is connected to the opposite side of the RBIAS
resistor. Do not connect any other components to this pin as
this would negatively impact performance. Capacitance on
this pin would create instabilities and is to be avoided.
Start-up Operation - CLK_EN# and PGOOD
The ISL6260 and ISL6260B provide a 3.3V logic output pin
for CLK_EN#. The 3V3 pin allows for a system 3.3V source
to be connected to separated circuitry inside the ISL6260
and ISL6260B, solely devoted to the CLK_EN# function. The
output is a 3.3V CMOS signal with 4mA of source and
sinking capability. This implementation removes the need for
an external pull-up resistor on this pin, and due to the normal
level of this signal being a low, removes the leakage path
from the 3.3V supply to ground through the pull-up resistor.
This reduces 3.3V supply current, that would occur under
normal operation with a pull-up resistor, and prolongs battery
life. The 3.3V supply should be decoupled to digital ground,
not to analog ground for noise immunity.
As mentioned in the “Theory of Operation” section of this
datasheet, CLK_EN# is logic level high at start-up until 20μs
after the system Vccp and Vcc_mch supplies are within
regulation, and the Vcc-core is in regulation at the Boot level.
Approximately 20μs after these voltages are within
19
Die sensing is the ability of the controller to regulate the
Core output voltage at a remotely sensed point. This allows
the Voltage Regulator to compensate for various resistive
drops in the power path and insure that the voltage seen at
the CPU die is the correct level independent of load current.
The VSEN and RTN pins of the ISL6260 and ISL6260B are
connected to Kelvin sense leads at the die of the processor
through the processor socket. These signal names are
Vcc_sense and Vss_sense respectively. This allows the
Voltage Regulator to tightly control the processor voltage at
the die, independent of layout inconsistencies and drops.
This Kelvin sense technique provides for extremely tight load
line regulation.
These traces should be laid out as noise sensitive traces.
For optimum load line regulation performance, the traces
connecting these two pins to the Kelvin sense leads of the
processor must be laid out away from rapidly rising voltage
nodes (switching nodes) and other noisy traces. To achieve
optimum performance, place common mode and differential
mode RC filters to analog ground on VSEN and RTN as
shown in Figure 42. The filter resistors should be in order of
10Ω so that they do not interact with the 50kΩ input
resistance of the differential amplifier.
Due to the fact that the voltage feedback to the switching
regulator is sensed at the processor die, there exists the
potential of an overvoltage due to an open circuited
feedback signal, should the regulator be operated without
the processor installed. Due to this fact, we recommend the
use of the Ropn1 and Ropn2 connected to Vout and ground
as shown in Figure 42. These resistors will provide voltage
feedback in the event that the system is powered up without
a processor installed. These resistors are typically 100Ω.
Setting the Switching Frequency - FSET
The R3 modulator scheme is not a fixed frequency PWM
architecture. The switching frequency can increase during
the application of a load to improve transient performance.
However, 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 35. A resistor connected between the VW
and COMP pins of the ISL6260 and ISL6260B adjusts the
switching window, and therefore adjusts the switching
frequency. The Rfset resistor that sets up the switching
frequency of the converter operating in CCM can be
FN9162.1
January 3, 2006
ISL6260, ISL6260B
determined using the following relationship, where Rfset is in
kΩ and the switching period is in μs.
(EQ. 4)
Rfset ( kΩ ) = ( Period ( μs ) – 0.29 ) × 2.33
In discontinuous conduction mode, (DCM), the ISL6260,
ISL6260B runs in period stretching mode. It should be noted
that the switching frequency in the Electric Table is tested
with the error amplifier output or Comp pin voltage at 2V.
When Comp pin voltage is lower, the switching frequency will
not be at the tested value.
Voltage Regulator Thermal Throttling
lntel® IMVP-6® technology supports thermal throttling of the
processor to prevent catastrophic thermal damage to the
voltage regulator. The ISL6260 and ISL6260B feature a
thermal monitor which senses the voltage change across an
externally placed negative temperature coefficient (NTC)
thermistor, see Figure 41. Proper selection and placement of
the NTC thermistor allows for detection of a designated
temperature rise by the system.
Figure 41 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 from 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.
