ISL70003SEH Datasheet

DATASHEET
Radiation Hardened and SEE Hardened 3V to 13.2V, 6A
Buck Regulator
ISL70003SEH
Features
The ISL70003SEH is a radiation and SEE hardened
synchronous buck regulator capable of operating over an
input voltage range of 3.0V to 13.2V. With integrated
MOSFETs, this highly efficient single chip power solution
provides a tightly regulated output voltage that is externally
adjustable from 0.6V to ~90% of the input voltage.
Continuous output load current capability is 6A for
TJ ≤+125°C and 3A for TJ ≤ +150°C.
• Acceptance tested to 50krad(Si) (LDR) wafer-by-wafer
The ISL70003SEH uses voltage mode control architecture
with feed-forward and switches at a selectable frequency of
500kHz or 300kHz. Loop compensation is externally
adjustable to allow for an optimum balance between stability
and output dynamic performance. The internal synchronous
power switches are optimized for high efficiency and
excellent thermal performance.
The chip features two logic-level disable inputs that can be
used to inhibit pulses on the phase (LXx) pins in order to
maximize efficiency based on the load current. The
ISL70003SEH also supports DDR applications and contains a
buffer amplifier for generating the VREF voltage.
High integration, best in class radiation performance and a
feature filled design make the ISL70003SEH an ideal choice
to power many of todays small form factor applications.
Applications
• FPGA, CPLD, DSP, CPU core and I/O supply voltages
• DDR memory supply voltages
• Low-voltage, high-density distributed power systems
Related Literature
• AN1897, ISL70003SEHEV1Z Evaluation Board
• ±1% reference voltage over line, temperature and radiation
• Integrated MOSFETs 31mΩPFET/21mΩ NFET
- 95% peak efficiency
• Externally adjustable loop compensation
• Supports DDR applications (VTT tracks VDDQ/2)
- Buffer amplifier for generating VREF voltage
- 3A current sinking capability
• Grounded lid eliminates charge build up
• IMON pin for output current monitoring
• Adjustable analog soft-start
• Diode emulation for increased efficiency at light loads
• 500kHz or 300kHz operating frequency synch wording
• Monotonic start-up into prebiased load
• Full military temperature range operation
- TA = -55°C to +125°C
- TJ = -55°C to +150°C
• Radiation tolerance
- High dose rate (50-300rad(Si)/s). . . . . . . . . . . 100krad(Si)
- Low dose rate (0.01rad(Si)/s) . . . . . . . . . . . . 100krad(Si)*
* Limit established by characterization.
• SEE hardness
- SEB and SEL LETTH . . . . . . . . . . . . . . . . 86.4MeV•cm2/mg
- SET at LET 86.4MeV•cm2/mg . . . . . . . . . . . < ±3% ΔVOUT
- SEFI LETTH . . . . . . . . . . . . . . . . . . . . . . . . . 60MeV•cm2/mg
• Electrically screened to DLA SMD 5962-14203
• AN1915, ISL70003SEH iSim:PE Model
• AN1913, Single Event Effects Testing of the ISL70003SEH,
3V to 13.2V, 6A Synchronous Buck Regulator
EFFICIENCY (%)
• AN1924, Total Dose Testing of the ISL70003SEH Radiation
Hardened Point Of Load Regulator
FIGURE 1. POWER DISTRIBUTION SOLUTION FOR RAD HARD LOW
POWER FPGA’s
February 6, 2015
FN8604.4
1
100
95
90
85
80
75
70
65
60
55
50
5V
9V
2.5V
3.3V
0
1
2
3
4
LOAD CURRENT (A)
5
6
FIGURE 2. EFFICIENCY vs LOAD, VIN = 12V, fSW = 300kHz
ALL OUTPUTS ACTIVE
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774 | Copyright Intersil Americas LLC 2013, 2014, 2015. All Rights Reserved
Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries.
All other trademarks mentioned are the property of their respective owners.
ISL70003SEH
Table of Contents
Functional Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Pin Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Pin Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Typical Application Schematics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Thermal Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Recommended Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Typical Performance Curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Power Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Enable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Power on Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Soft -Start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Power-Good . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Fault Monitoring and Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Undervoltage and Overvoltage Monitor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Undervoltage Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Overcurrent Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Voltage Feed-forward . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Switching Frequency Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Output Voltage Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Setting the Overcurrent Protection Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Disabling the Power Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
IMON Current Sense Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Diode Emulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
DDR Application. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
DDR Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Derating Current Capability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
General Design Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Output Inductor Selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Output Capacitor Selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Input Capacitor Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Feedback Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Modulator Break Frequency Equations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Compensation Break Frequency Equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
PCB Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
PCB Plane Allocation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
PCB Component Placement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
LX Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Thermal Management for Ceramic Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Lead Strain Relief . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Heatsink Mounting Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Heatsink Electrical Potential . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Heatsink Mounting Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Package Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Weight of Packaged Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Lid Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Die Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Die Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Interface Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Layout Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Step and Repeat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Revision History. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
About Intersil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Package Outline Drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Submit Document Feedback
2
FN8604.4
February 6, 2015
ISL70003SEH
VREF_OUTS
VREFD
VREFA
EN
Functional Block Diagram
POR and ON/OFF
POR_VIN
AVDD
LINEAR
REGULATORs
CONTROL
DVDD
SEL1
SEL2
RAMP
RT/CT
IMON
CURRENT
SENSE
PVINx
SOFT
START
SS_CAP
NI
COMP
EA
FB
PWM
CONTROL
LOGIC
GATE
DRIVE
LXx
VERR
SGND
VOUT
MONITOR
PGOOD
PGNDx
PWM
REFERENCE
0.6V
REF
OCSETA
OVERCURRENT
ADJUST
OCSETB
BUFINBUFIN+
BUFOUT
DDR VREF
BUFFER AMP
BUF
DGND
PGNDx
SYNC
FSEL
AGND
DE
Ordering Information
ORDERING SMD
NUMBER (Note 1)
PART NUMBER
(Note 2)
TEMPERATURE
RANGE (°C)
PACKAGE
(RoHS Compliant)
PACKAGE
DRAWING
5962R1420301VXC
ISL70003SEHVF
-55 to +125
64 Ld CQFP
R64.A
5962R1420301VYC
ISL70003SEHVFE
-55 to +125
64 Ld CQFP with Heatsink
R64.C
5962R1420301V9A
ISL70003SEHVX
-55 to +125
Die
ISL70003SEHF/PROTO
ISL70003SEHF/PROTO
-55 to +125
64 Ld CQFP
R64.A
ISL70003SEHFE/PROTO
ISL70003SEHFE/PROTO
-55 to +125
64 Ld CQFP with Heatsink
R64.C
ISL70003SEHX/SAMPLE
ISL70003SEHX/SAMPLE
-55 to +125
Die
ISL70003SEHEV1Z
ISL70003SEHEV1Z
Evaluation Board
NOTES:
1. Specifications for Rad Hard QML devices are controlled by the Defense Logistics Agency Land and Maritime (DLA). The SMD numbers listed in the
“Ordering Information” table on page 2 must be used when ordering.
2. These Intersil Pb-free Hermetic packaged products employ 100% Au plate - e4 termination finish, which is RoHS compliant and compatible with both
SnPb and Pb-free soldering operations.
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3
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February 6, 2015
ISL70003SEH
Pin Configuration
PVIN3
NC/HS*
IMON
SGND
PVIN2
LX2
PGND2
PGND1
LX1
PVIN1
OCSETA
OCSETB
BUFIN+
FOR PIN 1 LOCATION
BUFIN-
REF
BOTTOM SIDE DETAIL
BUFOUT
ISL70003SEH
(64 LD CQFP)
TOP VIEW
1
64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49
48
FB
2
47
PGND3
VERR
3
46
PGND4
POR_VIN
4
45
LX4
VREFA
5
44
PVIN4
AVDD
6
AGND
7
DGND
8
VREF_OUTS
9
PRODUCT BRAND
NAME AREA
NI
1 (NI)
(Note 3)
43
PVIN5
42
LX5
41
PGND5
40
PGND6
39
LX6
38
PVIN6
DVDD
10
VREFD
11
ENABLE
12
37
PVIN7
RT/CT
13
36
LX7
FSEL
14
35
PGND7
SYNC
15
34
PGND8
HEATSINK OUTLINE *
NOTE:
3. The ESD triangular mark is indicative of pin #1 location. It is part of the device marking and is
placed on the lid in the quadrant where pin #1 is located.
4
LX8
PVIN8
DE
SEL2
SEL1
PVIN9
LX9
PGND9
PGND10
LX10
PVIN10
PGOOD
GND
GND
GND
GND
16
33
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
GND
SS_CAP
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LX3
* Indicates heatsink package R64.C
FN8604.4
February 6, 2015
ISL70003SEH
Pin Descriptions
PIN NUMBER
PIN NAME
ESD CIRCUIT
DESCRIPTION
1
NI
1
This pin is the non-inverting input to the internal error amplifier. Connect this pin to the REF pin for
typical applications or the BUFOUT pin for DDR memory power applications.
2
FB
1
This pin is the inverting input to the internal error amplifier. An external type III compensation network
should be connected between this pin and the VERR pin. The connection between the FB resistor divider
and the output inductor should be a Kelvin connection to optimize performance.
3
VERR
1
This pin is the output of the internal error amplifier. An external compensation network should be
connected between this pin and the FB pin.
4
POR_VIN
1
This pin is the power-on reset input to the IC. This is a comparator-type input with a rising threshold of
0.6V and programmable hysteresis. Driving this pin above 0.6V enables the IC. Bypass this pin to AGND
with a 10nF ceramic capacitor to mitigate SEE.
5
VREFA
3
This pin is the output of the internal linear regulator and the bias supply input to the internal analog
control circuitry. Locally filter this pin to AGND using a 0.47µF ceramic capacitor as close as possible to
the IC.
6
AVDD
5
This pin provides the supply for internal linear regulator of the ISL70003SEH. The supply to AVDD
should be locally bypassed using a ceramic capacitor. Tie AVDD to the PVINx pins.
7
AGND
1, 3
This pin is the analog ground associated with the internal analog control circuitry. Connect this pin
directly to the PCB ground plane.
8
DGND
2, 4
This pin is the ground associated with the internal digital control circuitry. Connect this pin directly to
the PCB ground plane.
9
VREF_OUTS
4
This pin is the output of the internal linear regulator and the supply input to the internal reference
circuit. Locally filter this pin to AGND using a 0.47µF ceramic capacitor as close as possible to the IC.
10
DVDD
6
This pin provides the supply for the internal linear regulator of the ISL70003SEH. The supply to DVDD
should be locally bypassed using a ceramic capacitor. Tie DVDD to the PVINx pin.
11
VREFD
4
This pin is the output of the internal linear regulator and the bias supply input to the internal digital
control circuitry. Locally filter this pin to DGND using a 0.47µF ceramic capacitor as close as possible
to the IC.
12
ENABLE
6
This pin is a logic-level enable input. Pulling this pin low powers down the chip by placing it into a very
low power sleep mode.
13
RT/CT
6
A resistor to VIN and a capacitor to GND provide feed-forward to keep a constant modulator gain of 4.8
as VIN varies.
14
FSEL
2
This pin is the oscillator frequency select input. Tie this pin to 5V to select a 300kHz nominal oscillator
frequency. Tie this pin to the PCB ground plane to select a 500kHz nominal oscillator frequency.
15
SYNC
2
This pin is the frequency synchronization input to the IC. This pin should be tied to GND to free-run from
the internal oscillator or connected to an external clock for external frequency synchronization.
16
SS_CAP
2
This pin is the soft-start input. Connect a ceramic capacitor from this pin to the PCB ground plane to set
the soft-start output ramp time in accordance with Equation 1:
t SS = C SS  V REF  I SS
(EQ. 1)
where:
tSS = soft-start output ramp time
CSS = soft-start capacitance
VREF = reference voltage (0.6V typical)
ISS = soft-start charging current (23µA typical)
Soft-start time is adjustable from approximately 2ms to 200ms. The range of the soft-start capacitor
should be 82nF to 8.2µF, inclusive.
