LTC3882_15 Datasheet, PDF (1/104 Pages) Linear Technology – Dual Output PolyPhase Step-Down DC/DC Voltage Mode Controller with Digital Power System Management

LTC3882
Dual Output PolyPhase
Step-Down DC/DC Voltage Mode Controller
with Digital Power System Management
FEATURES
n _PMBus/I²_{C Compliant Serial Interface}
– Monitor Voltage, Current, Temperature and Faults
– Digitally Programmable Voltage, Current Limit,
Soft-Start/Stop, Sequencing, Margining, AVP
and UV/OV Thresholds
n _{3V ≤ VINSNS ≤ 38V, 0.5V ≤ VOUT ≤ 5.25V}
n _{±0.5% Output Voltage Accuracy}
n _{Programmable PWM Frequency or External Clock}
Synchronization from 250kHz to 1.25MHz
n _{Accurate PolyPhase}^® _{Current Sharing}
n _{Internal EEPROM with Fault Logging}
n _{IC Supply Range: 3V to 13.2V}
n _{Resistor or Inductor DCR Current Sensing}
n _{Optional Resistor Programming for Key Parameters}
n _{40-Pin (6mm × 6mm) QFN Package}
APPLICATIONS
n _{High Current Distributed Power Systems}
n _{Servers, Network and Storage Equipment}
n _{Intelligent Energy Efficient Power Regulation}
n _{Industrial/Telecom/ATE Systems}
DESCRIPTION
The LTC^®3882 is a dual, PolyPhase DC/DC synchronous
step-down switching regulator controller with PMBus
compliant serial interface. It uses a constant frequency,
leading-edge modulation, voltage mode architecture for
excellent transient response and output regulation. Each
PWM channel can produce output voltages from 0.5V to
5.25V using a wide range of 3.3V compatible power stages,
including power blocks, DrMOS or discrete FET drivers.
Up to four LTC3882s can operate in parallel for 2-, 3-, 4-,
6- or 8-phase operation.
LTC3882 system configuration and monitoring is supported
by the LTpowerPlay™ software tool. The device’s serial
interface can be used to read back input voltage, output
voltage and current, temperature and fault status. A wide
range of operating parameters can be set via the digital
interface or stored in internal EEPROM for use at power
up. Switching frequency and phase, output voltage and
device address can also be programmed using external
configuration resistors.
L, LT, LTC, LTM, Linear Technology,the Linear logo and PolyPhase are registered trademarks
and LTpowerPlay is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners. Protected by U.S. Patents, including 5396245, 5859606,
6144194, 6937178, 7420359 and 7000125.
TYPICAL APPLICATION
V_IN
7V TO 13.2V
TO/FROM
MCU
TO/FROM
EXTERNAL DEVICES
TO/FROM OTHER
OTHER PHASES
V_CC VINSNS _VSENSE0+
FB0
LTC3882
SDA
SCL
ALERT
RUN0
RUN1
WP
GPIO0
GPIO1
SHARE_CLK
SYNC
I_AVG0
I_AVG1
COMP0
COMP1
PWM0
TSNS0
I_SENSE0+
I_SENSE0–
V_SENSE1+
I_SENSE1–
I_SENSE1+
PWM1
I_{AVG_GND}
GND
TSNS1
V_SENSE0–
FDMF5820A
V_IN
PWM
SW
GND
V_OUT
1V
80A
V_IN ^FDMF5820A _SW
PWM _GND
INDUCTORS: COOPER FP1007R1-R22
SOME DETAILS OMITTED FOR CLARITY
3882 TA01a
For more information www.linear.com/LTC3882
Efficiency and Power Loss vs
Load Current
92
13
91
90
11
89
88
9
87
86
7
85
84
5
83
82
V_IN = 12V
3
81
V_OUT = 1V
SYNC = 500kHz
80
1
0 10 20 30 40 50 60 70 80
LOAD CURRENT (A)
3882 TA01b
3882f
1