54µA
6µA
+
1.20V
Therefore, proper NTC thermistor has to be chosen such
that 2.56K resistor change will be corresponding to required
temperature hysteresis. Regular external resistor may need
to be in series with NTC resistors to meet the threshold
voltage values.
The following is an example.
For Panasonic NTC with B = 4700, its resistance will drop to
0.03322 of its nominal at 105°C, and drop to 0.03956 of its
nominal at 100 C°. If the requirement for the temperature
hysteresis is (105-100) C°, the required resistance of NTC
will be:
2 . 56 K Ω
( 0 . 03956 − 0 . 03322
)
= 404 K Ω
Therefore a larger value thermistor, such as 470 K NTC
should be used.
At 105°C, 470K NTC resistance becomes
(0.03322*470K) = 15.6K. With 60µA on NTC pin, the voltage
is only (15.6K*60µA) = 0.937V. This value is much lower
than the threshold voltage of 1.18V. Therefore, a resistor is
needed to be in series with the NTC. The required resistance
can be calculated by:
4.02K is a standard resistor value. Therefore, the NTC
branch should have a 470K NTC and 4.02K resistor in
series. The part number for the NTC thermistor is
ERTJ0EV474J. It is a 0402 package. NTC thermistor will be
placed in the hot spot of the board. A thermistor in an 0402
package costs less than in an 0603 package.
-
Rs
= 2 . 56 K
VR_TT#
SW1
RNTC
1 .2 V
1 . 18 V
−
54 μ A
60 μ A
1 . 18 V
− 15 . 6 K Ω = 4 . 06 K Ω
60 uA
NTC
+
VNTC
-
eventually go up. If NTC voltage increases to 1.20V, the
comparator will then be able to flip back. The external
resistance difference in these two conditions is:
SW2
1.18V
INTERNAL TO
ISL6260
FIGURE 41. CIRCUITRY ASSOCIATED WITH THE THERMAL
THROTTLING FEATURE OF THE ISL6260
When temperature increases, the NTC resistor on NTC pin
decreases. The voltage on NTC pin decreases to a level
lower than 1.18V. The comparator changes polarity and
turns SW1 off and throws SW2 to 1.20V. This pulls VR_TT#
low and sends the signal to start thermal throttle. There is a
6µA current reduction on NTC pin and 20mV voltage
increase on threshold voltage of the comparator in this state.
The VR_TT# signal will be used to change the CPU
operation and decrease the power consumption. When the
temperature goes down, the NTC thermistor voltage will
20
FN9162.1
January 3, 2006
ISL6260, ISL6260B
IS E N 1
IS E N 2
10uA
OCSET
RTN
VSEN
VO'
V D IF F
RS2
VSUM
Rpar
+
-
RO1
VO'
L2
R L2
DCR
+ V d c r2 RO2
C L2
VO'
Ip h a s e 3
Rntc
1
IS E N 1
IS E N 2
Cn
+
DROOP
+
-
Rdrp2
Σ
1
DFB
Rdrp1
In te r n a l to
IS L 6 2 6 0
C L1
R L1
Ip h a s e 2
VSUM
Rseries
+
DROOP
-
L3
+
V d cr3
RS3
R L3
0 .0 1 u F
IS E N 3
10
0 .2 2 u F
Ropn1
VC C _S EN S E
VSS _S EN S E
Ropn2
Vout
-
DCR
VSUM
VO'
-
DCR
VSUM
VO'
VSUM
+
V d c r1
+
RS1
R OCSET
+
OC
L1
IS E N 3
IS E N 2
IS E N 1
Ip h a s e 1
IS E N 3
C L3
RO3
C b u lk
VO'
to V o u t
ESR
T o P ro ce ss o r
S o c k e t K e lv in
C o n n e c tio n s
FIGURE 42. EQUIVALENT MODEL FOR DROOP AND DIE SENSING USING DCR SENSING
Static Mode of Operation - Static Droop using DCR
Sensing
As previously mentioned, the ISL6260 and ISL6260B have
an internal differential amplifier which provides for extremely
accurate voltage regulation at the die of the processor. The
load line regulation is also very accurate, and the process of
selecting the components for the appropriate load line droop
is explained here.
Figure 43 shows the simplified model of the droop circuitry.