17, 18, 19, 20, 21
GND
2
Connect this pin to the PCB ground plane.
22
PGOOD
6
This pin is the power-good output. This pin is an open-drain logic output that is pulled to DGND when
the output voltage is outside a ±11% typical regulation window. This pin can be pulled up to any voltage
from 0V to 13.2V, independent of the supply voltage. A nominal 1kΩ to 10kΩ pull-up resistor is
recommended. Bypass this pin to the PCB ground plane with a 10nF ceramic capacitor to mitigate SEE.
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5
FN8604.4
February 6, 2015
ISL70003SEH
Pin Descriptions (Continued)
PIN NUMBER
PIN NAME
ESD CIRCUIT
DESCRIPTION
23, 28, 32, 37,
38, 43, 44, 49,
53, 58
PVINx
7
These pins are the power supply inputs to the corresponding internal power blocks. These pins must be
connected to a common power supply rail, which should fall in the range of 3V to 13.2V. Bypass these
pins directly to PGNDx with ceramic capacitors located as close as possible to the IC. When sinking
current or at a no load condition, the inductor valley current will be negative. During any time when the
inductor valley current is negative and the ISL70003 is exposed to a heavy ion environment, the abs
max PVIN voltage must be ≤13.7V.
29
SEL1
2
This pin is a logic-level disable (high) input working in conjunction with SEL2. These pins form a two-bit
logic input that set the number of active power blocks. This allows the ISL70003SEH current capability
to be tailored to the load current level the application requires and achieve the highest possible
efficiency.
30
SEL2
2
This pin is a logic-level disable input. Pulling this pin high inhibits pulses on the LXx outputs. See
description of Pin 29, SEL1, for more information.
31
DE
2
The DE pin enables or disables Diode Emulation. When it is HIGH, diode emulation is allowed.
Otherwise, continuous conduction mode is forced.
24, 27, 33, 36,
39, 42, 45, 48,
54, 57
LXx
50
NC/HS
N/A
This is a No Connect pin that is not connected to anything internally. In the R64.C package (heatsink
option) this pin is electrically connected to the heatsink on the underside of the package. Connect this
pin and/or the heatsink to a thermal plane.
51
IMON
1
IMON is a current source output that is proportional to the sensed current through the regulator. If not
used it is recommended to tie IMON to VREFA. It is also acceptable to tie IMON to GND through a
resistor.
52
SGND
1
This pin is connected to an internal metal trace that serves as a noise shield. Connect this pin to the
PCB ground plane.
25, 26, 34, 35,
40, 41, 46, 47,
55, 56
PGNDx
7
These pins are the power grounds associated with the corresponding internal power blocks. Connect
these pins directly to the PCB ground plane. These pins should also connect to the negative terminals
of the input and output capacitors. The package lid is internally connected to PGNDx
59
OCSETA
3
This pin is the redundant output overcurrent set input. Connect a resistor from this pin to the PCB
ground plane to set the output overcurrent threshold.
60
OCSETB
3
This pin is the primary output overcurrent set input. Connect a resistor from this pin to the PCB ground
plane to set the output overcurrent threshold.
61
BUFIN+
1
This pin is the input to the internal unity gain buffer amplifier. For DDR memory power applications,
connect the VTT voltage to this pin.
62
BUFIN-
1
This pin is the inverting input to the buffer amplifier. For DDR memory power applications, connect
BUFOUT to this pin. Bypass this pin to the PCB ground plane with a 0.1µF ceramic capacitor.
63
BUFOUT
3
This pin is the output of the buffer amplifier. In DDR power applications, connect this pin to the
reference input of the DDR memory. The buffer needs a minimum of 1.0µF load capacitor for stability.
64
REF
1
This pin is the output of the internal reference voltage. Bypass this pin to the PCB ground plane with a
220nF ceramic capacitor located as close as possible to the IC. The bypass capacitor is needed to
mitigate SEE.
These pins are the switch node connections to the internal power blocks and should be connected to
the output filter inductor. Internally, these pins are connected to the synchronous MOSFET power
switches.
VREFA
VREFD
PIN #
PIN #
AGND
CIRCUIT 1
DGND
CIRCUIT 2
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6
PIN #
7V
CLAMP
AGND
CIRCUIT 3
PIN #
7V
CLAMP
DGND
CIRCUIT 4
AVDD
12V
CLAMP
AGND
CIRCUIT 5
PIN #
12V
CLAMP
DGND
CIRCUIT 6
PVINx
12V
CLAMP
PGNDx
CIRCUIT 7
FN8604.4
February 6, 2015
ISL70003SEH
Typical Application Schematics
VIN = 12V
100k
22k
51
10k
0.47µF
0.47µF
0.47µF
16
357
ISL70003SEH
SYNC
SS
10nF
22
24
27
33
36
39
42
45
48
54
57
1nF
VOUT = 3.3V
+
10
150µF
x3
1µF
1nF
17
18
19
20
21
0.22µF
6.8nF
4.02k
6.8nF
60
52
7
8
25
26
34
35
40
41
46
47
55
56
2.7nF
4.02k
SGND
AGND
DGND
PGND10
PGND9
PGND8
PGND7
PGND6
PGND5
PGND4
PGND3
PGND2
PGND1
OCB
FSEL
SEL1
SEL2
DE
NC
51.1k
14
29
30
31
50
12pF
2 FB
3
VERR
1
NI
64
REF
TDI
TPGM
TDO
TSTRIM
TCLK
5.49k
3.3µH
OCA 59
0.1µF
25k
LX10
LX9
LX8
LX7
LX6
LX5
LX4
LX3
LX2
LX1
5
VREFA
9
11 VREFOUTS
VREFD
15
PGOOD
PORVIN
PGOOD
IMON
3k
10nF
4
23
28
32
37
38
43
44
49
53
58
6
10
12
7.15k
PVIN10
PVIN9
PVIN8
PVIN7
PVIN6
PVIN5
PVIN4
PVIN3
PVIN2
PVIN1
AVDD
DVDD
VIMON
EN
RT/CT 13
370pF
51k
61
62
63
5 x 1µF
4x100µF
BUFIN+
BUFINBUFOUT
+
FIGURE 3. ISL70003SEH SINGLE UNIT OPERATION
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FN8604.4
February 6, 2015
ISL70003SEH
Typical Application Schematics (Continued)
VIN = 5V
25k
5 x 1µF
22k
51
PORVIN
10k
0.47µF
0.47µF
15
16
715
25k
LX10
LX9
LX8
LX7
LX6
LX5
LX4
LX3
LX2
LX1
24
27
33
36
39
42
45
48
54
57
1.5µH
VDDQ = 2.5V
+
10
1µF
3 x 150µF
1nF
4nF
0.33µF
6.8nF
4.02k
6.8nF
60
SGND
AGND
DGND
PGND10
PGND9
PGND8
PGND7
PGND6
PGND5
PGND4
PGND3
PGND2
PGND1
OCB
4.02k
52
7
8
25
26
34
35
40
41
46
47
55
56
31.2k
FB
VERR
NI
REF
FSEL
SEL1
SEL2
DE
NC
2
3
1
64
10nF
OCA 59
17
TDI
18
TPGM
19
TDO
20
TSTRIM
21
TCLK
68pF
SYNC
SS
0.1µF
1nF
7.87k
ISL70003SEH
14
29
30
31
50
0.47µF
5
VREFA
9
11 VREFOUTS
VREFD
PGOOD
22
PGOOD
IMON
3k
10nF
4
23
28
32
37
38
43
44
49
53
58
6
10
4k
PVIN10
PVIN9
PVIN8
PVIN7
PVIN6
PVIN5
PVIN4
PVIN3
PVIN2
PVIN1
AVDD
DVDD
VIMON
12
RT/CT 13
370pF
EN
4x100µF
BUFIN+ 61
62
BUFIN63
BUFOUT
+
VREF = 1.25V
1µF
25k
51
0.22µF
REF
0.47µF
0.47µF
0.47µF
IMON
5
9 VREFA
11 VREFOUTS
VREFD
15
16
400
25k
SYNC
4
PVIN10
PVIN9
PVIN8
PVIN7
PVIN6
PVIN5
PVIN4
PVIN3
PVIN2
PVIN1
AVDD
DVDD
PGOOD
10k
ISL70003SEH
SS
PGOOD
LX10
LX9
LX8
LX7
LX6
LX5
LX4
LX3
LX2
LX1
10nF
22
24
27
33
36
39
42
45
48
54
57
2.2µH
VTT = 1.25V
2 FB
3
VERR
25k
1µF
1nF
8.2k
6.8nF
8.2k
6.8nF
SGND
AGND
DGND
PGND10
PGND9
PGND8
PGND7
PGND6
PGND5
PGND4
PGND3
PGND2
PGND1
FSEL
SEL1
SEL2
DE
NC
60
52
7
8
25
26
34
35
40
41
46
47
55
56
17
18
19
20
21
15nF
OCB
NI
TDI
TPGM
TDO
TSTRIM
TCLK
1
14
29
30
31
50
22.9k
3 x 150µF
OCA 59
0.1µF
82pF
+
10
1.6nF
22.9k
3k
10nF
PORVIN
64
4k
23
28
32
37
38
43
44
49
53
58
6
10
RT/CT 13
370pF
12
22k
EN
5 x 1µF
4x100µF
61
BUFIN+
62
BUFIN63
BUFOUT
+
7.87k
FIGURE 4. ISL70003SEH DDR MEMORY POWER SOLUTION
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FN8604.4
February 6, 2015
ISL70003SEH
Absolute Maximum Ratings
Thermal Information
LXx, PVINx . . . . . . . . . . . . . . . . . . . . . . . . . . . .PGNDx - 0.3V to PGNDx + 16V
LXx, PVINx (Note 4). . . . . . . . . . . . . . . . . . . PGNDx - 0.3V to PGNDx + 14.7V
LXx, PVINx (Note 5). . . . . . . . . . . . . . . . . . . PGNDx - 0.3V to PGNDx + 13.7V
AVDD - AGND, DVDD - DGND . . . . . . . . . . . . . . . . . . . . . . . . . . PVINx to -0.3V
VREFA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GNDA - 0.3V to GNDA + 5.5V
VREFD, VREF_OUTS . . . . . . . . . . . . . . . . . . . . .GNDD - 0.3V to GNDD + 5.5V
Signal Pins (Note 10) . . . . . . . . . . . . . . . . . . . GNDA - 0.3V to VREFA + 0.3V
Digital Control Pins (Note 11) . . . . . . . . . . . . .GNDD - 0.3V to VREFD+ 0.3V
SS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .DGND - 0.3V to DGND + 2.5V
PGOOD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GNDD - 0.3V to DVDD
RTCT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GNDD - 0.3V to DVDD
ESD Rating
Human Body Model (Tested per MIL-STD-883 TM3015.7) . . . . . . . . 2kV
Machine Model (Tested per JESD22-A115-A) . . . . . . . . . . . . . . . . . 200V
Charge Device Model (Tested per JESD22-C101D) . . . . . . . . . . . . 750V
Thermal Resistance (Typical)
JA (°C/W) JC (°C/W)
CQFP Package R64.A (Notes 6, 7) . . . . . . .
34
1.5
CQFP Package R64.C (Notes 8, 9) . . . . . . .
17
0.7
Maximum Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . .+150°C
Storage Temperature Range. . . . . . . . . . . . . . . . . . . . . . . .-65°C to +150°C
Pb-Free Reflow Profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . see TB493
Recommended Operating Conditions
Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-55°C to +125°C
PVINx, AVDD, DVDD . . . . . . . . . . . . . . . . . . . . . . . . 3.3V ±10% to 12V ±10%
CAUTION: Do not operate at or near the maximum ratings listed for extended periods of time. Exposure to such conditions may adversely impact product
reliability and result in failures not covered by warranty.
