Linear ANALOG DEVICES LTM4680 User manual

LTM4680
1
Rev. B
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TYPICAL APPLICATION
FEATURES DESCRIPTION
Dual 30A or Single 60A µModule Regulator
with Digital Power System Management
The LTM
®
4680 is a dual 30A or single 60A step-down
µModule
®
(power module) DC/DC regulator featuring
remote configurability and telemetry-monitoring of power
management parameters over PMBus—an open stan-
dard I2C-based digital interface protocol. The LTM4680
is comprised of digitally programmable analog control
loops, precision mixed-signal circuitry, EEPROM, power
MOSFETs, inductors and supporting components.
The LTM4680 product video is available on the website.
The LTM4680’s 2-wire serial interface allows outputs
to be margined, tuned and ramped up and down at pro-
grammable slew rates with sequencing delay times. True
input current sense, output currents and voltages, output
power, temperatures, uptime and peak values are read-
able. Custom configuration of the EEPROM contents is not
required. At start-up, output voltages, switching frequency,
and channel phase angle assignments can be set by pin-
strapping resistors. The LTpowerPlay
®
GUI and DC1613
USB-to-PMBus converter and demo kits are available.
The LTM4680 is offered in a 16mm ×16mm ×7.82mm
BGA package available with SnPb or RoHS compliant ter-
minalfinish. Pin compatible with LTM4678.
APPLICATIONS
n Dual 30A or Single 60A Digitally Adjustable Analog
Loops with Digital Interface for Control and Monitoring
n Wide Input Voltage Range: 4.5V to 16V
n Output Voltage Range: 0.5V to 3.3V
n 90% Full Load Efficiency from 12VIN to 1VOUT at 60A
n ±0.5% Maximum DC Output Error Over Temperature
n ±2.5% Current Readback Accuracy (25°C to 125°C)
n Integrated Input Current Sense Amplifier
n 400kHz PMBus-Compliant I2C Serial Interface
n Supports Telemetry Polling Rates up to 125Hz
n Constant Frequency Current Mode Control
n Parallel and Current Share Multiple Modules
n Pin Compatible with LTM4678
n 16mm ×16mm ×7.82mm BGA Package
Readable Data:
n Input and Output Voltages, Currents, and Temperatures
n Running Peak Values, Uptime, Faults and Warnings
n Onboard EEPROM Fault Log Record
Writable Data and Configurable Parameters:
n Output Voltage, Voltage Sequencing and Margining
n Digital Soft-Start/Stop Ramp, Program Analog Loop
n OV/UV/OT, UVLO, Frequency and Phasing
n System Optimization, Characterization and Data Mining
in Prototype, Production and Field Environments
All registered trademarks and trademarks are the property of their respective owners. Protected
by U.S. Patents including 5408150, 5481178, 5705919, 5929620, 6144194, 6177787, 6580258,
7420359, 8163643. Licensed under U.S. Patent 7000125 and other related patents worldwide.
Dual 30A µModule Regulator with Digital Interface for Control and Monitoring* Efficiency vs Current at 12V Input
1.0V, 250kHz
1.5V, 425kHz
LOAD CURRENT (A)
0
5
10
15
20
25
30
65
70
75
80
85
90
95
100
EFFICIENCY (%)
4680 TA01b
RSENSE
22µF
×5
100µF
×8
100µF
×8
VOSNS0+
VOSNS0–
FAULT0
FAULT1
WP
SYNC
VIN0
VOUT0
SCL
SDA
RUN0
RUN1
VIN1
VOSNS1+
VOUT1
ALERT
SHARE_
CLK
GND
SVIN
VOSNS1–
SGND
IN+
IN–
LTM4680
LOAD0
LOAD1
I2C/SMBus I/F WITH PMBus
COMMAND SET TO/FROM
IPMI OR OTHER BOARD
MANAGEMENT CONTROLLER
4.5V to 16V
(FROM
4.5V TO 5.75V,
CONNECT
VIN, SVIN
AND INTVCC
TOGETHER)
ON/OFF CONTROL
FAULT INTERRUPTS
SYNCHRONIZATION TIME-BASE
REGISTER WRITE PROTECTION
VOUT1
ADJUSTABLE
UP TO 30A
VOUT0
ADJUSTABLE
UP TO 30A
4680 TA01a
*FOR COMPLETE CIRCUIT, SEE FIGURE 46
Click to view associated Video Design Idea.