Essentially one resistor can replace the RO resistors of each
phase and one RS resistor can replace the RS resistors of
each phase. The total DCR drop due to load current can be
replaced by a DC source, the value of which is given by
Equation 5.
Iout × DCR
Vdcr EQV = ------------------------------N
(EQ. 5)
For DCR sensing, the process of compensation for DCR
resistance variation to achieve the desired load line droop
has several steps and is somewhat iterative. Refer to
Figure 42.
where N is the number of channels designed for Active
operation. N = 3 for this example. Another simplification can
be done by reducing the NTC network comprised of Rntc,
Rseries and Rparallel, given in Figure 43, to a single resistor
given as Rn.
In Figure 42 we show a 3 phase solution using DCR
sensing. There are two resistors around the inductor of each
phase. These are labeled RS and RO. These resistors are
used to arrive at the DC voltage drop across each inductor.
Each inductor will have a certain level of DC current flowing
through it, this current when multiplied by the DCR of the
inductor creates a small DC level of voltage. When this
voltage is summed with the other channels DC voltages, the
total DC load current can be derived.
The first step in droop load line compensation is to adjust
Rn, ROEQV and RSEQV such that sufficient droop voltage
exists even at light loads between the VSUM and VO’ nodes.
We recognize that these components form a voltage divider.
As a rule of thumb we start with the voltage drop across the
Rn network, VN, to be 0.57 x Vdcr. This ratio provides for a
fairly reasonable amount of light load signal from which to
arrive at droop.
RO is typically 5 to 10Ω. This resistor is used to tie the
outputs of all channels together and thus create a summed
average of the local CORE voltage output. RS is determined
through an understanding of both the DC and transient load
currents. This value will be covered in the next section.
First we calculate the equivalent NTC network resistance,
Rn. Typical values that provide good performance are,
Rseries = 3.57K_1%, Rpar = 4.53K_1% and Rntc = 10kΩ
NTC, ERT-J1VR103J from Panasonic. Rn is then given by
Equation 6.
However, it is important to keep in mind that the output of
each of these RS resistors are tied together to create the
VSUM voltage node. With both the outputs of RO and RS
tied together, the simplified model for the droop circuit can
be derived. This is presented in Figure 43.
21
( Rseries + Rntc ) × Rpar
Rn = -------------------------------------------------------------------- = 3.4kΩ
Rseries + Rntc + Rpar
(EQ. 6)
In our second step we calculate the series resistance from
each phase to the Vsum node, labeled RS1, RS2 and RS3
in Figure 42.
FN9162.1
January 3, 2006
ISL6260, ISL6260B
10uA
OCSET
+
OC
RS EQV =
VSUM
+
DROOP
-
Vdcr EQV = Iout ×
DROOP
RTN
VDIFF
VSEN
VO'
Cn
+
1 -
+
+
Rdrp1
Σ
+
1 -
+
DFB
Rdrp2
Internal to
ISL6260
VSUM
RS
N
VN
Rn =
DCR
N
(Rntc + Rseries ) × Rpar
(Rntc + Rseries ) + Rpar
VO'
RO EQV =
RO
N
FIGURE 43. EQUIVALENT MODEL FOR DROOP AND DIE SENSING USING DCR SENSING
We do this using the assumption that we desire
approximately a 0.57 gain from the DCR voltage, Vdcr, to the
Rn network. We call this gain, G1.
(EQ. 7)
G1 = 0.57
After simplification, then RSEQV is given by the following
equation:
1
RS EQV = ⎛ -------- – 1⎞ Rn = 2.56kΩ
⎝ G1
⎠
(EQ. 8)
The individual resistors from each phase to the VSUM node,
labeled RS1, RS2 and RS3 in Figure 42, are then given by
Equation 9, where N is 3, for the number of channels in
active operation.
RS = N × RS EQV = 7.69kΩ
(EQ. 9)
Choosing RS = 7.68k_1% is a good choice. Once we know
the attenuation of the RS and RN network, we can then
determine the Droop amplifier Gain required to achieve the
load line. Setting Rdrp1 = 1k_1%, then Rdrp2 is can be
found using Equation 10.