NOTES:
4. For operation in a heavy ion environment at LET = 86.4 MeV•cm2/mg at 125°C (TC) and sourcing 7A load current.
5. For operation in a heavy ion environment at LET = 86.4 MeV•cm2/mg at 125°C (TC) with any negative inductor current to sinking -4A load current.
6. JA is measured with the component mounted on a high effective thermal conductivity test board in free air. See Tech Brief TB379 for details.
7. For JC, the “case temp” location is the center of the package underside.
8. JA is measured in free air with the component mounted on a high effective thermal conductivity test board with “direct attach” features. See Tech
Brief TB379.
9. For JC, the “case temp” location is the center of the exposed metal heatsink on the package underside.
10. POR_VIN, FB, NI, VERR, OCSETA, OCSETB, BUFOUT, BUFIN-, BUFIN+, IMON and REF pins.
11. FSEL, EN, SYNC, SEL1, SEL2, and DE pins.
Electrical Specifications
Unless otherwise noted, VIN = AVDD = DVDD = PVINx = EN = 3V - 13.2V; GND = AGND = DGND = PGNDx =
GNDx = 0V; POR_VIN = FB = 0.65V; SYNC = LXx = Open Circuit; PGOOD is pulled up to VREFD with a 3k resistor; REF is bypassed to GND with a 220nF
capacitor; SS is bypassed to GND with a 100nF capacitor; IOUT = 0A; TA = TJ = +25°C. (Note 4). Boldface limits apply across the operating temperature
range, -55°C to +125°C; over a total ionizing dose of 100krad(Si) with exposure at a high dose rate of 50 - 300rad(Si)/s; or over a total ionizing dose of
50krad(Si) with exposure at a low dose rate of <10mrad(Si)/s.
PARAMETER
MIN
(Note 15)
TYP
MAX
(Note 15)
UNITS
PVINx = 13.2V, FSEL = 1
80
125
mA
PVINx = 13.2V, FSEL = 0
80
125
mA
PVINx = 3.0V, FSEL = 1
30
60
mA
PVINx = 3.0V, FSEL = 0
30
60
mA
PVINx = 13.2V, SEL1 = SEL2 = GND, FSEL = 1
20
30
mA
PVINx = 13.2V, SEL1 = SEL2 = GND, FSEL = 0
20
30
mA
PVINx = 3.0V, SEL1 = SEL2 = GND, FSEL = 1
10
15
mA
PVINx = 3.0V, SEL1 = SEL2 = GND, FSEL = 0
10
15
mA
PVINx = 13.2V, EN = GND
1.5
3.0
mA
PVINx = 3.0V, EN = GND
0.4
1.0
mA
5.0
5.5
V
190
mA
TEST CONDITIONS
POWER SUPPLY
Operating Supply Current
Standby Supply Current
Shutdown Supply Current
LINEAR REGULATORS
Output Voltage
AVDD, DVDD = 13.2V
4.5
Current Limit
AVDD, DVDD = 13.2V
50
Submit Document Feedback
9
FN8604.4
February 6, 2015
ISL70003SEH
Electrical Specifications
Unless otherwise noted, VIN = AVDD = DVDD = PVINx = EN = 3V - 13.2V; GND = AGND = DGND = PGNDx =
GNDx = 0V; POR_VIN = FB = 0.65V; SYNC = LXx = Open Circuit; PGOOD is pulled up to VREFD with a 3k resistor; REF is bypassed to GND with a 220nF
capacitor; SS is bypassed to GND with a 100nF capacitor; IOUT = 0A; TA = TJ = +25°C. (Note 4). Boldface limits apply across the operating temperature
range, -55°C to +125°C; over a total ionizing dose of 100krad(Si) with exposure at a high dose rate of 50 - 300rad(Si)/s; or over a total ionizing dose of
50krad(Si) with exposure at a low dose rate of <10mrad(Si)/s. (Continued)
MIN
(Note 15)
TYP
MAX
(Note 15)
UNITS
POR Pin Input Voltage
0.56
0.6
0.64
V
POR Sink Current
9.6
12
14.4
µA
PARAMETER
TEST CONDITIONS
POWER-ON RESET
ENABLE
Enable VIH Voltage
2
V
Enable VIL Voltage
Enable (EN) Leakage
EN = 4.5V
1.0
0.8
V
10
µA
SELECT PHASE
SEL 1, 2 VIH Voltage
2
V
SEL 1, 2 VIL Voltage
SEL 1, 2 Leakage Current
SEL1, 2 = VREFD
0.8
V
1.0
10
µA
PWM CONTROL LOGIC
Switching Frequency
FSEL = 1
255
300
345
kHz
FSEL = 0
425
500
575
kHz
Minimum On Time
SS = GND (Note 14)
250
320
ns
Minimum On Time
(Note 14)
160
220
ns
Minimum Off Time
(Note 14)
200
270
ns
Modulator Gain (VIN /ΔVOSC)
RT = 22kΩ, CT = 370pF, FSEL = 0
5
V/V
RT = 36kΩ, CT = 370pF, FSEL = 1
4.8
V/V
External Synchronization Frequency Range FSEL = 1, PVINx = 3.0V
255
300
345
kHz
FSEL = 0, PVINx = 3.0V
425
500
575
kHz
SYNC VIH Voltage
2
V
SYNC VIL Voltage
Synchronization Input Leakage Current
SYNC = VREFD
0.8
V
1.0
4
µA
23
27
µA
3.0
6.0
Ω
SOFT-START
Soft-start Source Current
SS = GND
20
Soft-start Discharge ON-Resistance
Soft-start Discharge Time
(Note 14)
256
Clock Cycles
REFERENCE VOLTAGE
Reference Voltage Tolerance
VREF + Error Amplifier VIO
0.594
0.6
0.606
V
ERROR AMPLIFIER
DC Gain
(Note 14)
80
dB
Gain-bandwidth Product
(Note 14)
7
MHz
Maximum Output Voltage
VIN = 5.5V
4.2
V
Slew Rate
(Note 14)
8.5
V/µs
Feedback (FB) Input Leakage Current
VFB = 0.6V, PVINx = 13.2V
Offset Voltage (VIO)
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3.5
-3
10
0
250
nA
3
mV
FN8604.4
February 6, 2015
ISL70003SEH
Electrical Specifications
Unless otherwise noted, VIN = AVDD = DVDD = PVINx = EN = 3V - 13.2V; GND = AGND = DGND = PGNDx =
GNDx = 0V; POR_VIN = FB = 0.65V; SYNC = LXx = Open Circuit; PGOOD is pulled up to VREFD with a 3k resistor; REF is bypassed to GND with a 220nF
capacitor; SS is bypassed to GND with a 100nF capacitor; IOUT = 0A; TA = TJ = +25°C. (Note 4). Boldface limits apply across the operating temperature
range, -55°C to +125°C; over a total ionizing dose of 100krad(Si) with exposure at a high dose rate of 50 - 300rad(Si)/s; or over a total ionizing dose of
50krad(Si) with exposure at a low dose rate of <10mrad(Si)/s. (Continued)
MIN
(Note 15)
TYP
MAX
(Note 15)
UNITS
PVINx = 3.0V
170
420
700
mΩ
PVINx = 5.5V
120
310
600
mΩ
PVINx = 3.0V
90
240
455
mΩ
PVINx = 5.5V
60
210
425
mΩ
EN = LXx = GND, Single LXx Output
1
3
µA
EN = GND, LXx = PVINx, Single LXx Output
1
3
µA
PARAMETER
TEST CONDITIONS
POWER BLOCKS
Upper Device rDS(ON)
Lower Device rDS(ON)
LXx Output Leakage
Dead Time
Within a Single Power Block or between Power
Blocks (Note 14)
4
ns
POWER-GOOD SIGNAL
Rising Threshold
VFB as a % of VREF
107
111
115
%
Rising Hysteresis
VFB as a % of VREF
2
3.5
5
%
Falling Threshold
VFB as a % of VREF
85
89
93
%
Falling Hysteresis
VFB as a % of VREF
2
3.5
5
Power-good Drive
PVIN = 3V, PGOOD = 0.4V, EN = GND
Power-good Leakage
PVIN = PGOOD = 13.2V
7.2
%
mA
1
µA
PROTECTION FEATURES
Undervoltage Protection
Undervoltage Trip Threshold
VFB as a % of VREF, Test mode
71
75
79
%
Undervoltage Recovery Threshold
VFB as a % of VREF, Test mode
86
90
94
%
0.43
0.6
0.77
A/LX
Overcurrent Protection
Overcurrent Accuracy
ROCSETA, B = 6kΩ (IOC = 0.6A/LX) VIN = 12V
BUFFER AMPLIFIER
Gain Bandwidth Product
CL = 1µF, ISOURCE = 1mA, AV = 1, VOUT = 1.25V
(Note 14)
200
kHz
Source Current Capability
20
Sink Current Capability
Offset Voltage
mA
250
400
µA
-4
0
4
mV
145
215
300
ns
IMON CURRENT MONITOR
IMON Sense Time
IMON Output Current Gain
ILOAD = 1A/Power Stage, LXx Off Time >300ns
IMON Gain Accuracy
ILOAD = 1A/Power Stage, LXx Off Time >300ns
100
-14
µA/A
14
µA
NOTES:
12. Typical values shown are not guaranteed.
13. The 0A to 6A output current range may be reduced by Minimum LXx On Time and Minimum LXx Off Time specifications.
14. Limits established by characterization or analysis and are not production tested.
15. Parameters with MIN and/or MAX limits are 100% tested at -55°C, +25°C and +125°C, unless otherwise specified.
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FN8604.4
February 6, 2015
ISL70003SEH
Typical Performance Curves
Unless otherwise noted, VIN = 12V, VOUT = 3.3V, IOUT = 3A, fSW = 500kHz,
CIN = 4x 100µF + 5x1µF, LOUT = 3.3µH, COUT = 3x 150µF + 1µF, TA = +25°C, All outputs active.