LTM4680
2
Rev. B
For more information www.analog.com
TABLE OF CONTENTS
Features..................................................... 1
Applications ................................................ 1
Typical Application ........................................ 1
Description.................................................. 1
Table of Contents .......................................... 2
Absolute Maximum Ratings.............................. 4
Order Information.......................................... 4
Pin Configuration .......................................... 4
Electrical Characteristics ................................. 5
Typical Performance Characteristics .................. 12
Pin Functions .............................................. 15
Simplified Block Diagram ............................... 19
Decoupling Requirements............................... 19
Functional Diagram ...................................... 20
Test Circuits ............................................... 21
Operation................................................... 23
Power Module Introduction ...................................23
Power Module Overview, Major Features................23
EEPROM with ECC ................................................. 24
Power-Up and Initialization ....................................25
Soft-Start ...............................................................26
Time-Based Sequencing ........................................26
Voltage-Based Sequencing ....................................26
Shutdown ..............................................................27
Light-Load Current Operation ................................27
Switching Frequency and Phase .............................28
PWM Loop Compensation .....................................28
Output Voltage Sensing .........................................28
INTVCC/EXTVCC Power ..........................................28
Output Current Sensing and Sub Milliohm
DCRCurrent Sensing .............................................29
Input Current Sensing ............................................29
PolyPhase Load Sharing ........................................29
External/Internal Temperature Sense .....................30
RCONFIG (Resistor Configuration) Pins .................30
Table1. VOUTn_CFG Pin Strapping Look-Up Table for
the LTM4680’s Output Voltage, Coarse Setting (Not
Applicable if MFR_CONFIG_ALL[6] = 1b).............31
Table2. VTRIMn_CFG Pin Strapping Look-Up
Table for the LTM4680’s Output Voltage, Fine
Adjustment Setting (Not Applicable if MFR_
CONFIG_ALL[6] = 1b) ........................................31
Table3. FSWPH_CFG Pin Strapping Look-Up Table
to Set the LTM4680’s Switching Frequency and
Channel Phase-Interleaving Angle (Not Applicable
if MFR_CONFIG_ALL[6] = 1b) ...........................32
Table4. ASEL Pin Strapping Look-Up Table to
Set the LTM4680’s Slave Address (Applicable
Regardless of MFR_CONFIG_ALL[6] Setting) ....33
Table5. LTM4680 MFR_ADDRESS Command
Examples Expressed in 7- and 8-Bit Addressing .... 33
Fault Detection and Handling .................................33
Status Registers and ALERT Masking ..................34
Figure5. LTM4680 Status Register Summary......35
Mapping Faults to FAULT Pins .............................36
Power Good Pins .................................................36
CRC Protection ....................................................36
Serial Interface ......................................................36
Communication Protection ..................................36
Device Addressing .................................................36
Responses to VOUT and IIN/IOUT Faults ..................37
Output Overvoltage Fault Response ....................37
Output Undervoltage Response ...........................38
Peak Output Overcurrent Fault Response ............38
Responses to Timing Faults ...................................38
Responses to VIN OV Faults ...................................38
Responses to OT/UT Faults ....................................38
Internal Overtemperature Fault Response ............38
External Overtemperature and
UndertemperatureFaultResponse ....................39
Responses to Input Overcurrent and Output
Undercurrent Faults ...............................................39
Responses to External Faults .................................39
Fault Logging .........................................................39
Bus Timeout Protection .........................................39
Similarity Between PMBus, SMBus and I2C
2-WireInterface .....................................................40
PMBus Serial Digital Interface ...............................40
Table6. Abbreviations of Supported Data Formats ...41
Figure6. PMBus Timing Diagram ......................... 41
Figures 7 to 24 PMBus Protocols ...........................42

LTM4680
3
Rev. B
For more information www.analog.com
TABLE OF CONTENTS
PMBus Command Summary ............................ 45
PMBus Commands ................................................45
Table7. PMBus Commands Summary (Note:
The Data Format Abbreviations Are Detailed in
Table8) ...........................................................45
Table8. Data Format Abbreviations .....................50
Applications Information ................................ 51
VIN to VOUT Step-Down Ratios ............................... 51
Input Capacitors .................................................... 51
Output Capacitors .................................................. 51
Light Load Current Operation ................................. 51
Switching Frequency and Phase ............................52
Output Current Limit Programming .......................53
Minimum On-Time Considerations .........................54
Variable Delay Time, Soft-Start and Output
VoltageRamping ...................................................54
Digital Servo Mode ................................................54
Soft Off (Sequenced Off) .......................................55
Undervoltage Lockout ............................................56
Fault Detection and Handling .................................56
Open-Drain Pins ....................................................56
Phase-Locked Loop and Frequency Synchronization . 57
Input Current Sense Amplifier ................................58
