SMB112
Preliminary Information
SUMMIT Microelectronics, Inc. 2005
1717 Fox Drive San Jose CA 95131
Phone 408 436-9890 FAX 408 436-9897
http://www.summitmicro.com/
2101 2.4 5/3/2005
1
INTRODUCTION
Digital programming of all major parameters via I
2
C
interface and non-volatile memory
o Output voltage set-point
o Individual dimming
o Output power-up/down sequencing
o Digital soft-start and output slew rate
o Input/Battery voltage monitoring
o UV/OV monitoring of all outputs
o Enable/Disable outputs independently
Five output channels
o One synchronous step-down (buck) channel
o Two step-up (boost) channels
o One inverting (buck-boost) channel
o
One fixed output +3.3V LDO
+2.7V to +6.0V Input Range
Highly accurate reference and output voltage (<0.5%)
with Active DC Output Control (ADOCTM) technology
Supports multiple strings of up to 12 white LEDs in
series
Undervoltage Lockout (UVLO) with hysteresis
800 kHz operating frequency
96 bytes of user configurable nonvolatile memory
Applications
White LED backlighting
High-power LED driving
TFT/LCD Displays/Monitors/TV's
Digital camcorders/still cameras
Portable DVD/MP3/GPS
Camera/smart phones
Mobile Computing/PDA's
The SMB112 is a highly integrated and flexible five-channel
power manager designed for powering TFT/LCD display
panels and for driving low- and high-power white-LEDs. The
built-in digital programmability allows system designers to
custom tailor the device to suit almost any multi-channel power
supply application from digital camcorders to mobile phones.
The SMB112 integrates all the essential blocks required to
implement a complete five-channel power subsystem for
TFT/LCD panels including a synchronous step-down "buck"
controller, two step-up "boost" controllers, one inverting "buck-
boost" controller and one fixed output +3.3V LDO. Additionally
sophisticated power control/monitoring functions required by
complex systems are built-in. These include digitally
programmable output voltage set point, individual dimming,
power-up/down sequencing, enable/disable, margining and
UV/OV/input/output monitoring on all channels.
The integration of features and built-in flexibility of the SMB112
allows the system designer to create a "platform solution" that
can be easily modified via software without major hardware
changes. Combined with the re-programmability of the
SMB112 this facilitates rapid design cycles and proliferation
from a base design to future generations of product.
The SMB112 is suited to battery-powered applications with an
input range of +2.7V to +6.0V. Output voltages are extremely
accurate (<0.5%) employing proprietary ADOCTM technology.
Communication is via the industry standard I
2
C bus. All user-
programmed settings are stored in non-volatile EEPROM of
which 96 bytes may be used for general-purpose memory
applications. The operating temperature range is 0C to +70C
and the available package is a lead-free, Green, RoHS
compliant, 32-pad QFN-32.
SIMPLIFIED APPLICATIONS DRAWING
FEATURES & APPLICATIONS
Five-Channel Digitally Programmable White-LED and TFT/LCD Power Manager
Figure 1: Applications schematic featuring the SMB112 Five-channel, programmable DC-DC controller
Note: This is an applications example only. Some pins, components and values are not shown.
SMB112
-0.8V to -10 x Vin (Prog.) @ up to 1A
Vin to 10 x Vin (Prog.) @ up to 1A
+2.7V to +6.0V
or
Li-Ion
CONTROLLER
LED Drive
VGL
MCU/RTC
I2C/SMBus
LDO
Step-Down
(Buck)
Channels
Inverter
Channel
System
Control and
Monitoring
Reset Output
Power Good
Reset Input
Vin to 10 x Vin (Prog.) @ up to 1A
VGH
2 Step-Up
(Boost)
Channels
+0.8V to 0.9 x Vin (Prog.) @ 2A
+3.3V @ 20mA
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