100
95
95
90
90
85
85
EFFICIENCY (%)
EFFICIENCY (%)
100
9V
80
5V
75
2.5V
70
65
3.3V
60
75
2.5V
65
55
0
1
2
3
4
LOAD CURRENT (A)
5
50
6
0
1
FIGURE 5. EFFICIENCY vs LOAD, VIN = 12V, 300kHz
100
100
95
95
90
90
85
85
80
1.8V
75
1.5V
2.5V
1.2V
3.3V
70
65
80
55
2
3
4
5
50
6
0
1
2
3
4
LOAD CURRENT (A)
100
95
95
90
90
85
85
EFFICIENCY (%)
EFFICIENCY (%)
100
1.8V
1.2V
1.5V
2.5V
70
65
80
55
2
3
4
5
LOAD CURRENT (A)
FIGURE 9. EFFICIENCY vs LOAD, VIN = 3.3V, 300kHz
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12
6
2.5V
65
60
1
6
1.8V
1.2V
70
55
0
1.5V
75
60
50
5
FIGURE 8. EFFICIENCY vs LOAD, VIN = 5V, 500kHz
FIGURE 7. EFFICIENCY vs LOAD, VIN = 5V, 300kHz
75
3.3V
1.2V
LOAD CURRENT (A)
80
6
2.5V
65
60
1
5
1.5V
70
55
0
1.8V
75
60
50
2
3
4
LOAD CURRENT (A)
FIGURE 6. EFFICIENCY vs LOAD, VIN = 12V, 500kHz
EFFICIENCY (%)
EFFICIENCY (%)
3.3V
5V
70
60
55
50
9V
80
50
0
1
2
3
4
5
6
LOAD CURRENT (A)
FIGURE 10. EFFICIENCY vs LOAD, VIN = 3.3V, 500kHz
FN8604.4
February 6, 2015
ISL70003SEH
Typical Performance Curves
4.0
4.5
3.5
4.0
3.0
9V
2.5
5V
2.0
1.5
1.0
1
5V
2.5
2.0
3.3V
1.5
2.5V
0.5
2.5V
0
3.0
1.0
3.3V
0.5
0.0
9V
3.5
POWER LOSS (W)
POWER LOSS (W)
Unless otherwise noted, VIN = 12V, VOUT = 3.3V, IOUT = 3A, fSW = 500kHz,
CIN = 4x 100µF + 5x1µF, LOUT = 3.3µH, COUT = 3x 150µF + 1µF, TA = +25°C, All outputs active. (Continued)
2
3
4
LOAD CURRENT (A)
5
0.0
6
0
2
6
3.3V
3.3V
POWER LOSS (W)
2.5
2.0
2.5V
1.5
1.5V
1.8V
1.0
0.5
2.5V
2.0
1.8V
1.5
1.5V
1.0
0.5
1.2V
1.2V
0
1
2
3
4
5
0.0
6
0
1
2
3
4
5
6
LOAD CURRENT (A)
LOAD CURRENT (A)
FIGURE 14. POWER LOSS, VIN = 5V, 500kHz
FIGURE 13. POWER LOSS, VIN = 5V, 300kHz
3.0
3.5
1.2V
2.5
3.0
1.8V
2.0
1.5
POWER LOSS (W)
POWER LOSS (W)
5
3.0
2.5
1.5V
1.0
1.2V
0.5
0.0
4
FIGURE 12. POWER LOSS, VIN = 12V, 500kHz
3.0
0.0
3
LOAD CURRENT (A)
FIGURE 11. POWER LOSS, VIN = 12V, 300kHz
POWER LOSS (W)
1
2.5V
2.5
1.8V
2.0
1.5
1.5V
1.0
0.5
0
1
2
3
4
5
LOAD CURRENT (A)
FIGURE 15. POWER LOSS, VIN = 3.3V, 300kHz
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13
6
0.0
1.2V
0
1
2
3
4
5
6
LOAD CURRENT (A)
FIGURE 16. POWER LOSS, VIN = 3.3V, 500kHz
FN8604.4
February 6, 2015
ISL70003SEH
Typical Performance Curves
3.35
1.818
3.34
1.812
OUTPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
Unless otherwise noted, VIN = 12V, VOUT = 3.3V, IOUT = 3A, fSW = 500kHz,
CIN = 4x 100µF + 5x1µF, LOUT = 3.3µH, COUT = 3x 150µF + 1µF, TA = +25°C, All outputs active. (Continued)
3.33
3.32
3.31
3.30
1.806
1.800
1.794
1.788
3.29
3.28
0
1
2
3
4
5
1.782
2
6
4
6
8
10
INPUT VOLTAGE (V)
LOAD CURRENT (A)
606
604
604
REFERENCE VOLTAGE (mV)
REFERENCE VOLTAGE (mV)
606
PVIN = 13.2V
600
PVIN = 3V
598
596
594
-60
-40
-20
0
20
40
60
80
100
120
-55°C
602
600
598
596
594
2
140
4
6
8
10
12
14
INPUT VOLTAGE (V)
FIGURE 19. REFERENCE VOLTAGE vs TEMPERATURE
FIGURE 20. REFERENCE VOLTAGE vs VIN
6.00
545
SWITCHING FREQUENCY (kHz)
500kHz
5.75
MODULATOR GAIN (V/V)
+25°C
+125°C
TEMPERATURE (°C)
5.50
5.25
5.00
4.75
300kHz
4.50
4.25
4.00
14
FIGURE 18. LINE REGULATION, VOUT = 1.8V, LOAD = 3A
FIGURE 17. LOAD REGULATION
602
12
495
PVIN = 13.2V
PVIN = 3V
445
395
PVIN = 3V
345
295
PVIN = 13.2V
2
4
6
8
10
INPUT VOLTAGE (V)
FIGURE 21. MODULATOR GAIN vs VIN
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14
12
14
245
-60
-40
-20
0
20
40
60
80
100
120
140
TEMPERATURE (°C)
FIGURE 22. SWITCHING FREQUENCY vs TEMPERATURE
FN8604.4
February 6, 2015
ISL70003SEH
Typical Performance Curves
Unless otherwise noted, VIN = 12V, VOUT = 3.3V, IOUT = 3A, fSW = 500kHz,
CIN = 4x 100µF + 5x1µF, LOUT = 3.3µH, COUT = 3x 150µF + 1µF, TA = +25°C, All outputs active. (Continued)
ENABLE, 5V/DIV
ENABLE, 5V/DIV
LXx VOLTAGE, 5V/DIV
INDUCTOR CURRENT, 2A/DIV
OUTPUT VOLTAGE, 2V/DIV
OUTPUT VOLTAGE, 2V/DIV
PGOOD, 10V/DIV
FIGURE 23. MONOTONIC SOFT-START WITH NO LOAD, CCM
ENABLE, 5V/DIV
LXx VOLTAGE, 5V/DIV
LXx VOLTAGE, 5V/DIV
OUTPUT VOLTAGE, 2V/DIV
OUTPUT VOLTAGE, 2V/DIV
PGOOD, 10V/DIV
PGOOD, 10V/DIV
LXx VOLTAGE, 5V/DIV
INDUCTOR CURRENT, 1A/DIV
OUTPUT VOLTAGE, 20mV/DIV
FIGURE 27. STEADY STATE OPERATION NO LOAD, CCM
15
FIGURE 24. MONOTONIC SOFT-START WITH 6A LOAD, CCM
ENABLE, 5V/DIV
FIGURE 25. MONOTONIC SOFT-START WITH 1.5V PREBIASED LOAD
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PGOOD, 10V/DIV
FIGURE 26. MONOTONIC SOFT-START WITH NO LOAD, DEM
LXx VOLTAGE, 5V/DIV
INDUCTOR CURRENT, 2A/DIV
OUTPUT VOLTAGE, 20mV/DIV
FIGURE 28. STEADY STATE OPERATION FULL LOAD, CCM
FN8604.4
February 6, 2015
ISL70003SEH
Typical Performance Curves
Unless otherwise noted, VIN = 12V, VOUT = 3.3V, IOUT = 3A, fSW = 500kHz,
CIN = 4x 100µF + 5x1µF, LOUT = 3.3µH, COUT = 3x 150µF + 1µF, TA = +25°C, All outputs active. (Continued)
INDUCTOR CURRENT, 2A/DIV
LXx VOLTAGE, 5V/DIV
INDUCTOR CURRENT, 0.5A/DIV
OUTPUT VOLTAGE, 200mV/DIV
OUTPUT VOLTAGE, 20mV/DIV
FIGURE 29. DIODE EMULATION OPERATION, VOUT = 1.2V, 125mA LOAD
FIGURE 30. 6A LOAD TRANSIENT RESPONSE, DIODE EMULATION
INDUCTOR CURRENT, 2A/DIV
INDUCTOR CURRENT, 2A/DIV
OUTPUT VOLTAGE, 50mV/DIV
OUTPUT VOLTAGE, 50mV/DIV
FIGURE 31. 3A LOAD TRANSIENT RESPONSE
FIGURE 32. 6A LOAD TRANSIENT RESPONSE
LXx VOLTAGE, 5V/DIV
LXx VOLTAGE, 5V/DIV
INDUCTOR CURRENT, 10A/DIV
INDUCTOR CURRENT, 5A/DIV
OUTPUT VOLTAGE, 2V/DIV
OUTPUT VOLTAGE, 2V/DIV
SS VOLTAGE, 2V/DIV
PGOOD, 10V/DIV
FIGURE 33. OVERCURRENT RESPONSE
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FIGURE 34. HICCUP RESPONSE IN OCP
FN8604.4
February 6, 2015
ISL70003SEH
Functional Description
Initialization
The ISL70003SEH is a monolithic synchronous buck regulator IC
with integrated power MOSFETs. The device utilizes voltage-mode
control with feed-forward and switches at a nominal frequency of
500kHz or 300kHz. It is fabricated on a 0.6μm BiCMOS junction
isolated process optimized for power management applications.
With this chip and a handful of external components, a complete
synchronous buck DC/DC converter can be readily implemented.
The converter accepts an input voltage ranging from 3V to 13.2V
and provides a tightly regulated output voltage ranging from 0.6V
to ~90% of the input voltage at output currents ranging from 0A
to 6A. Typical applications include Point Of Load (POL) regulation
for FPGAs, CPLDs, DSPs, DDR memory and microprocessors.
The ISL70003SEH initializes based on the state of the EN input
and POR input. Successful initialization prompts a soft-start
interval and the regulator begins slowly ramping the output
voltage. Once the commanded output voltage is within the
proper window of operation, the power-good signal changes state
from low to high indicating proper regulator operation.
Power Blocks
PVIN1
LX1
PGND1
POWER BLOCK 1
POWER BLOCK 6
OCPB and IMON
PVIN6
LX6
PGND6
PVIN2
LX2
PGND2
POWER BLOCK 2
POWER BLOCK 7
PVIN7
LX7
PGND7
PVIN3
LX3
PGND3
POWER BLOCK 3
POWER BLOCK 8
PVIN8
LX8
PGND8
POWER BLOCK 9
PVIN9
LX9
PGND9
Enable
The EN pin accepts TTL/CMOS logic input as described in the
Electrical Specifications” table on page 9. When the voltage on
the EN pin exceeds its logic rising threshold, the controller
monitors the POR voltage before initiating the soft-start function
for the PWM regulator. When EN is pulled low, the device enters
shutdown mode and the supply current drops to a typical value of
1.5mA. All internal power devices are held in a high-impedance
state while in shutdown mode. Due to the internal 5V clamp, the
EN pin should be driven no higher than 5V or excessive leakage
current may be seen on the pin. In standalone applications the
EN pin may be tied to an input voltage >5V through a 50kΩ
resistor to minimize the current into the EN pin. The current
should not be allowed to exceed 160µA at any operating voltage.
VIN > 5.0V
PVINx
PVIN4
LX4
PGND4
PVIN5
LX5
PGND5
POWER BLOCK 4
POWER BLOCK 5
and OCPA
POWER BLOCK 10
PVIN10
LX10
PGND10
EN
+
Note: Shaded blocks indicate pilot current and current sensors.
FIGURE 35. POWER BLOCK DIAGRAM
R1
51kΩ
ENABLE
COMPARATOR
POR
LOGIC
-
VR
The power output stage of the regulator consists of ten power
blocks that are paralleled to provide full 6A output current
capability at TJ = +125°C. The block diagram in Figure 35 shows
a top level view of the individual power blocks.
SEL1 and SEL2 pins allow users to disable power blocks in order
to reduce switching losses in light load applications. Depending
on the state of these pins the ISL70003SEH can operate with 2,
4, or 10 active power blocks and also be placed in a sleep mode.
Each power block has a power supply input pin, PVINx, a phase
output pin, LXx and a power supply ground pin, PGNDx. All PVINx
pins must be connected to a common power supply rail and all
PGNDx pins must be connected to a common ground. LXx pins
should be connected to the output inductor based on the
required load current and the state of the SEL1, SEL2 pins, but
must include the LX5 and LX6 pins. The unused LXx pins should
be left unconnected.
Scaled pilot devices associated with power blocks 5 and 6
provide current feedback for overcurrent detection and the IMON
current monitor feature. Power blocks 5 and 6 must be
connected to the output inductor at all times for proper
operation.
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FIGURE 36. ENABLE TO VIN FOR >5.0 INPUT VOLTAGE
Power on Reset
After the EN input requirements are met, the ISL70003SEH
remains in shutdown until the voltage at the POR pin rises above
its threshold. The POR circuitry prevents the controller from
attempting to soft-start before sufficient bias is present at the
PVINx pins.