Programmable Loop Compensation ......................58
Checking Transient Response ................................59
PolyPhase Configuration .....................................60
Connecting The USB to I2C/SMBus/PMBus
Controllerto the LTM4680 In System ....................60
LTpowerPlay:An Interactive GUI for Digital Power....... 61
PMBus Communication and Command
Processing .............................................................61
Thermal Considerations and Output
CurrentDerating ..................................................63
Tables 10 thru 11: Output Current Derating...........66
Table12. Channel Output Voltage vs Capacitor
Selection, All Ceramic Configuration, 15A to 30A
Load Step with 15A/µs Slew Rate ......................66
Table13. Channel Output Voltage vs Capacitor
Selection, Bulk and Ceramic Cap Configuration,
15A to 30A Load Step with 15A/µs Slew Rate ...67
Table14. Dual Phase Single Output Voltage vs
Capacitor Selection, Bulk and Ceramic Cap
Configuration, 30A to 60A Load Step with 30A/µs
Slew Rate ..........................................................68
Derating Curves ......................................................69
EMI Performance ...................................................70
Safety Considerations ............................................70
Layout Checklist/Example .....................................70
Typical Applications ...................................... 72
PMBus Command Details ............................... 77
Addressing and Write Protect.................................77
General Configuration Commands..........................79
On/Off/Margin ........................................................80
PWM Configuration ................................................82
Voltage....................................................................85
Input Voltage and Limits.......................................85
Output Voltage and Limits ....................................86
Output Current and Limits ......................................89
Input Current and Limits ......................................91
Temperature............................................................92
Power Stage DCR Temperature Calibration...........92
Timing ....................................................................93
Timing—On Sequence/Ramp...............................93
Timing—Off Sequence/Ramp ..............................94
Precondition for Restart .......................................95
Fault Response .......................................................95
Fault Responses All Faults....................................95
Fault Responses Input Voltage .............................96
Fault Responses Output Voltage...........................96
Fault Responses Output Current...........................99
Fault Responses IC Temperature ........................ 100
Fault Responses External Temperature............... 101
Fault Sharing......................................................... 102
Fault Sharing Propagation .................................. 102
Fault Sharing Response...................................... 104
Scratchpad ........................................................... 104
Identification......................................................... 105
Fault Warning and Status...................................... 106
Telemetry.............................................................. 113
NVM Memory Commands .................................... 117
Store/Restore ..................................................... 117
Fault Logging...................................................... 118
Block Memory Write/Read.................................. 122
Package Description ................................... 123
Table23. LTM4680 BGA Pinout.......................... 123
Revision History ........................................ 125
Package Photograph ................................... 126
Design Resources ...................................... 126
Related Parts ............................................ 126

LTM4680
4
Rev. B
For more information www.analog.com
PIN CONFIGURATIONABSOLUTE MAXIMUM RATINGS
Terminal Voltages:
VINn(Note 4), SVIN, IIN+, IIN−...................... –0.3V to 18V
(SVIN – IIN+), (IIN+– IIN−)........................... –0.3V to 0.3V
SW0, SW1 .................. −1V to 18V, −5V to 18V Transient
INTVCC, EXTVCC........................................... –0.3V to 6V
VOUTn........................................................ –0.3V to 3.6V
VOSNS0+, VOSNS1+......................................... –0.3V to 6V
VOSNS0−, VOSNS1−...................................... –0.3V to 0.3V
RUNn, SDA, SCL, ALERT ........................... –0.3V to 5.5V
FSWPH_CFG, VOUT0,1_CFG,
VTRIM0,1_CFG, ASEL ......................... –0.3V to 2.75V
FAULTn, SYNC, SHARE_CLK, WP,
PGOOD0, PGOOD1 ............................... −0.3V to 3.6V
COMPna, COMPnb, .................................. –0.3V to 2.7V
TSNS0a, TSNS1a...................................... –0.3V to 2.2V
TSNS0b, TSNS1b...................................... –0.3V to 0.8V
Temperatures
Internal Operating Temperature Range
(Notes 2, 13, 16, 17) .............................. –40°C to 125°C
Storage Temperature Range .................. –55°C to 125°C
Peak Solder Reflow Package Body Temperature... 245°C
(Not recommended for upside down reflow.)
(Note 1)
1 2 3 4 5 6 7 8 9 10 11 12
M
L
K
J
H
G
F
E
D
C
B
A
GND
GND
GND
VOUT0
GND
INTVCC VDD33
FSWPH_
CFG
VOUT0_
CFG
SHARE
CLK
VOUT1_
CFG
VTRIM1_
CFG
EXTVCC
GND
RUN1
PGOOD1
PGOOD0
VOSNS0+VOSNS0–
TOP VIEW
BGA PACKAGE
144-LEAD (16mm × 16mm × 7.82mm)
TJMAX = 125°C, θJCtop = 3.3°C/W, θJCbottom = 2°C/W, θJB = 2°C/W, θJA = 7°C/W
WEIGHT = 7.4 GRAMS
GND VOUT0
VOSNS1+VOSNS1–
VOUT1
VOUT1
SGND
VIN0
VIN1
SW0
SW1
SVIN
IIN+
IIN–
VDD25
ASEL
VTRIM0_
CFG
RUN0
FAULT0ALERT
FAULT1
COMP0b SDA
COMP0a
COMP1b
COMP1a
SYNC
SCLTSNS0aTSNS1aTSNS0b
TSNS1b
WP
ORDER INFORMATION
PART NUMBER PAD OR BALL FINISH
PART MARKING* PACKAGE
TYPE
MSL
RATING
TEMPERATURE RANGE
(See Note 2)
DEVICE FINISH CODE
LTM4680EY#PBF SAC305 (RoHS) LTM4680Y e1 BGA 4 –40°C to 125°CLTM4680IY#PBF LTM4680Y
LTM4680IY SnPb (63/37) LTM4680Y e0
Contact the factory for parts specified with wider operating temperature
ranges. *Device temperature grade is indicated by a label on the shipping
container. Pad or ball finish code is per IPC/JEDEC J-STD-609.