N × Rdroop
Rdrp2 = ⎛ -------------------------------- – 1⎞ × Rdrp1
⎝ DCR × G1
⎠
(EQ. 10)
Setting N = 3 for 3 channel operation, Droop Impedance
(Rdroop) = 0.0021 (V/A) as per the Intel IMVP-6
specification, DCR = 0.0012Ω typical, Rdrp1 = 1kΩ and the
attenuation gain (G1) = 0.57, Rdrp2 is then
3 × 0.0021
Rdrp2 = ⎛ ------------------------------------ – 1⎞ × 1K = 8.21kΩ
⎝ 0.0012 × 0.57
⎠
22
(EQ. 11)
Rdrp2 is selected to be a 8.25k_1% resistor. Note, we
choose to ignore the RO resistors because they do not add
significant error.
These values are extremely sensitive to layout and coupling
factor of the NTC to the inductor. As only one NTC is
required in this application, this NTC should be placed as
close to the Channel 1 inductor as possible and PCB traces
sensing the inductor voltage should be go directly to the
inductor pads.
Once the board has been laid out, some adjustments may
be required to adjust the full load droop voltage. This is fairly
easy and can be accomplished by allowing the system to
achieve thermal equilibrium at full load, and then adjusting
Rdrp2 to obtain the appropriate load line slope.
To see whether the NTC has compensated the temperature
change of the DCR, the user can apply full load current and
wait for the thermal steady state and see how much the
output voltage will deviate from the initial voltage reading. A
good compensation can limit the drift to 2mV. If the output
voltage is decreasing with temperature increase, that ratio
between the NTC thermistor value and the rest of the
resistor divider network has to be increased. The user
should follow the component values and layout of NTC on
evaluation board as much as possible to minimize
engineering time.
The 2.1mV/A load line should be adjusted by Rdrp2 based on
maximum current steps, not based on small current steps like
10A, as the droop gain might vary slightly between each 10A
steps. Basically, if the max current is 40A, the required droop
voltage is 84mV. The user should have 40A load current on
the converter and look for 84mV droop. If the droop voltage is
FN9162.1
January 3, 2006
ISL6260, ISL6260B
less than 84mV, for example, 80mV. The new value will be
calculated by:
Rdrp 2 _ new
=
84 mV
( Rdrp 1 + Rdrp 2 ) − Rdrp 1
80 mV
For the best accuracy, the effective resistance on the DFB
and VSUM pins should be identical so that the bias current
of the droop amplifier does not cause an offset voltage. In
the example above, the resistance on the DFB pin is Rdrp1
in parallel with Rdrop2, that is, 1K in parallel with 8.21K or
890Ω. The resistance on the VSUM pin is Rn in parallel with
RSeqv or 3.4K in parallel with 2.56K or 1460Ω. The
mismatch in the effective resistances is 1460-890 = 570Ω.
Do not let the mismatch get larger than 600Ω. To reduce the
mismatch, multiply both Rdrp1 and Rdrp2 by the appropriate
factor. The appropriate factor in the example is
1460/890 = 1.64.
Dynamic Mode of Operation - Dynamic Droop
using DCR Sensing
Droop is very important for load transient performance. If the
system is not compensated correctly, the output voltage
could sag excessively upon load application and potentially
create a system failure. The output voltage could also take a
long period of time to settle to its final value. This could be
problematic if a load dump were to occur during this time.
This situation would cause the output voltage to rise above
the no load setpoint of the converter and could potentially
damage the CPU.
The L/DCR time constant of the inductor must be matched to
the Rn*Cn time constant as shown in the following equation:
⎛ Rn × RS EQV⎞
L
-⎟ × Cn
------------- = ⎜ ---------------------------------DCR
⎝ Rn + RS EQV⎠
(EQ. 12)
Solving for Cn we now have the following equation:
L
------------DCR
Cn = ----------------------------------------⎛ Rn × RS EQV⎞
⎜ -----------------------------------⎟
⎝ Rn + RS EQV⎠
(EQ. 13)
Note, RO was neglected. As long as the inductor time
constant matches the Cn, Rn and Rs time constants as
given above, the transient performance will be optimum. As
in the Static Droop Case, this process may require a slight
adjustment to correct for layout inconsistencies. For the
example of L = 0.5μH, Cn is calculated below.