As shown in Figure 37 on page 18, the POR circuit features a
comparator type input. The POR circuit allows the level of the
input voltage to precisely gate the turn-on/turn-off of the
regulator. An internal IPOR current sink with a typical value of
12µA is only active when the voltage on the POR pin is below the
enable threshold so it can pull the POR pin low. As VIN rises, the
POR enable level is set by the resistor divider (R1 and R2) from
VIN and the internal sink current source, IPOR.
FN8604.4
February 6, 2015
ISL70003SEH
output load current does not exceed the overcurrent trip level of
the regulator.
VR = 0.6V
IPOR = 12µA
CPOR = 10nF
V REF
t SS = C SS  --------------I SS
VIN
PVINx
(EQ. 4)
V OUT
I INRUSH = C OUT  ---------------t
(EQ. 5)
SS
VIN
POR
COMPARATOR
R1
POR
+
-
POR
LOGIC
VR
CPOR
R2
The soft-start capacitor is immediately discharged by a 3.0Ω
resistor whenever POR conditions are not met or EN is pulled low.
The soft-start discharge time is equal to 256 clock cycles.
VOUT
VREF = 0.6V
ISS = 23µA
RD = 2.2Ω
RT
FB
IPOR
FIGURE 37. POR CIRCUIT
Equation 2 defines the relationship between the resistor divider,
sink current and POR rising level (VPORR).
R1
V PORR = V R  1 + ------- + I POR  R 1
R
RB
ERROR
AMPLIFIER
+
+
PWM
LOGIC
SS
NI
VREF
RD
ISS
(EQ. 2)
2
REF
VREF
Once the voltage at the POR pin reaches the enable threshold,
the IPOR current sink turns off.
With the part enabled and the IPOR current sink off, the falling level
(VPORF) is set by the resistor divider network and is defined by
Equation 3.
R1
V PORF = V R  1 + ------R2
(EQ. 3)
The difference between the POR rising and falling levels provides
adjustable hysteresis so that noise on VIN does not interfere with
the enabling or disabling of the regulator.
Soft -Start
The ISL70003SEH soft-start function uses an internal current
source and an external capacitor to reduce stresses and surge
current during start-up.
Once the POR and enable circuits are satisfied, the regulator
waits 32 clock cycles and then initiates a soft-start. Figure 38
shows that the soft-start circuit clamps the error amplifier
reference voltage to the voltage on an external soft-start
capacitor connected to the SS pin. The soft-start capacitor is
charged by an internal ISS current source. As the soft-start
capacitor is charged, the output voltage slowly ramps to the set
point determined by the reference voltage and the feedback
network. Once the voltage on the SS pin is equal to the internal
reference voltage, the soft-start interval is complete. The
soft-start output ramp interval is defined in Equation 4 and is
adjustable from approximately 2ms to 200ms. The value of the
soft-start capacitor, CSS, should range from 82nF to 8.2µF,
inclusive. The peak in-rush current can be computed from
Equation 5. The soft-start interval should be selected long
enough to insure that the peak in-rush current plus the peak
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CSS
18
CREF
FIGURE 38. SOFT-START CIRCUIT
Power-Good
A power-good indicator is the final step of initialization. After a
successful soft-start, the PGOOD pin releases and the voltage
rises with an external pull-up resistor. The power-good signal
transitions low immediately when the EN pin is pulled low.
The PGOOD pin is an open-drain logic output and can be pulled
up to any voltage from 0V to 13.2V. The pull-up resistor should
have a nominal value from 1kΩ to 10kΩ. The PGOOD pin should
be bypassed to DGND with a 10nF ceramic capacitor to mitigate
SEE.
Fault Monitoring and Protection
The ISL70003SEH actively monitors the output voltage and
current to detect fault conditions. Fault conditions trigger
protective measures to prevent damage to the regulator and the
external load device. One common power-good indication signal
is provided for linking to external system monitors. The
schematic in Figure 39 on page 19 outlines the interaction
between the fault monitors and the power-good signal.
Undervoltage and Overvoltage Monitor
The power-good pin (PGOOD) is an open-drain logic output which
indicates that the converter is operating properly and the output
voltage is within a set window. The undervoltage (UV) and
overvoltage (OV) comparators create the output voltage window.
The power-good circuitry monitors the FB pin and compares it to
the rising and falling thresholds shown in the “Electrical
FN8604.4
February 6, 2015
ISL70003SEH
Specifications” table on page 11. If the feedback voltage
exceeds the typical rising limit of 111% of the reference voltage,
the PGOOD pin pulls low. The PGOOD pin continues to pull low
until the feedback voltage falls to a typical of 107.5% of the
reference voltage. If the feedback voltage drops below a typical
of 89% of the reference voltage, the PGOOD pin pulls low. The
PGOOD pin continues to pull low until the feedback voltage rises
to a typical 92.5% of the reference voltage. The PGOOD pin then
releases and signals the return of the output voltage within the
power-good window
0.666V
PGOOD
ϭϬ
LOAD CURRENT, 5A/DIV
ϵ
+
OV
ϴ
-
ϳ
0A
ϲ
+
UV
0.534V
OUTPUT VOLTAGE, 1V/DIV
ϱ
FB
Upon detection of an overcurrent condition, the upper MOSFET
will be immediately turned off and will not be turned on again
until the next switching cycle. Upon detection of the initial
overcurrent condition, the overcurrent fault counter is set to 1. If,
on the subsequent cycle, another overcurrent condition is
detected, the OC fault counter will increment, however, if the
sampled current falls below the threshold the counter is reset. If
there are 4 sequential OC fault detections, the counter will
overflow and the regulator will be shutdown under an overcurrent
fault condition, pulling PGOOD low.
ϰ
COUNTER/
POR/ ON-OFF
CONTROL
0V
ϯ
-
ISEN
+
UVP
OCSETB
+
-
0.45V
FIGURE 1. OVERCURRENT BEHAVIOR IN HICCUP MODE
OCSETA
Undervoltage Protection
A hysteretic comparator monitors the FB pin of the regulator. The
feedback voltage is compared to an undervoltage threshold that
is a fixed percentage of the reference voltage, typically 75%.
Once the comparator trips, indicating a valid undervoltage
condition, an undervoltage counter increments. The counter is
reset if the feedback voltage rises back above the undervoltage
threshold plus a specified amount of hysteresis outlined in the
“Electrical Specifications” table on page 11. If there are 4
consecutive undervoltage detections the counter will overflow
and the undervoltage protection logic shuts down the regulator,
pulling PGOOD low.
After the regulator shuts down, it enters a delay interval,
approximately equivalent to 512 clock cycles plus 1 soft-start
intervals, allowing the device to cool. The undervoltage counter is
reset entering the delay interval. The protection logic initiates a
normal soft-start once the delay interval ends. If the output
successfully soft-starts, the power-good signal goes high and
normal operation continues. If undervoltage conditions continue
to exist during the soft-start interval, the undervoltage counter
must overflow before the regulator shuts down again. This hiccup
mode continues indefinitely until the output soft-starts
successfully.
Overcurrent Protection
A pilot device integrated into the PMOS transistor of Power Blocks
5 and 6 sample the current each cycle. This current feedback is
scaled and compared to an overcurrent threshold based on the
resistor value tied from pins OCSETA and OCSETB to AGND.
19
0V
Ϭ
5ms/DIV
FIGURE 39. POWER-GOOD AND PROTECTION CIRCUITRY
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ϭ
ISEN
OCP
+
SOFT-START VOLTAGE, 1V/DIV
Ϯ
OCP
After the regulator shuts down, it enters a delay interval, allowing
the device to cool. The delay interval is approximately equal to
512 clock cycles plus 1 soft-start intervals. The overcurrent
counter is reset entering the delay interval. The protection logic
initiates a normal soft-start once the delay interval ends. If the
output successfully soft-starts, the power-good signal goes high
and normal operation continues. If overcurrent conditions
continue to exist during the soft-start interval, the overcurrent
counter must overflow before the regulator shutdowns the output
again. This hiccup mode continues indefinitely until the output
soft-starts successfully (see Figure 1).
Application Information
Voltage Feed-forward
Feed-forward is used to maintain a constant modulator gain and
achieve optimum loop response over a wide input voltage range.
A resistor from PVINx to RTCT and a capacitor from RTCT to
PGNDx are used to adjust the amplitude of the sawtooth ramp
proportional to the input voltage. The capacitor value must be
chosen so that it is large enough for mitigation of single event
transients but low enough for the internal MOSFET device to pull
the pin to ground. The following table gives the recommended
values for RT and CT for a given switching frequency. These
values will achieve a constant modulator gain across the
complete input voltage range.
FSEL STATE
fSW (kHz)
RT (kΩ)
CT (pF)
MODULATOR
GAIN (TYP)
0
500
22
370
5
1
300
36
370
4.8
FN8604.4
February 6, 2015
ISL70003SEH
Switching Frequency Selection
There are a number of variables to consider when choosing the
switching frequency. A high switching frequency increases the
switching losses but may lead to a decrease in output filter size.
A lower switching frequency may increase efficiency but may
lead to more output voltage ripple and increased output filter
size.
On the ISL70003SEH the switching frequency is determined by
the state of the TTL/CMOS compatible FSEL pin. A logic low will
set the regulator to operate with a 500kHz switching frequency,
while a logic high sets a 300kHz switching frequency.
Synchronization
The ISL70003SEH can be synchronized to an external clock with
a frequency range of 500kHz ±15% or 300kHz ±15%, depending
on the state of the FSEL pin.
The SYNC pin accepts the external clock signal and the regulator
will be synchronized in phase with the external clock. During
start-up the regulator will use its internal oscillator to regulate
the output voltage. Once soft-start is complete and PGOOD is
released, the regulator will synchronize to the external clock
signal. This feature allows the ISL70003SEH regulator to be the
power source to the external components that will be providing
the external clock without the requirement that a signal must be
present at the SYNC pin before start-up.
R 1  0.6V
R 4 = -----------------------------------------V OUT – 0.6V
(EQ. 6)
If the output voltage desired is 0.6V, then R4 is left unpopulated.
Setting the Overcurrent Protection Level
The ISL70003SEH features dual redundancy in the overcurrent
detection circuitry, which helps avoid false overcurrent triggering
due to single event effects. Two external resistors from pins
OCSETA and OCSETB to AGND set the level of the over current
protection (OCP) trip point. The OCP circuit senses the peak
current across a pilot device not the average current so it is
important to determine the overcurrent trip point (IOCP) greater
than the maximum output continuous current (IMAX) plus half
the maximum inductor ripple current (ΔI).
Use Equation 7 to determine the inductor ripple current:
V IN – V OUT
I = --------------------------------  D
f SW  L
(EQ. 7)
Where fSW is the switching frequency, L is the output inductor
value and D is duty cycle. Once an IOCP value is chosen that
satisfies Equation 8:
I
I OCP  I MAX + ----2
(EQ. 8)
Equation 9 may be used to determine the value of ROCSETA and
ROCSETB with all 10 power blocks active.
Output Voltage Selection
36024
R OCSET  A B  = ---------------I OCP
LXx
LO
VOUT
CO
R1
ERROR
AMPLIFIER
+
VREF
FB
NI
R4
REF
CREF
FIGURE 40. OUTPUT VOLTAGE SELECTION
The output voltage of the regulator can be programmed via an
external resistor divider that is used to scale the output voltage
relative to the reference voltage. The reference voltage and the
non-inverting input to the error amplifier are not internally
connected, therefore, for standalone applications the REF pin
must be tied to the NI pin (see Figure 40). The REF pin should be
bypassed to AGND with a 220nF ceramic capacitor to mitigate
SEE. It should be noted that no current (sourcing or sinking) is
available from the REF pin.
The output voltage programming resistor, R4, will depend on the
value chosen for the feedback resistor R1 and the desired output
voltage of the regulator. The value for the feedback resistor is
typically between 5kΩ and 25kΩ.
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20
(EQ. 9)
The minimum value for ROCSET(A,B) is 2.94kΩ which is
equivalent to a 12.25A IOCP level.