• Recommended LGA and BGA PCB Assembly and Manufacturing
Procedures
• LGA and BGA Package and Tray Drawings

LTM4680
5
Rev. B
For more information www.analog.com
ELECTRICAL CHARACTERISTICS
The ldenotes the specifications which apply over the specified internal
operating temperature range (Note 2). nis specified as each individual output channel (Note 4). TA= 25°C, VIN = 12V, RUNn = 3.3V,
EXTVCC=0, FREQUENCY_SWITCH = 350kHz and VOUTncommanded to 1.000V unless otherwise noted. Configured with factory-default
EEPROM settings and per Test Circuit 1, unless otherwise noted.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VIN Input DC Voltage Test Circuit 1
Test Circuit 2; VIN_OFF < VIN_ON = 4V
l
l
5.75
4.5
16
5.75
V
V
VOUTnRange of Output Voltage Regulation VOUTnDifferentially Sensed on VOSNSn+/VOSNSn– Pin-Pair;
Commanded by Serial Bus or with Resistors Present at
Start-Up on VOUTn_CFG
l0.5 3.34 V
VOUTn(DC) Output Voltage, Total Variation with
Line and Load
Digital Servo Engaged (MFR_PWM_MODEn[6] = 1b)
Digital Servo Disengaged (MFR_PWM_MODEn[6] = 0b)
VOUTnCommanded to 1.000V, VOUTnLow Range
(MFR_PWM_MODEn[1] = 1b) (Note 5)
l 0.995
0.985
1.000
1.000
1.005
1.015
V
V
VUVLO Undervoltage Lockout Threshold,
When VIN < 4.3V
VINTVCC Falling
VINTVCC Rising
3.55
3.90
V
V
Input Specifications
IINRUSH(VIN) Input Inrush Current at
Start-Up
Test Circuit 1, VOUTn=1V, VIN = 12V; No Load Besides
Capacitors; TON_RISEn= 3ms (Note 12)
50 mA
IQ(SVIN) Input Supply Bias Current Forced Continuous Mode, MFR_PWM_MODEn[0] = 1b
RUNn= 3.3V
Shutdown, RUN0 = RUN1 = 0V
37
25
mA
mA
IS(VINn,DCM) Input Supply Current in
Discontinuous Mode Operation
Discontinuous Mode, MFR_PWM_MODEn[0] = 0b,
IOUTn= 100mA
20 mA
IS(VINn,FCM) Input Supply Current in Forced-
Continuous Mode Operation
Forced Continuous Mode, MFR_PWM_MODEn[0] = 1b
VINn= 12V, VOUTn= 1V
IOUTn= 30A 3.2 A
Output Specifications
IOUTnOutput Continuous Current Range Utilizing MFR_PWM_MODE[7] = 1 for IOUT_OC_FAULT_
LIMIT, Page 90 (Note 6)
0 30 A
∆VOUTn(LINE)
VOUTn
Line Regulation Accuracy Digital Servo Engaged (MFR_PWM_MODEn[6] = 1b)
Digital Servo Disengaged (MFR_PWM_MODEn[6] = 0b)
SVIN and VINnElectrically Shorted Together and INTVCC
Open Circuit;IOUTn= 0A, 5.75V ≤ VIN ≤ 16V, VOUT Low Range
(MFR_PWM_MODEn[1] = 1b), FREQUENCY_SWITCH =
350kHz (Note 5)
l
0.03
0.03 ±0.2
%/V
%/V
∆VOUTn(LOAD)
VOUTn
Load Regulation Accuracy Digital Servo Engaged (MFR_PWM_MODEn[6] = 1b)
Digital Servo Disengaged (MFR_PWM_MODEn[6] = 0b)
0A ≤ IOUTn≤ 30A, VOUTnLow Range, (MFR_PWM_
MODEn[1] = 1b) (Note 5)
l
0.03
0.2 0.5
%
%
VOUTn(AC) Output Voltage Ripple 10 mVP-P
fS(Each Channel) VOUTnRipple Frequency FREQUENCY_SWITCH Set to 350kHz (0xFABC) l320 350 370 kHz
∆VOUTn(START) Turn-On Overshoot TON_RISEn= 3ms (Note 12) 8 mV
tSTART Turn-On Start-Up Time Time from VIN Toggling from 0V to 12V to Rising Edge
PGOODn. TON_DELAYn= 0ms, TON_RISEn= 3ms
l30 ms
tDELAY(0ms) Turn-On Delay Time Time from First Rising Edge of RUNnto Rising Edge of
PGOODn. TON_DELAYn= 0ms, TON_RISEn= 3ms,
VIN Having Been Established for at Least 70ms
l2.75 3.1 3.8 ms
∆VOUTn(LS) Peak Output Voltage Deviation for
Dynamic Load Step
Load: 0A to 15A and 15A to 0A at 15A/µs,
VOUTn= 1V, VIN = 12V (Note 12) See Transient Graph
60 mV
tSETTLE Settling Time for Dynamic Load Step Load: 0A to 15A and 15A to 0A at 15A/µs,
VOUTn= 1V, VIN = 12V (Note 12) See Transient Graphs
50 µs

LTM4680
6
Rev. B
For more information www.analog.com