0.5μH
-----------------0.0012
Cn = ------------------------------------------------- = 28.5nF
3.4kΩ × 2.56kΩ⎞
⎛ -----------------------------------------⎝ 3.4kΩ + 2.56kΩ⎠
(EQ. 14)
The value of this capacitor is selected to be 27nF. As the
inductors tend to have 20% to 30% tolerances, this cap
generally will be tuned on the board by examining the
transient voltage. If the output voltage transient has an initial
dip, lower than the voltage required by the load line, and
slowly increases back to the steady state, the cap is too
23
small and vice versa. It is better to have the cap value a little
bigger to cover the tolerance of the inductor to prevent the
output voltage from going lower than the spec. This cap
needs to be a high grade cap like X7R with low tolerance.
There is another consideration in order to achieve better
time constant match mentioned above. The NPO/COG
(class-I) capacitors have only 5% tolerance and a very good
thermal characteristics. But those caps are only available in
small capacitance values. In order to use such capacitors,
the resistors and thermistors surrounding the droop voltage
sensing and droop amplifier has to be resized up to 10X to
reduce the capacitance by 10X. But attention has to be paid
in balancing the impedance of droop amplifier in this case.
Dynamic Mode of Operation - Compensation
Parameters
Considering the voltage regulator as a black box with a
voltage source controlled by VID and a series impedance, in
order to achieve the 2.1mV/A load line, the impedance
needs to be 2.1mΩ. The compensation design has to ensure
the output impedance of the converter be lower than 2.1mΩ.
There is a mathematical calculation file available to the user.
The power stage parameters such as L and Cs are needed
as the input to calculate the compensation component
values. Attention has be paid to the input resistor to the FB
pin. Too high of a resistor will cause an error to the output
voltage regulation because of bias current flowing in the FB
pin. It is better to keep this resistor below 3K when using this
file.
Static Mode of Operation - Current Balance using
DCR or Discrete Resistor Current Sensing
Current Balance is achieved in the ISL6260 and ISL6260B
through the matching of the voltages present on the ISEN
pins. The ISL6260 and ISL6260B adjust the duty cycles of
each phase to maintain equal potentials on the ISEN pins.
RL and CL around each inductor, or around each discrete
current resistor, are used to create a rather large time
constant such that the ISEN voltages have minimal ripple
voltage and represent the DC current flowing through each
channel’s inductor. For optimum performance, RL is chosen
to be 10kΩ and CL is selected to be 0.22µF. When discrete
resistor sensing is used, a capacitor of 10nF should be
placed in parallel with RL to properly compensate the current
balance circuit.
ISL6260 and ISL6260B uses RC filter to sense the average
voltage on phase node and forces the average voltage on
the phase node to be equal for current balance. Even though
the ISL6260, ISL6260B forces the ISEN voltages to be
almost equal, the inductor currents will not be exactly equal.
Take DCR current sensing as example, two errors have to
be added to find the total current imbalance. 1) Mismatch of
DCR: If the DCR has a 5% tolerance then the resistors could
mismatch by 10% worst case. If each phase is carrying 20A
then the phase currents mismatch by 20A*10% = 2A. 2)
Mismatch of phase voltages/offset voltage of ISEN pins. The
FN9162.1
January 3, 2006
ISL6260, ISL6260B
phase voltages are within 2mV of each other by current
balance circuit. The error current that results is given by
2mV/DCR. If DCR = 1mΩ then the error is 2A.
In the above example, the two errors add to 4A. For a two
phase DC/DC, the currents would be 22A in one phase and
18A in the other phase. In the above analysis, the current
balance can be calculated with 2A/20A = 10%. This is the
worst case calculation, for example, the actual tolerance of
two 10% DCRs is 10%*sqrt(2) = 7%.
current sensing resistors, and therefore is populated with a
47pF capacitor.
The Rs values in the previous section, Rs = 7.68k_1% are
sufficient for this approach.
Now, the input to the Droop amplifier is the Vrsense voltage.
This voltage is given by the following equation:
Rsense
Vrsense = ---------------------- × Iout
N
(EQ. 15)
There are provisions to correct the current imbalance due to
layout or to purposely divert current to certain phase for better
thermal management. Customer can put a resistor in parallel
with the current sensing capacitor on the phase of interest in
order to purposely increase the current in that phase. But it is
highly recommended for symmetrical layout.