Disabling the Power Blocks
The ISL70003SEH offers two TTL/CMOS compatible power block
select pins, SEL1 and SEL2, which form a two-bit logic input that
are used to turn off the internal power blocks. Depending on the
state of the SEL1 and SEL2 pins, the ISL70003SEH can operate
with 2, 4 or 10 power blocks on or have all the outputs in a
tr-state mode. This allows the designer to reduce switching
losses in low current applications, where all power blocks are not
needed to supply the load current. Table 1 on page 20 compares
the logic state of SEL1 and SEL2 with the current capability of the
regulator and the number of active LXx pins.
TABLE 1. LOGIC STATE COMPARISON
SEL2
STATE
SEL1
STATE
ACTIVE LXx PINS
LOAD CAPABILITY
(TJ = +125°C)
0
0
All
6A
0
1
5, 6, 7, 8
2.4A
1
0
5, 6
1.2A
1
1
None
N/A
With both SEL pins in a logic high state, the ISL70003SEH is in a
low power sleep mode where all outputs are tri-stated. Once the
FN8604.4
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ISL70003SEH
logic activates the power blocks, the regulator ramps the output
voltage to its set value within a soft-start interval, however, the
device no longer goes through the preinitialization phase.
Transitions between the number of active LXx pins through the
use of SEL1 and SEL2 should not be done while the part is
operating. On the fly transitions will cause glitches on the output
voltage which may exceed transient requirements. It is
recommended to place the ISL70003SEH in standby mode, by
pulling SEL1 and SEL2 HIGH, and then change the number of
active LXx pins.
The overcurrent trip point scales depending on the number of
active power blocks. Equation 10 may be used to determine the
value of ROCSETA and ROCSETB when less than 10 power blocks
are active:
3602.4  N
R OCSET  A B  = ----------------------------I OCP
VIMON VOLTAGE
200mV/DIV
INDUCTOR
CURRENT
2A/DIV
TIME (5µs/DIV)
FIGURE 41. IMON RESPONSE TO 6A LOAD STEP
(EQ. 10)
Where N is the number of active phases.
VIMON VOLTAGE
200mV/DIV
IMON Current Sense Output
The ISL70003SEH provides a current monitor function through
IMON. Current monitoring informs designers if down steam loads
are operating as expected. It is also useful in the prototype and
debug phase of the design and during normal operation to
measure the overall performance of a system. The IMON pin
outputs a high speed analog current source that is proportional
to the sensed peak current through the ISL70003SEH. In typical
applications, a resistor RIMON is connected to the IMON pin to
convert the sensed current to voltage, VIMON, which is
proportional to the peak current, as shown in Equation 11:
V IMON = 100  10
– 6 I SAMPLE  R IMON
 --------------------------------------------------N
TIME (5µs/DIV)
FIGURE 42. IMON RESPONSE TO 6A LOAD RELEASE
(EQ. 11)
where VIMON is the voltage at the IMON pin, RIMON is the resistor
between the IMON pin and AGND, ISAMPLE is the current through
the converter at the time IMON samples the current, and N is the
number of active power blocks. ISAMPLE may be calculated from
Equation 12.
t SAMPLE  f SW
I
I SAMPLE = I LOAD + ----- –  I  ------------------------------------------


1 – D
2
INDUCTOR
CURRENT
2A/DIV
(EQ. 12)
Where tSAMPLE is the time it takes the IMON circuitry to sample
the current (300ns, max.), ILOAD is the load current and ΔI is the
inductor peak-to-peak ripple current as calculated in Equation 7.
A small capacitor should be placed between the IMON pin and
AGND to reduce the noise impact and mitigate single event
transients. If this pin is not used, it is best connected to VREFA. It
is also acceptable to tie to GND through a resistor.
Figures 41 and 42 show the response of the IMON current
monitor due to a load step with a RIMON = 10kΩ and 100pF
ceramic capacitor in parallel.
It is important to note that if the on time of the lower NMOS FET
is shorter than the IMON current sense time (300ns max), the
IMON output is tri-stated after 4 consecutive failed sense
occurrences.
Diode Emulation
Diode Emulation (DE) allows for higher converter efficiency under
light load situations. In DE mode, the low-side MOSFET conducts
when the current is flowing from source to drain and does not
allow reverse current, emulating a diode. As shown in Figure 43,
when the LGATE signal is HIGH, the low-side MOSFET carries
current, creating negative voltage on the phase node due to the
voltage drop across the ON-resistance. When the DE pin is pulled
HIGH, the ISL70003SEH will be in diode emulation mode and
detect the zero current crossing of the inductor current and turn
off the lower MOSFET to prevent the inductor current from
reversing direction and creating unnecessary power loss. This
ensures that discontinuous conduction mode (DCM) is achieved.
Since diode emulation prevents the low-side MOSFET from
sinking current, no negative spike at the output is generated
during pre-biased startup when DE mode is active.
After a significantly fast load release transient, diode emulation
will not allow the converter to bring the output voltage back down
following the hump created by the inductor energy dump into the
output capacitor bank. The ISL70003SEH overcomes this issue
by monitoring the output of the error amplifier and allowing the
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21
FN8604.4
February 6, 2015
ISL70003SEH
low-side MOSFET to turn on and sink the necessary current
needed to properly regulate the output voltage. The same
mechanism allows the converter to properly regulate the output
voltage when starting into a prebiased condition where the
prebias level is greater than the desired output voltage.
DDR Configuration
VDDQ
ISL70003SEH 1/2
RT1
FB
RB1
LXx
VDDQ
UGATE
NI
-
VIN
PVINx
LO
LXx
+
VDDQ
CO1
REF
PGNDx
VREF
RT1
LGATE
ERROR
AMPLIFIER
RB1
ISL70003SEH 2/2
IL
VTT
FIGURE 43. DIODE EMULATION
The DE pin is not intended to actively change states while the
regulator is operating. If any part of the inductor current is below
zero and the DE pin changes state there will be a glitch on the
output voltage. However, if the state of the DE pin changes state
when the inductor current is positive, no change in the operation
of the regulator will be seen.
FB
RB2
VDDQ
R
R
DDR Application
High through put Double Data Rate (DDR) memory ICs are
replacing traditional memory ICs in space applications. A novel
feature associated with this type of memory are the referencing
and data bus termination techniques. These techniques employ
a reference voltage, VREF, that tracks the center point of VDDQ
and VSS voltages, and an additional VTT power source where all
terminating resistors are connected. Despite the additional
power source, the overall memory power consumption is reduced
compared to traditional termination.
The added power source has a cluster of requirements that
should be observed and considered. Due to the reduced
differential thresholds of DDR memory, the termination power
supply voltage, V TT, closely tracks VDDQ/2 voltage.
Another very important feature of the termination power supply
is the capability to operate at equal efficiency in sourcing and
sinking modes. The VTT supply regulates the output voltage with
the same degree of precision when current is flowing from the
supply to the load, and when the current is diverted back from
the load into the power supply.
The ISL70003SEH regulator possesses several important
enhancements that allow reconfiguration for DDR memory
applications. Two ISL70003SEH ICs will provide all three voltages
required in a DDR memory compliant system.
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NI
RT2
22
B+
B-
+
ERROR
AMPLIFIER
+
BUFFER
AMPLIFIER
VIN
PVINx
LXx
PGNDx
LO
VTT
CO2
OUTB
VREF
CO3
FIGURE 44. SIMPLIFIED DDR APPLICATION SCHEMATIC
In the DDR application presented in Figure 44, an independent
architecture is implemented to generate the voltages needed for
DDR memory applications. Consequently, both VDDQ and VTT are
derived independently from the main power source. The first
regulator supplies the 2.5V for the VDDQ voltage. The output
voltage is set by external dividers RT1 and RB1. The second
regulator generates the VTT rail typically = VDDQ/2. The resistor
divider network RT2 and RB2 are used to set the output voltage to
1.25V. The VDDQ rail has an additional voltage divider network
consisting of RT1 and RB1, the midpoint is connected to the
noninverting input pin of the V TT regulator’s error amplifier (NI),
effectively providing a tracking function for the V TT voltage.
The noninverting input of the buffer amplifier is connected to the
center point of the external R/R divider from the VDDQ output.
The output of the buffer is tied back to the inverting input for
unity gain configuration. The buffer output voltage serves as a
1.25V reference (VREF) for the DDR memory chips. Sourcing
capability of the buffer amplifier is 10mA typical (20mA max)
and needs a minimum of 1µF load capacitance for stability.
Diode emulation mode of operation must be disabled on the V TT
regulator to allow sinking capability. In the event both channels
are enabled simultaneously, the soft-start capacitor on the VDDQ
regulator should be two to three times larger than the soft-start
capacitor on the VTT regulator. This allows the VDDQ regulator
voltage to be the lowest input into the error amplifier of the VTT
regulator and dominate the soft-start ramp. However, if the VTT
regulator is enabled later than the VDDQ, the soft-start capacitor
can be any value based on design goals.
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ISL70003SEH
Each regulator has its own fault protections and must be
individually configured. All the sink current on the VTT regulator is
provided by the VDDQ rail, the overcurrent protection on the
VDDQ rail will limit the amount of current that the VTT rail will
sink.
When sinking current or at a no load condition, the inductor
valley current is negative, see Figure 27. During any time when
the inductor valley current is negative and the ISL70003 is
exposed to a heavy ion environment the abs max PVIN voltage
must be ≤13.7V, see Note 5 on page 9.
SEL1 and SEL2 may be tied together and used to place the VTT
regulator in sleep mode, common to DDR applications. The
outputs will be tri-stated, however the buffer amplifier is still
active and the VREF voltage will be present even if the V TT is in
sleep mode. When SEL1 and SEL2 are asserted low, the VTT
regulator will ramp up the voltage. The ramp is controlled and
timing is based on soft-start capacitor value.
Refer to Figure 4 on page 8 for complete DDR power solution
typical application circuit schematic.
Derating Current Capability
Most space programs issue specific derating guidelines for parts,
but these guidelines take the pedigree of the part into account.
For instance, a device built to MIL-PRF-38535, such as the
ISL70003SEH, is already heavily derated from a current density
standpoint. However, a mil-temp or commercial IC that is
up-screened for use in space applications may need additional
current derating to ensure reliable operation because it was not
built to the same standards as the ISL70003SEH.
General Design Guide
This design guide is intended to provide a high-level explanation
of the steps necessary to design the power stage and feedback
compensation network of a single phase power converter. It is
assumed that the reader is familiar with many of the basic skills
and techniques in switch mode power supply design. In addition
to this guide, Intersil provides an evaluation board that includes
schematic, bills of materials and board layout.
Output Inductor Selection
The output inductor is selected to minimize the converter’s
response time to a load transient and meet steady state output
voltage ripple requirements. The inductor value determines the
converter’s inductor ripple current and the output voltage ripple
is a function of the inductor ripple current. The output voltage
ripple and the inductor ripple current are approximated by using
Equation 13:
V IN – V OUT V OUT
I = --------------------------------------------  ---------------f SW  L
V IN
V OUT = I  ESR
(EQ. 13)
Increasing the value of inductance reduces the ripple current and
output voltage ripple. However, the large inductance values
reduce the converter’s response time to a load transient.
One of the parameters limiting the converter’s response to a
load transient is the time required to change the inductor
current. The response time is the time required to slew the
inductor current from an initial current value to the transient
current level. During this interval the difference between the
inductor current and the transient current level must be
supplied by the output capacitor. Minimizing the response time
can minimize the output capacitance required.
The response time to a transient is different for the application of
load and the removal of load. Equation 14, gives the approximate
response time interval for application and removal of a transient
load.
tRISE =
FIGURE 45. CURRENT vs TEMPERATURE
Figure 45 shows the maximum average output current of the
ISL70003SEH with respect to junction temperature. These plots
take into account the worst-case current share mismatch in the
power blocks and the current density requirement of
MIL-PRF-38535 (< 2 x 105 A/cm2). The plot clearly shows that
the ISL70003SEH can handle 7A at +150°C from a worst-case
current density standpoint, but the part is rated to 3A. Therefore,
no further current derating of the ISL70003SEH is needed.