ELECTRICAL CHARACTERISTICS
The ldenotes the specifications which apply over the specified internal
operating temperature range (Note 2). nis specified as each individual output channel (Note 4). TA= 25°C, VIN = 12V, RUNn= 3.3V,
EXTVCC=0, FREQUENCY_SWITCH = 350kHz and VOUTncommanded to 1.000V unless otherwise noted. Configured with factory-default
EEPROM settings and per Test Circuit 1, unless otherwise noted.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
IOUTn(OCL_AVG) Output Current Limit, Time
Averaged, Readback
Time-Averaged Output Inductor Current Limit Inception
Threshold, Commanded by IOUT_OC_FAULT_LIMITn
(Note12)
Utilizing MFR_PWM_MODE[7] = 0, Using IL PEAK = 40A,
Page 90
39 A
Control Section
VFBCMnFeedback Input Common Mode
Range
VOSNSn–Valid Input Range (Referred to SGND)
VOSNSn+Valid Input Range (Referred to SGND)
l
l
–0.1 0.3
3.6
V
V
VOUT-RNGL Full-Scale Command Voltage, Range
Low (0.5V to 2.75V)
Set Point Accuracy
Resolution
LSB Step Size
VOUTnCommanded to 2.750V, MFR_PWM_MODEn[1] = 1b
(Notes7,15)
−0.5
2.75
12
0.688
0.5
V
%
Bits
mV
VOUT-RNGH Full-Scale Command Voltage, Range
High (0.5V to 3.6V)
Set Point Accuracy
Resolution
LSB Step Size
VOUTnCommanded to 3.6V, MFR_PWM_MODEn[1] = 0b
Limit Design to 3.6V Operating for Module
(Notes7,15) –0.5
3.6
12
1.375
0.5
V
%
Bits
mV
RVSNS0+VOSNS0+Impedance to SGND 0.05V ≤ VVOSNS0+– VSGND ≤ 3.3V 50 kΩ
RVSNS1+VOSNS1+ Impedance to SGND 0.05V ≤ VVOSNS1+– VSGND ≤ 3.3V 50 kΩ
tON(MIN) Minimum On-Time (Note 8 ) 60 ns
RCOMP0,1 Resolution
Compensation Resistor RTH(MAX)
Compensation Resistor RTH(MIN)
MFR_PWM_CONFIG[4:0] = 0 to 31 (See Figure1) 5
62
0.5
Bits
kΩ
kΩ
gm0,1 Resolution
Error Amplifier gm(MAX)
Error Amplifier gm(MIN)
LSB Step Size
COMP0,1 = 1.35V, MFR_PWM_CONFIG[7:5] = 0 to 7 3
5.76
1
0.68
Bits
mmho
mmho
mmho
Analog OV/UV (Overvoltage/Undervoltage) Output Voltage Supervisor Comparators (VOUT_OV/UV_FAULT_LIMIT and VOUT_OV/UV_WARN_LIMIT Monitors)
NOV/UV_COMP Resolution, Output Voltage
Supervisors
(Note 15) 9 Bits
VOV-RNG Output OV Comparator Threshold
Detection Range
(Note 15)
High Range Scale, MFR_PWM_MODEn[1] = 0b
Low Range Scale, MFR_PWM_MODEn[1] = 1b
1
0.5
3.6
2.7
V
V
VOUSTP Output OV and UV Comparator
Threshold Programming LSB Step
Size
(Note 15)
High Range Scale, MFR_PWM_MODEn[1] = 0b
Low Range Scale, MFR_PWM_MODEn[1] = 1b
11.2
5.6
mV
mV
VOUT-RNGH Full-Scale Command Voltage, Range
High (0.5V to 3.6V)
Set Point Accuracy
Resolution
LSB Step Size
VOUTnCommanded to 3.6V, MFR_PWM_MODEn[1] = 0b
(Notes 7, 15)
3.5
–0.5
12
1.375
3.7
–0.5
V
%
Bits
mV
VOV-ACC-nOutput OV Comparator Threshold
Accuracy Channel 0 and 1
2V ≤ VVOSNSn+– VVOSNSn–≤ 3.6V, MFR_PWM_MODEn[1]=0b
0.5V ≤ VVOSNSn+– VVOSNSn–< 2.7V, MFR_PWM_MODEn[1]=1b
(Note14)
l
l
±1.5
±40
%
mV
VUV-RNG Output UV Comparator Threshold
Detection Range
High Range Scale, MFR_PWM_MODEn[1] = 0b
Low Range Scale, MFR_PWM_MODEn[1] = 1b
(Note 15)
1
0.5
3.6
2.7
V
V

LTM4680
7
Rev. B
For more information www.analog.com
ELECTRICAL CHARACTERISTICS
The ldenotes the specifications which apply over the specified internal
operating temperature range (Note 2). nis specified as each individual output channel (Note 4). TA= 25°C, VIN = 12V, RUNn= 3.3V,
EXTVCC=0, FREQUENCY_SWITCH = 350kHz and VOUTncommanded to 1.000V unless otherwise noted. Configured with factory-default
EEPROM settings and per Test Circuit 1, unless otherwise noted.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VUV-ACC-nOutput UV Comparator Threshold