The gain of the Droop amplifier, G2, must be adjusted for the
ratio of the Rsense to Droop impedance, Rdroop. We use
the following equation:
In the case the PC board trace resistance from the inductor
to the microprocessor are not the same on all three phases,
the current will not be balanced. On the phases that have too
much trace resistance a resistor can be added in parallel
with the ISEN capacitor that will correct for the poor layout.
But it is highly recommended for symmetrical layout.
Assuming N = 3, Rdroop = 0.0021(V/A) as per the Intel
IMVP-6 specification, Rsense = 0.001Ω, we obtain G2 = 6.3.
An estimate of the value of the resistor is:
Rdroop
G2 = ---------------------- × N
Rsense
(EQ. 16)
The values of Rdrp1 and Rdrp2 are selected to satisfy two
requirements. First, the ratio of Rdrp2 and Rdrp1 determine
the gain G2 = (Rdrp2/Rdrp1)+1. Second, the parallel
combination of Rdrp1 and Rdrp2 should equal the parallel
combination of the Rs resistors. Combining these
requirements gives:
Rtweak = Risen* [2*Rdcr - (Rtrace - Rmin)]/[2(Rtrace - Rmin)]
where Risen is the resistance from the phase node to the
ISEN pin; usually 10kΩ. Rdcr is the DCR resistance of the
inductor. Rtrace is the trace resistance from the inductor to
the microprocessor on the phase that needs to be tweaked.
It should be measured with a good microΩ meter. Rmin is
the trace resistance from the inductor to the microproccessor
on the phase with the least resistance.
For example, if the PC board trace on one phase is 0.5mΩ
and on another trace is 0.3mΩ; and if the DCR is 1.2mΩ;
then the tweaking resistor is Rtweak = 10kΩ * [1.2*2 (0.5-0.3)]/[2*(0.5-0.3)] = 55kΩ.
Droop using Discrete Resistor Sensing - Static/
Dynamic Mode of Operation
When choosing current sense resistor, not only the tolerance
of the resistance is important, but also the TCR. And its
combined tolerance at a wide temperature range should be
calculated.
Figure 44 shows the equivalent circuit of a discrete current
sense approach. Figure 36 shows a more detailed
schematic of this approach. Droop is solved the same way
as the DCR sensing approach with a few slight
modifications.
First, there is no NTC required for thermal compensation,
therefore, the Rn resistor network in the previous section is
not required. Secondly, there is no time constant matching
required, therefore, the Cn component is not matched to the
L/DCR time constant, but this component does indeed
provide noise immunity, especially due to the ESL of the
24
Rdrp1 = G2/(G2-1) * Rs/N
Rdrp2 = (G2-1) * Rdrp1
In the example above, Rs = 7.68K, N = 3, and G2 = 6.3 so
Rdrp 3K and Rdrp2 is 15.8kΩ.
These values are extremely sensitive to layout. Once the
board has been laid out, some tweaking may be required to
adjust the full load Droop. This is fairly easy and can be
accomplished by allowing the system to achieve thermal
equilibrium at full load, and then adjusting Rdrp2 to obtain
the desired Droop value.
Fault Protection - Overcurrent Fault Setting
As previously described, the overcurrent protection of the
ISL6260, ISL6260B is related to the Droop voltage.
Previously we have calculated that the Droop Voltage =
ILoad * Rdroop, where Rdroop is the load line slope
specified as 0.0021 (V/A) in the Intel IMVP-6 specification.
Knowing this relationship, the overcurrent protection
threshold can be set up as a voltage Droop level. Knowing
this voltage droop level, one can program in the appropriate
drop across the Roc resistor. This voltage drop will be
referred to as Voc. Once the droop voltage is greater than
Voc, the PWM drives will turn off and PGOOD will go low.
The selection of Roc is given below in Equation 17.
