LTC3676/LTC3676-1
1
3676fe
For more information www.linear.com/LTC3676
TYPICAL APPLICATION
FEATURES DESCRIPTION
Power Management Solution
for Application Processors
The LT C
®
3676 is a complete power management solution
for advanced portable application processor-based sys-
tems. The
device contains four synchronous step-down
DC/DC
converters for core, memory, I/O, and system
on-chip (SoC) rails and three 300mA LDO regulators for
low noise analog supplies. The LTC3676-1 has a ±1.5A
buck regulator configured to support DDR termination
plus a VTTR reference output. An I
2
C serial port is used
to control regulator enables, power-down sequencing,
output voltage levels, dynamic voltage scaling, operating
modes and status reporting.
Regulator start-up is sequenced by connecting outputs to
enable pins in the desired order or via the I
2
C port. System
power-on, power-off and reset functions are controlled by
pushbutton interface, pin inputs, or I
2
C.
The LTC3676 supports i.MX, PXA and OMAP processors
with eight independent rails at appropriate power levels.
Other features include interface signals such as the VSTB
pin that toggles between programmed run and standby
output voltages on up to four rails simultaneously. The
device is available in a 40-lead 6mm 6mm QFN and
48-lead exposed pad LQFP packages.
Start-Up Sequence
APPLICATIONS
n
Quad I
2
C Adjustable High Efficiency Step Down
DC/DC Converters: 2.5A, 2.5A, 1.5A, 1.5A
n
Three 300mA LDO Regulators (Tw o Adjustable)
n
DDR Power Solution with V
TT
and VTTR Reference
n
Pushbutton ON/OFF Control with System Reset
n
Independent Enable Pin-Strap or I
2
C Sequencing
n
Programmable Autonomous Power-Down Control
n
Dynamic Voltage Scaling
n
Power Good and Reset Functions
n
Selectable 2.25MHz or 1.12MHz Switching Frequency
n
Always Alive 25mA LDO Regulator
n
12µA Standby Current
n
Low Profile 40-Lead 6mm 6mm QFN and 48-Lead
Exposed Pad LQFP
n
Supports Freescale i.MX6, ARM Cortex, and Other
Application Processors
n
Handheld Instruments and Scanners
n
Portable Industrial and Medical Devices
n
Automotive Infotainment
n
High End Consumer Devices
n
Multi-Rail Systems
L, LT , LT C , LT M , Linear Technology, the Linear logo and Burst Mode are registered trademarks
of Analog Devices, Inc. All other trademarks are the property of their respective owners.
1µF 47µF
V
RTC
3V
25mA
V
ARM
1.38V
2.5A
LDO1 SW3
LTC3676-1
GND
V
IN
2.7V TO 5.5V
V
IN
1.5µH
1µF 47µF
V
DD(HIGH)
2.97V
300mA
V
SOC
1.38V
1.5A
LDO2 SW2
1.5µH
1µF 47µF
V
LDO3
1.8V
300mA
V
DDR
(V
DDQ
)
1.5V
2.5A
LDO3 SW4
1.5µH
1µF
6
47µF
3V
300mA
V
TT
1/2 V
DDQ
1.5A
VTTR (1/2 V
DDQ
)
WAKE
TO µPROCESSOR
3676 TA01a
LDO4 SW1
ENABLES
PWR_ON
ON
VTTR
WAKE
PGOOD
I
2
C
1.5µH
2
WAKE
1ms/DIV
V
DD(HIGH)
V
ARM
AND V
SOC
V
TT
AND V
TTR
V
LDO3
V
DDR
3676 TA01b
5V/DIV
1V/DIV
1V/DIV