Accuracy
2V ≤ VVSNSn+– VVSNSn–≤ 3.6V, MFR_PWM_MODEn[1] = 0b
0.5V ≤ VVSNSn+– VVSNSn–< 2.7V, MFR_PWM_MODEn[1] = 1b
(Note14)
l
l
±1.5
±40
%
mV
tPROP-OV Output OV Comparator Response
Times
Overdrive to 10% Above Programmed Threshold 100 µs
tPROP-UV Output UV Comparator Response
Times
Under Drive to 10% Below Programmed Threshold 100 µs
Analog OV/UV SVIN Input Voltage Supervisor Comparators (Threshold Detectors for VIN_ON and VIN_OFF)
NSVIN-OV/UV-COMP SVIN OV/UV Comparator Threshold-
Programming Resolution
(Notes 14, 15) 9 Bits
SVIN-OU-RANGE SVIN OV/UV Comparator Threshold-
Programming Range
Limited to Abs Max = 18V for LTM4680 Module 4.5 18 V
SVIN-OU-STP SVIN OV/UV Comparator Threshold-
Programming LSB Step Size
(Note 15) 76 mV
SVIN-OU-ACC SVIN OV/UV Comparator Threshold
Accuracy
4.5V < SVIN ≤ 16V l±350 mV
tPROP-SVIN-HIGH-VIN SVIN OV/UV Comparator Response
Time, High VIN Operating
Configuration
Test Circuit 1, and:
VIN_ON = 9V; SVIN Driven from 8.775V to 9.225V
VIN_OFF = 9V; SVIN Driven from 9.225V to 8.775V
l
l
100
100
µs
µs
tPROP-SVIN-LOW-VIN SVIN OV/UV Comparator Response
Time, Low VIN Operating
Configuration
Test Circuit 2, and:
VIN_ON = 4.5V; SVIN Driven from 4.225V to 4.725V
VIN_OFF = 4.5V; SVIN Driven from 4.725V to 4.225V
l
l
100
100
µs
µs
Channels 0 and 1 Output Voltage Readback (READ_VOUTn)
NVO-RB Output Voltage Readback Resolution
and LSB Step Size
(Note 15) 16
244
Bits
µV
VO-F/S Output Voltage Full-Scale Digitizable
Range
VRUNn= 0V (Note 15), Limited to 3.6V Max Operating 8 V
VO-RB-ACC-nOutput Voltage Readback Accuracy 1V ≤ VVOSNSn+ – VVOSNSn–≤ 3.3V
0.5V ≤ VVOSNSn+– VVOSNSn–< 1V
l
l
Within±0.5%of Reading
Within±5mVof Reading
tCONVERT-VO-RB Output Voltage Readback Update
Rate
MFR_ADC_CONTROL = 0x00 (Notes 9, 15)
MFR_ADC_CONTROL = 0x01 through 0x0C (Notes 9, 15)
MFR_ADC_CONTROL Section
90
8
ms
ms
ms
Input Voltage (SVIN) Readback (READ_VIN)
NSVIN-RB Input Voltage Readback Resolution
and LSB Step Size
(Notes 11, 15) Limited to Abs Max = 18V for
LTM4680Module
10
15.625
Bits
mV
SVIN-F/S Input Voltage Full-Scale Digitizable
Range
(Notes 11, 15) 43 V
SVIN-RB-ACC Input Voltage Readback Accuracy READ_VIN, 4.5V ≤ SVIN ≤ 16V lWithin ±2% of Reading
tCONVERT-SVIN-RB Input Voltage Readback Update Rate MFR_ADC_CONTROL = 0x00 (Notes 9, 15)
MFR_ADC_CONTROL = 0x01 (Notes 9, 15)
90
8
ms
ms
Channels0 and 1Output Current(READ_IOUTn),Duty Cycle(READ_DUTY_CYCLEn), andComputed InputCurrent (MFR_READ_IINn)Readback
NIO-RB Output Current Readback Resolution
and LSB Step Size
(Note 15) 10
34.1
Bits
mA
IO-F/S Output Current Full-Scale Digitizable
Range
(Note 15)
Utilizing MFR_PWM_MODE[7] = 0b,
Using IOUT_OC_FAULT_LIMIT = 40A, Page 90
30 A

LTM4680
8
Rev. B
For more information www.analog.com
ELECTRICAL CHARACTERISTICS
The ldenotes the specifications which apply over the specified internal
operating temperature range (Note 2). nis specified as each individual output channel (Note 4). TA= 25°C, VIN = 12V, RUNn= 3.3V,
EXTVCC=0, FREQUENCY_SWITCH = 350kHz and VOUTncommanded to 1.000V unless otherwise noted. Configured with factory-default
EEPROM settings and per Test Circuit 1, unless otherwise noted.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
IO-RB-ACC Output Current, Readback Accuracy READ_IOUTn, Channels 0 and 1, 0 ≤ IOUTn≤ 30A,
Forced-Continuous Mode, MFR_PWM_MODEn[0] = 1b
25°C to 125°C
–40°C to 125°C
See Histograms in Typical Performance Characteristic, (Note 12).