L x ITRAN
VIN - VOUT
tFALL =
L x ITRAN
VOUT
(EQ. 14)
Where ITRAN is the transient load current step, tRISE is the
response time to the application of load, and tFALL is the
response time to the removal of load. The worst case response
time can be either at the application or removal of load. Be sure
to check both Equations 13 and 14 at the minimum and
maximum output levels for the worst case response time.
Output Capacitor Selection
An output capacitor is required to filter the inductor current and
supply the load transient current. The filtering requirements are a
function of the switching frequency and the ripple current. The
load transient requirements are a function of the slew rate (di/dt)
and the magnitude of the transient load current. These
requirements are generally met with a mix of capacitors and
careful layout.
High-frequency capacitors initially supply the transient and slow
the current load rate seen by the bulk capacitors. The bulk filter
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FN8604.4
February 6, 2015
ISL70003SEH
capacitor values are generally determined by the ESR (Effective
Series Resistance) and voltage rating requirements rather than
actual capacitance requirements.
High-frequency decoupling capacitors should be placed as close
to the power pins of the load as physically possible. Be careful
not to add inductance in the circuit board wiring that could
cancel the usefulness of these low inductance components.
The shape of the output voltage waveform during a load transient
that represents the worst case loading conditions will ultimately
determine the number of output capacitors and their type. When
this load transient is applied to the converter, most of the energy
required by the load is initially delivered from the output
capacitors. This is due to the finite amount of time required for
the inductor current to slew up to the level of the output current
required by the load. This phenomenon results in a temporary dip
in the output voltage. At the very edge of the transient, the
Equivalent Series Inductance (ESL) of each capacitor induces a
spike that adds on top of the existing voltage drop due to the
Equivalent Series Resistance (ESR).
After the initial spike, attributable to the ESR and ESL of the
capacitors, the output voltage experiences sag. This sag is a
direct consequence of the amount of capacitance on the output.
In a typical converter design, the ESR of the output capacitor
bank dominates the transient response. The ESR and the ESL are
typically the major contributing factors in determining the output
capacitance. The number of output capacitors can be
determined by using Equation 16, which relates the ESR and ESL
of the capacitors to the transient load step and the voltage limit
(ΔVo).
ESL ² dI tran
------------------------------------------+ ESR ² Itran
dt
Number of Capacitors = --------------------------------------------------------------------------------------------V o
(EQ. 16)
If ΔVSAG and/or ΔVHUMP are found to be too large for the output
voltage limits, then the amount of capacitance may need to be
increased. In this situation, a trade-off between output inductance
and output capacitance may be necessary.
The ESL of the capacitors, which is an important parameter in
the previous equations, is not usually listed in databooks.
Practically, it can be approximated using Equation 17 if an
Impedance vs Frequency curve is given for a specific capacitor:
1
ESL = -----------------------------------------------------2
C  2 ²  ² f res 
(EQ. 17)
Where: fres is the frequency where the lowest impedance is
achieved (resonant frequency).
ΔVHUMP
VOUT
The ESL of the capacitors becomes a concern when designing
circuits that supply power to loads with high rates of change in
the current.
ΔVESR
ΔVSAG
Input Capacitor Selection
ΔVESL
IOUT
Use a mix of input bypass capacitors to control the voltage
overshoot across the MOSFETs. Use small ceramic capacitors for
high-frequency decoupling and bulk capacitors to supply the
current needed each time the upper MOSFET turns on. Place the
small ceramic capacitors physically close to the MOSFETs and
between the drain of the upper MOSFET and the source of the
lower MOSFET.
ITRAN
FIGURE 46. TYPICAL TRANSIENT RESPONSE
During the removal of the same output load, the energy stored in
the inductor is dumped into the output capacitors. This energy
dumping creates a temporary hump in the output voltage. This
hump, as with the sag, can be attributed to the total amount of
capacitance on the output. Figure 46 shows a typical response to
a load transient.
The amplitudes of the different types of voltage excursions can
be approximated using Equation 15.
The maximum RMS current through the input capacitors may be
closely approximated using Equation 18:
dI tran
V ESL = ESL ² --------------------dt
V ESR = ESR ² I tran
The important parameters for the bulk input capacitance are the
voltage rating and the RMS current rating. For reliable operation,
select bulk capacitors with voltage and current ratings above the
maximum input voltage and largest RMS current required by the
circuit. Their voltage rating should be at least 1.25x greater than
the maximum input voltage, while a voltage rating of 1.5x is a
conservative guideline. For most cases, the RMS current rating
requirement for the input capacitor of a buck regulator is
approximately 1/2 the DC load current.
2
L OUT ² I tran
V SAG = ---------------------------------------------------------------------------C OUT ²  V IN – V OUT 
2
V OUT
V OUT 
2 
1  V IN – V OUT V OUT 
---------------- x  I OUT
x 1 – ---------------- + --------- x  ---------------------------------- x ---------------- 

V IN  12  Lxf OSC
MAX
V IN 
V IN  
(EQ. 18)
2
L OUT ² I tran
V HUMP = ------------------------------------------------C OUT ² V OUT
(EQ. 15)
Where Itran = Output Load Current Transient and COUT = Total
Output Capacitance
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For surface mount designs, solid tantalum capacitors can be
used, but caution must be exercised with regard to the capacitor
surge current rating. These capacitors must be capable of
handling the surge current at power-up. Some capacitor series
available from reputable manufacturers are surge current tested.
FN8604.4
February 6, 2015
ISL70003SEH
Feedback Compensation
100
fZ1 fZ2
VIN
DRIVER
PWM
COMPARATOR
OPEN LOOP
ERROR AMP GAIN
40
20
20LOG
(R2/R1)
+
ΔVOSC
DRIVER
VOUT
PHASE
CO
ZIN
REFERENCE
ERROR
AMP
fLC
10
100
1k
fESR
10k
100k
FREQUENCY (Hz)
1M
10M
Equation 20 relates the compensation network’s poles, zeros
and gain to the components (R1 , R2 , R3 , C1 , C2 and C3) in
Figure 47. Use these guidelines for locating the poles and zeros
of the compensation network:
VEA
+
-60
COMPENSATION
GAIN
CLOSED LOOP
GAIN
MODULATOR
GAIN
FIGURE 48. ASYMPTOTIC BODE PLOT OF CONVERTER GAIN
ESR
(PARASITIC)
ZFB
20LOG
(VIN/DVOSC)
0
-40
LO
fP2
60
-20
OSC
fP1
80
GAIN (dB)
Figure 47 highlights the voltage-mode control loop for a
synchronous rectified buck converter. The output voltage (VOUT)
is regulated to the reference voltage level. The error amplifier
output (VEA) is compared with the oscillator (OSC) triangular
wave to provide a pulse-width modulated (PWM) wave with an
amplitude of VIN at the PHASE node. The PWM wave is smoothed
by the output filter (LO and CO).
1. Pick Gain (R2/R1) for desired converter bandwidth.
2. Place 1st Zero Below Filter’s Double Pole (~75% FLC).
DETAILED COMPENSATION COMPONENTS
ZFB
C1
C2
ZIN
C3
R2
3. Place 2nd Zero at Filter’s Double Pole.
VOUT
4. Place 1st Pole at the ESR Zero.
5. Place 2nd Pole at Half the Switching Frequency.
R3
6. Check Gain against Error Amplifier’s Open-Loop Gain.
R1
VERR
7. Estimate Phase Margin - Repeat if Necessary.
FB
+
Compensation Break Frequency Equations
R4
REFERENCE
R 

1
V OUT = 0.6 ¥  1 + -------
R 

4
FIGURE 47. VOLTAGE-MODE BUCK CONVERTER COMPENSATION
The modulator transfer function is the small-signal transfer
function of VOUT/VEA . This function is dominated by a DC Gain and
the output filter (LO and CO), with a double pole break frequency at
fLC and a zero at fESR . The DC gain of the modulator is simply the
input voltage (VIN) divided by the peak-to-peak oscillator voltage
ΔVOSC . The ISL70003SEH incorporates a feed-forward loop that
accounts for changes in the input voltage. This maintains a
constant modulator gain of 5, typical.
Modulator Break Frequency Equations
1
f LC = -----------------------------------------------------2  x LO x CO
1
f ESR = -----------------------------------------------------2  x ESR x C
O
(EQ. 19)
The compensation network consists of the error amplifier and
the impedance networks ZIN and ZFB. The goal of the
compensation network is to provide a closed loop transfer
function with the highest 0dB crossing frequency (f0dB) and
adequate phase margin. Phase margin is the difference between
the closed loop phase at f0dB and 180°.
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25
1
f Z1 = ----------------------------------------------2 x R 2 x C 1
1
f P1 = ------------------------------------------------------------------------ C 1 x C 2
2 x R 2 x  ---------------------------
 C 1 + C 2
1
f Z2 = ------------------------------------------------------------------------2 x  R 1 + R 3  x C 3
1
f P2 = ----------------------------------------------2 x R 3 x C 3
(EQ. 20)
Figure 48 shows an asymptotic plot of the DC/DC converter’s
gain vs frequency. The actual Modulator Gain has a high gain
peak due to the high Q factor of the output filter and is not shown
in Figure 48. Using the guidelines provided should give a
Compensation Gain similar to the curve plotted. The open loop
error amplifier gain bounds the compensation gain. Check the
compensation gain at fP2 with the capabilities of the error
amplifier. The Closed Loop Gain is constructed on the graph of
Figure 48 by adding the Modulator Gain (in dB) to the
Compensation Gain (in dB). This is equivalent to multiplying the
modulator transfer function to the compensation transfer
function and plotting the gain. The compensation gain uses
external impedance networks ZFB and ZIN to provide a stable,
high bandwidth (BW) overall loop. A stable control loop has a
gain crossing with -20dB/decade slope and a phase margin
greater than +45°. Include worst case component variations
when determining phase margin. A more detailed explanation of
voltage mode control of a buck regulator can be found in Tech
Brief TB417, entitled “Designing Stable Compensation Networks
for Single Phase Voltage Mode Buck Regulators”.
FN8604.4
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ISL70003SEH
PCB Design
LX Connection
PCB design is critical to high-frequency switching regulator
performance. Careful component placement and trace routing
are necessary to reduce voltage spikes and minimize
undesirable voltage drops. Selection of a suitable thermal
interface material is also required for optimum heat dissipation
and to provide lead strain relief.
Use a small island of copper to connect the LXx pins of the IC to
the output inductor on layers 1 and 4. Void the copper on layers 2
and 3 adjacent to the island to minimize capacitive coupling to
the power and ground planes. Place most of the island on layer 4
to minimize the amount of copper that must be voided from the
ground plane (layer 2).
Keep all other signal traces as short as possible.
PCB Plane Allocation
A minimum of four layers of two ounce copper are
recommended. Layer 2 should be a dedicated ground plane with
all critical component ground connections made with vias to this
layer. Layer 3 should be a dedicated power plane split between
the input and output power rails. Layers 1 and 4 should be used
primarily for signals, but can also provide additional power and
ground islands as required.
Thermal Management for Ceramic Package
For optimum thermal performance, place a pattern of vias on the
top layer of the PCB directly underneath the IC. Connect the vias
to the plane which serves as a heatsink. To ensure good thermal
contact, thermal interface material such as a Sil-Pad or thermally
conductive epoxy should be used to fill the gap between the vias
and the bottom of the IC of the ceramic package.
PCB Component Placement
Lead Strain Relief
Components should be placed as close as possible to the IC to
minimize stray inductance and resistance. Prioritize the
placement of bypass capacitors on the pins of the IC in the order
shown: REF, SS, AVDD, DVDD, PVINx (high-frequency capacitors),
EN, PGOOD, PVINx (bulk capacitors).