Assuming we desire an overcurrent trip level, Ioc, of 55A,
and knowing from the Intel Specification that the load line
FN9162.1
January 3, 2006
+
ISL6260, ISL6260B
10uA
Roc
+
VSUM
+
DROOP
-
+
VDIFF
+
1 -
DROOP
+
1 -
RTN
+
VSEN
VO'
Rdrp1
Σ
+
RS
N
DFB
Rdrp2
Internal to
ISL6260
RS EQV =
VSUM
Cn
OC
-
Voc
OCSET
Vrsense EQV = Iout ×
Rsense
N
VN
VO'
ROEQV =
RO
N
FIGURE 44. EQUIVALENT MODEL FOR DROOP AND DIE SENSING USING DISCRETE RESISTOR SENSING
slope, Rdroop is 0.0021 (V/A), we can then calculate for Roc
as shown in Equation 17.
Ioc × Rdroop
55 × 0.0021
Roc = ------------------------------------- = ------------------------------- = 11.5KΩ
10μA
10x10 – 6
(EQ. 17)
Note, if the droop load line slope is not -0.0021 (V/A) in the
application, the overcurrent setpoint will differ from
predicted.
A capacitor may be added in parallel with Roc to improve
noise rejection but the Roc*capacitor time constant cannot
exceed 20µs. Do not remove Roc if overcurrent protection is
not desired. The maximum Roc is 30K.
25
FN9162.1
January 3, 2006
ISL6260, ISL6260B
Quad Flat No-Lead Plastic Package (QFN)
Micro Lead Frame Plastic Package (MLFP)
2X
9
MILLIMETERS
D/2
D1
D1/2
2X
N
6
INDEX
AREA
40 LEAD QUAD FLAT NO-LEAD PLASTIC PACKAGE
(COMPLIANT TO JEDEC MO-220VJJD-2 ISSUE C)
0.15 C A
D
A
L40.6x6
0.15 C B
SYMBOL
MIN
NOMINAL
MAX
NOTES
A
0.80
0.90
1.00
-
A1
-
-
0.05
-
A2
-
-
1.00
A3
1
2
3
E1/2
E/2
E1
b
D2
0.15 C B
0.15 C A
4X
B
TOP VIEW
0
A
C
0.08 C
SEATING PLANE
A1
A3
SIDE VIEW
9
5
NX b
0.10 M C A B
4X P
D2
(DATUM B)
8
7
NX k
D2
2 N
4X P
-
4.10
9
4.25
6.00 BSC
-
5.75 BSC
9
3.95
4.10
4.25
(Ne-1)Xe
REF.
E2
-
k
0.25
-
-
-
L
0.30
0.40
0.50
8
L1
-
-
0.15
10
N
40
2
Nd
10
3
Ne
10
3
P
-
-
0.60
9
θ
-
-
12
9
NOTES:
1. Dimensioning and tolerancing conform to ASME Y14.5-1994.
7
E2/2
NX L
N e
8
2. N is the number of terminals.
8
3. Nd and Ne refer to the number of terminals on each D and E.
4. All dimensions are in millimeters. Angles are in degrees.
9
CORNER
OPTION 4X
(Nd-1)Xe
REF.
7, 8
0.50 BSC
Rev. 1 10/02
2
3
6
INDEX
AREA
7, 8
E
1
(DATUM A)
5, 8
5.75 BSC
3.95
e
/ / 0.10 C
0.30
E1
E2
A2
0.23
9
6.00 BSC
D1
9
2X
2X
0.18
D
E
9
0.20 REF
BOTTOM VIEW
5. Dimension b applies to the metallized terminal and is measured
between 0.15mm and 0.30mm from the terminal tip.
6. The configuration of the pin #1 identifier is optional, but must be
located within the zone indicated. The pin #1 identifier may be
either a mold or mark feature.
A1
NX b
5
7. Dimensions D2 and E2 are for the exposed pads which provide
improved electrical and thermal performance.
SECTION "C-C"
C
L
L1
10
8. Nominal dimensions are provided to assist with PCB Land Pattern
Design efforts, see Intersil Technical Brief TB389.
C
L
L
L1
e
10
L
e
C C
TERMINAL TIP
FOR ODD TERMINAL/SIDE
9. Features and dimensions A2, A3, D1, E1, P & θ are present when
Anvil singulation method is used and not present for saw
singulation.
10. Depending on the method of lead termination at the edge of the
package, a maximum 0.15mm pull back (L1) maybe present. L
minus L1 to be equal to or greater than 0.3mm.
FOR EVEN TERMINAL/SIDE
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26
FN9162.1
January 3, 2006