l
Within 0.75A of Reading
Within 1.5A of Reading
IO-RB(30A) Full Load Output Current Readback IOUTn= 30A (Note 12). See Histograms in Typical
Performance Characteristics
30 A
tCONVERT-IO-RB Output Current Readback Update
Rate
MFR_ADC_CONTROL = 0x00 (Notes 9, 15)
MFR_ADC_CONTROL = 0x06 (CH0 IOUT) or 0x0A (CH1 IOUT)
(Notes 9, 15) See MFR_ADC_CONTROL Section
90
8
ms
ms
Input Current Readback
N Resolution (Note 15) 10 Bits
VIINSTP LSB Step Size Full-Scale Range = 16mV
LSB Step Size Full-Scale Range = 32mV
LSB Step Size Full-Scale Range = 64mV
Gain = 8, 0V ≤ |VIIN+ – VIIN–| ≤ 5mV
Gain = 4, 0V ≤ |VIIN+ – VIIN–| ≤ 20mV
Gain = 2, 0V ≤ |VIIN+ – VIIN–| ≤ 50mV
15.26
30.52
61
µV
µV
µV
IIN_TUE Total Unadjusted Error Gain = 8, 2.5mV ≤ |VIIN+ – VIIN–| (Note 14)
Gain = 4, 4mV ≤ |VIIN+ – VIIN–| (Note 14)
Gain = 2, 6mV ≤ |VIIN+ – VIIN–| (Note 14)
l
l
l
±2
±1.3
±1.2
%
%
%
VOS Zero-Code Offset Voltage (Note 15) ±50 µV
tCONVERT Update Rate (Notes 9,15) See MFR_ADC_CONTROL Section for Faster
Update Rates
90 ms
Supply Current Readback
N Resolution (Note 15) 10 Bits
VICHIPSTP LSB Step Size Full-Scale Range =
256mV
Onboard 1Ω Resistor 244 µV
ICHIP_RB ICHIP Readback SVIN Current ±50 mA
tCONVERT Update Rate (Notes 9,15) See MFR_ADC_CONTROL Section for Faster
Update Rates
90 ms
Temperature Readback (T0, T1)
TRES-RB Temperature Readback Resolution Channel 0, Channel 1, and Controller (Note 15) 0.25 °C
T0_TUE External Temperature Total
Unadjusted Readback Error
Supporting Only ∆VBE Sensing
±2.5 °C
T1_TUE Internal TSNS TUE VRUN0,1 = 0.0, fSYNC = 0kHz (Note 14) ±1 °C
tCONVERT Update Rate MFR_ADC_CONTROL = 0x00 (Notes 9, 15)
MFR_ADC_CONTROL = 0x04 or 0x0C (Notes 9, 15)
90
8
ms
ms
INTVCC Regulator/EXTVCC
VINTVCC Internal VCC Voltage No Load 6V ≤ VIN ≤ 16V 5.25 5.5 5.75 V
VLDO_INT INTVCC Load Regulation ICC = 0mA to 20mA, 6V ≤ VIN ≤ 16V 0.5 ±2 %
VEXTVCC EXTVCC Switchover Voltage VIN ≥ 7V, EXTVCC Rising 4.5 4.7 V
VLDO_HYS EXTVCC Hysteresis 300 mV
VLDO_EXT EXTVCC Voltage Drop ICC = 20mA, VEXTVCC = 5.5V 70 120 mV
VIN_THR VIN Threshold to Enable EXTVCC
Switchover
VIN Rising 7 V
VIN_THF VIN Threshold to Disable EXTVCC
Switchover
VIN Falling 6.5 V

LTM4680
9
Rev. B
For more information www.analog.com
ELECTRICAL CHARACTERISTICS
The ldenotes the specifications which apply over the specified internal
operating temperature range (Note 2). nis specified as each individual output channel (Note 4). TA= 25°C, VIN = 12V, RUNn= 3.3V,
EXTVCC=0, FREQUENCY_SWITCH = 350kHz and VOUTncommanded to 1.000V unless otherwise noted. Configured with factory-default
EEPROM settings and per Test Circuit 1, unless otherwise noted.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VDD33 Regulator
VVDD33 Internal VDD33 Voltage 4.5V < VINTVCC or 4.8V < VEXTVCC 3.2 3.3 3.4 V
ILIM VDD33 Current Limit VDD33 = GND, VIN = INTVCC = 4.5V 100 mA
VVDD33_OV VDD33 Overvoltage Threshold 3.5 V
VVDD33_UV VDD33 Undervoltage Threshold 3.1 V
VDD25 Regulator
VVDD25 Internal VDD25 Voltage 2.5 V
ILIM VDD25 Current Limit VDD25 = GND, VIN = INTVCC = 4.5V 80 mA
Oscillator and Phase-Locked Loop (PLL)
fRANGE PLL SYNC Range Synchronized with Falling Edge of SYNC l300 1000 kHz
fOSC Oscillator Frequency Accuracy Frequency Switch = 250.0 to 1000.0 kHz (Note 15) l±7.5 %
VTH(SYNC) SYNC Input Threshold VSYNC Falling
VSYNC Rising
1
1.5
V
V
VOL(SYNC) SYNC Low Output Voltage ILOAD = 3mA 0.2 0.4 V
ILEAK(SYNC) SYNC Leakage Current in Slave Mode 0V ≤ VPIN ≤ 3.6V ±5 µA
θSYNC-θ0 SYNC to Ch0 Phase Relationship
Based on the Falling Edge of Sync
and Rising Edge of TG0
MFR_PWM_CONFIG[2:0] = 0,2,3