The package leads protrude from the bottom of the package and
the leads need forming to provide strain relief. On the ceramic
bottom package R64.A, the Sil-pad or epoxy maybe be used to fill
the gap left between the PCB board and the bottom of the
package when lead forming is completed. On the heatsink option
of the package R64.C, the lead forming should be made so that
the bottom of the heatsink and the formed leads are flush.
Locate the output voltage resistive divider as close as possible to
the FB pin of the IC. The top leg of the divider should connect
directly to the output of the inductor via a kelvin trace and the
bottom leg of the divider should connect directly to AGND. This
AGND connection should also be a kelvin trace connected to the
closest ground to the inductor output. The junction of the
resistive divider should connect directly to the FB pin.
If desired place a Schottky clamp diode as close as possible to
the LXx and PGNDx pins of the IC. A small series R-C snubber
connected from the LXx pins to the PGNDx pins may be used to
damp high-frequency ringing on the LXx pins if desired.
Heatsink Mounting Guidelines
The R64.C package option has a heatsink mounted on the
underside of the package. The following JESD-51x series
guidelines may be used to mount the package:
1. Place a thermal land on the PCB under the heatsink.
2. The land should be approximately the same size as to 1mm
larger than the 10.16x10.16mm heatsink.
3. Place an array of thermal vias below the thermal land.
- Via array size: ~9x9 = 81 thermal vias.
LOUT
LXx
RS
3A
VOUT
COUT
CS
ERROR
AMPLIFIER
+
RT
PGNDx
- Via diameter: ~0.3mm drill diameter with plated copper on
the inside of each via.
- Via pitch: ~1.2mm.
- Vias should drop to and contact as much metal area as
feasible to provide the best thermal path.
Heatsink Electrical Potential
FB
RB
NI
REF
CREF
FIGURE 49. SCHOTTKY DIODE AND R-C SNUBBER
The heatsink is connected to pin 50 within the package; thus the
PCB design and potential applied to pin 50 will therefore define
the heatsink potential.
Heatsink Mounting Materials
In the case of electrically conductive mounting methods
(conductive epoxy, solder, etc) the thermal land, vias and
connected plane(s) below must be the same potential as pin 50.
In the case of electrically non-conductive mounting methods
(non-conductive epoxy), the heatsink and pin 50 could have
different electrical potential than the thermal land, vias and
connected plane(s) below.
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26
FN8604.4
February 6, 2015
ISL70003SEH
Package Characteristics
TOP METALLIZATION
Type: AlCu (99.5%/0.5%)
Thickness: 2.7µm ±0.4µm
Weight of Packaged Device
1.43 Grams (typical) - R64.A Package
2.65 Grams (typical) - R64.C Package
BACKSIDE FINISH
Silicon
Lid Characteristics
PROCESS
Finish: Gold
Lid Potential: PGND
0.6µM BiCMOS Junction Isolated
ASSEMBLY RELATED INFORMATION
Die Characteristics
Substrate and Lid Potential
Die Dimensions
PGND
8300µm x 8300µm (327 mils x 327 mils)
Thickness: 300µm ± 25.4µm (12 mils ± 1 mil)
ADDITIONAL INFORMATION
Worst Case Current Density
Interface Materials
<2 x 105 A/cm2
GLASSIVATION
Transistor Count
Type: Silicon Oxide and Silicon Nitride
Thickness: 0.3µm ± 0.03µm to 1.2µm ± 0.12µm
26,144
Metallization Mask Layout
LX8
PVIN8
PGND8
LX7
PGND7
PVIN7
PVIN6
LX6
PGND6
LX5
PGND5
PVIN5
PVIN4
LX4
PGND4
LX3
PGND3
PVIN3
ISL70003SEH
DE
PVIN2
PVIN9
LX2
LX9
PGND2
PGND9
PGND1
PGND10
LX1
LX10
PVIN1
PVIN10
IMON
SEL2
SEL1
SGND
OCSETA
PGOOD
OCSETB
GND
GND
GND
GND
GND
BUFIN+
BUFINBUFOUT
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27
SYNC
SS
F300
RTCT
ENABLE
VREFD
VDDD
VREF_OUTS
GNDD
GNDA
VDDA
VREFA
POR_VIN
VERR
FB
ORIGIN
NI
VREF
FN8604.4
February 6, 2015
ISL70003SEH
TABLE 2. LAYOUT X-Y COORDINATES
PAD NUMBER
X
(µm)
Y
(µm)
dX
(µm)
dY
(µm)
BOND WIRES
SIZE (0.001”)
NI
1
0
0
135
135
1.5
FB
2
452
0
135
135
1.5
Verr
3
929
0
135
135
1.5
POR_VIN
4
1371
0
135
135
1.5
VrefA
5
1854
58
254
254
3
VDDA
6
2577
60
254
254
3
GNDA
7
3104
60
254
254
3
GNDD
8
3589
60
254
254
3
Vref OUTs
9
4035
60
254
254
3
VDDD
10
4713
60
254
254
3
VrefD
11
5420
60
254
254
3
ENABLE
12
5846
0
135
135
1.5
RtCt
13
6274
0
135
135
1.5
F300
14
6579
0
135
135
1.5
Sync
15
6976
0
135
135
1.5
SS Cap
16
7201
51
135
135
1.5
TDI
17
7201
345
135
135
1.5
Zap
18
7201
639
135
135
1.5
TDO
19
7201
934
135
135
1.5
TST Trim
20
7201
1228
135
135
1.5
TCLK
21
7201
1522
135
135
1.5
Pgood
22
7201
1902
135
135
1.5
SEL1
23
7201
2275
135
135
1.5
SEL2
24
7201
2569
135
135
1.5
PVin10
25
7140
3285
254
254
3
LX10
26
6350
3771
254
254
3
PGND10
27
5387
4179
254
254
3
PGND9
28
5387
4625
254
254
3
LX9
29
6350
5033
254
254
3
PVin9
30
7140
5518
254
254
3
Deon
31
7220
6303
135
135
1.5
PVin8
32
7140
7578
254
254
3
LX8
33
6655
6788
254
254
3
PGND8
34
6247
5825
254
254
3
PGND7
35
5801
5825
254
254
3
LX7
36
5393
6788
254
254
3
PVin7
37
4908
7578
254
254
3
PVin6
38
4497
7578
254
254
3
LX6
39
4011
6788
254
254
3
PAD NAME
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28
FN8604.4
February 6, 2015
ISL70003SEH
TABLE 2. LAYOUT X-Y COORDINATES (Continued)
PAD NUMBER
X
(µm)
Y
(µm)
dX
(µm)
dY
(µm)
BOND WIRES
SIZE (0.001”)
PGND6
40
3603
5825
254
254
3
PGND5
41
3157
5825
254
254
3
LX5
42
2749
6788
254
254
3
PVin5
43
2264
7578
254
254
3
PVin4
44
1853
7578
254
254
3
LX4
45
1367
6788
254
254
3
PGND4
46
960
5825
254
254
3
PGND3
47
514
5825
254
254
3
LX3
48
106
6788
254
254
3
PVin3
49
-379
7578
254
254
3
PVIN2
50
-379
5518
254
254
3
LX2
51
411
5033
254
254
3
PGND2
52
1374
4625
254
254
3
PGND1
53
1374
4179
254
254
3
LX1
54
411
3771
254
254
3
PVin1
55
-379
3285
254
254
3
Imon
56
-438
2561
135
135
1.5
sgnd
57
-438
2201
135
135
1.5
OCSETA
58
-438
1841
135
135
1.5
OCSETB
59
-438
1481
135
135
1.5
Buf IN +
60
-438
1121
135
135
1.5
Buf IN -
61
-438
761
135
135
1.5
Buf OUT
62
-438
401
135
135
1.5
Vref
63
-438
41
135
135
1.5
PAD NAME
For additional products, see www.intersil.com/en/products.html
Intersil products are manufactured, assembled and tested utilizing ISO9001 quality systems as noted
in the quality certifications found at www.intersil.com/en/support/qualandreliability.html
Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time
without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be
accurate and reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third
parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.
For information regarding Intersil Corporation and its products, see www.intersil.com
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29
FN8604.4
February 6, 2015
ISL70003SEH
Revision History
The revision history provided is for informational purposes only and is believed to be accurate, but not warranted. Please go to the web to make sure that
you have the latest revision.
DATE
REVISION
CHANGE
February 6, 2015
FN8604.4
On page 6, added text in the FB, PVINx, SEL1, SEL2 and IMON pin descriptions.
On page 7 corrected pin names in Figure 3.
On page 8 corrected pin names in Figure 4.
On page 9, updated Note 5 by adding "with any negative inductor current".
On page 23, added the fifth paragraph under the DDR Configuration section.
On page 26, added text to the second paragraph under “PCB Component Placement”.
March 7, 2014
FN8604.3
Added new feedback link, updated Related Literature and updated About Intersil.
March 3, 2014
FN8604.2
Cosmetic edits throughout file.
December 20, 2013
FN8604.1
Initial Release.
About Intersil
Intersil Corporation is a leading provider of innovative power management and precision analog solutions. The company's products
address some of the largest markets within the industrial and infrastructure, mobile computing and high-end consumer markets.
For the most updated datasheet, application notes, related documentation and related parts, please see the respective product
information page found at www.intersil.com.
You may report errors or suggestions for improving this datasheet by visiting www.intersil.com/ask.
Reliability reports are also available from our website at www.intersil.com/support
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30
FN8604.4
February 6, 2015
ISL70003SEH
Package Outline Drawing
R64.A
64 CERAMIC QUAD FLATPACK PACKAGE (CQFP)
Rev 5, 10/13
1.118 (28.40)
1.080 (27.43)
0.567 (14.40)
0.547 (13.90)
0.290 (7.37)
0.255 (6.48)
64
0.025 (0.635) BSC
49
1
PIN 1
INDEX AREA
48
0.567 (14.40)
0.547 (13.90)
1.118 (28.40)
1.080 (27.43)
0.010 (0.25)
0.006 (0.15)
33
16
17
32
SEE DETAIL "A"
TOP VIEW
0.105 (2.67)
0.075 (1.91)
0.0075 (0.188)
0.005 (0.125)
SIDE VIEW
0.380 (9.655)
0.370 (9.395)
0.008 (0.20)
REF
DETAIL “A”
0.100 (2.537)
0.085 (2.157)
PIN 1
INDEX AREA
1
64
NOTE:
1. All dimensions are in inches (millimeters).
BOTTOM VIEW
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31
FN8604.4
February 6, 2015
ISL70003SEH
Package Outline Drawing
R64.C
64 CERAMIC QUAD FLATPACK PACKAGE (CQFP) WITH BOTTOM HEATSINK
Rev 1, 10/13
1.118 (28.40)
1.080 (27.43)
0.567 (14.40)
0.547 (13.90)
0.290 (7.37)
0.255 (6.48)
64
0.025 (0.635) BSC
1
49
PIN 1
INDEX AREA
48
0.567 (14.40)
0.547 (13.90)
1.118 (28.40)
1.080 (27.43)
0.010 (0.25)
0.006 (0.15)
33
16
17
32
SEE DETAIL "A"
TOP VIEW
0.0075 (0.188)
0.005 (0.125)
0.135 (3.43)
0.111 (2.82)
SIDE VIEW
HEATSINK
0.405 (10.29)
0.395 (10.03)
0.380 (9.655)
0.370 (9.395)
0.100 (2.537)
0.085 (2.157)
0.008 (0.20)
REF
0.048 (1.22)
REF
0.026 (0.66) MIN. 2
HEATSINK
DETAIL "A"
PIN 1
INDEX AREA
0.405 (10.29)
0.395 (10.03)
1
64
NOTES:
1. All dimensions are in inches (millimeters)
BOTTOM VIEW
Submit Document Feedback
32
2. Dimension shall be measured at point of exit
(beyond the meniscus) of the lead from the body.
FN8604.4
February 6, 2015