MFR_PWM_CONFIG[2:0] = 5
MFR_PWM_CONFIG[2:0] = 1
MFR_PWM_CONFIG[2:0]= 4,6
0
60
90
120
Deg
Deg
Deg
Deg
θSYNC-θ1 SYNC to Ch1 Phase Relationship
Based on the Falling Edge of Sync
and Rising Edge of TG1
MFR_PWM_CONFIG[2:0] = 3
MFR_PWM_CONFIG[2:0] = 0
MFR_PWM_CONFIG[2:0] = 2,4,5
MFR_PWM_CONFIG[2:0] = 1
MFR_PWM_CONFIG[2:0] = 6
120
180
240
270
300
Deg
Deg
Deg
Deg
Deg
EEPROM Characteristics
Endurance (Notes 13, 16) 0°C ≤ TJ≤ 85°C During EEPROM Write Operations l10,000 Cycles
Retention (Notes 13, 16) TJ< 125°C l10 Years
Mass_Write Mass Write Operation Time STORE_USER_ALL, 0°C < TJ< 85°C
During EEPROM Write Operation
440 4100 ms
Leakage Current SDA, SCL, ALERT, RUN
IOL Input Leakage Current OV ≤ VPIN ≤ 5.5V l±5 µA
Leakage Current FAULTn, PGOODn, SHARE_CLK
IGL Input Leakage Current OV ≤ VPIN ≤ 3.6V l±2 µA
Digital Inputs SCL, SDA, RUNn, FAULTn
VIH Input High Threshold Voltage l1.35 V
VIL Input Low Threshold Voltage l0.8 V
VHYST Input Hysteresis SCL, SDA 0.08 V
CPIN Input Capacitance 10 pF
Digital Input WP
IPUWP Input Pull-Up Current WP 10 µA
Open-Drain Outputs SCL, SDA, FAULTn, ALERT, RUNn, SHARE_CLK, PGOODn
VOL Output Low Voltage ISINK = 3mA 0.4 V

LTM4680
10
Rev. B
For more information www.analog.com
ELECTRICAL CHARACTERISTICS
The ldenotes the specifications which apply over the specified internal
operating temperature range (Note 2). nis specified as each individual output channel (Note 4). TA= 25°C, VIN = 12V, RUNn= 3.3V,
EXTVCC=0, FREQUENCY_SWITCH = 350kHz and VOUTncommanded to 1.000V unless otherwise noted. Configured with factory-default
EEPROM settings and per Test Circuit 1, unless otherwise noted.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Digital Inputs SHARE_CLK, WP
VIH Input High Threshold Voltage l1.5 1.8 V
VIL Input Low Threshold Voltage l0.6 1 V
Digital Filtering of FAULTn
IFLTG Input Digital Filtering FAULTn3 µs
Digital Filtering of PGOODn
IFLTG Output Digital Filtering PGOODn100 µs
Digital Filtering of RUNn
IFLTG Input Digital Filtering RUN 10 µs
PMBus Interface Timing Characteristics
fSCL Serial Bus Operating Frequency l10 400 kHz
tBUF Bus Free Time Between Stop and
Start
l1.3 µs
tHD(STA) Hold Time After Repeated Start
Condition After This Period, the First
Clock is Generated
l0.6 µs
tSU(STA) Repeated Start Condition Setup Time l0.6 10000 µs
tSU(ST0) Stop Condition Setup Time l0.6 µs
tHD(DAT) Date Hold Time
Receiving Data
Transmitting Data
l
l
0
0.3 0.9
µs
µs
tSU(DAT) Data Setup Time
Receiving Data 0.1 µs
tTIMEOUT_SMB Stuck PMBus Timer Non-Block Reads
Stuck PMBus Timer Block Reads
Measured from the Last PMBus Start Event 32
255
ms
tLOW Serial Clock Low Period l1.3 10000 µs
tHIGH Serial Clock High Period l0.6 µs
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2:The LTM4680 is tested under pulsed-load conditions such that
TJ≈TA. The LTM4680E is guaranteed to meet performance specifications
over the 0°C to 125°C internal operating temperature range. Specifications
over the –40°C to 125°C internal operating temperature range are assured
by design, characterization and correlation with statistical process
controls. The LTM4680I is guaranteed to meet specifications over the full
–40°C to 125°C internal operating temperature range. TJis calculated from
the ambient temperature TAand the power dissipation PD according the
formula:
TJ=TA+ (PD•θJA)
Note that the maximum ambient temperature consistent with these
specifications is determined by specific operating conditions in
conjunction with board layout, the rated package thermal resistance and
other environmental factors.