ABRIDGED
19-0681; Rev 2; 11/07
KIT
ATION
EVALU
E
BL
AVAILA
Smallest, All-Internal MOSFET, 7-Channel
DSC PMIC in Tiny 5mm x 5mm Thin QFN
General Description
The MAX8680 highly efficient complete power-supply
solution is designed for digital still cameras (DSCs) and
digital video cameras (DVCs). The device integrates
seven on-chip power MOSFET DC-DC converters with
up to 95% efficiency to power all critical power supplies
in DSC systems. Each converter also features True
Shutdown™, as well as internal compensation to mini-
mize external component count. The seven DC-DC
converter outputs are:
• Step-up synchronous-rectified DC-DC converter
(SU). The MAX8680 is bootstrapped from V
SU
.
•
•
•
MAIN synchronous-rectified step-down DC-DC con-
verter (M) for DSP I/O supply voltage.
DDRZ synchronous-rectified step-down DC-DC
converter (Z) for DSP DDR supply voltage.
Low-voltage (down to 1V) synchronous-rectified
step-down DC-DC converter (SD) for DSP core sup-
ply voltage.
High-voltage, step-up DC-DC converter with current
regulation and PWM dimming control (LEDBST) for
white LEDs (WLED).
High-voltage step-up DC-DC converter (CCDBST)
for CCD imagers or positive LCD bias supplies.
Transformerless inverting DC-DC converter (CCDINV)
for CCD imagers or negative LCD bias supplies.
Features
♦
95% Efficient Synchronous-Rectified DC-DC
Converters
♦
90% Efficient Boost-Buck Operation
♦
85% Efficient DC-DC Converters for CCD, LCD,
WLED, and/or OLED
♦
Internal Compensation on All Channels
♦
True Shutdown on All Step-Up Converters
♦
Overload Protection
♦
Soft-Start for Controlled Startup Current
♦
Dropout Operation (100% Duty Cycle) on Step-
Down Converters
♦
Regulated Current Output for Up to 6 White LEDs
♦
PWM Dimming of WLED Current
♦
Adjustable LED Overvoltage Protection Up to 27V
♦
Transformerless Inverting Converter for CCD
♦
2MHz Switching Frequency for Low-Voltage
Channels
♦
±2.5% Switching Frequency Accuracy
♦
1µA Shutdown Supply Current
♦
Power-On Voltage Tracking for Core and Main
Outputs
♦
All Internal Power MOSFETs
♦
SDOK
Power-OK Indicator
MAX8680
•
•
•
The MAX8680 has an independent/simultaneous
power-on sequence of the CCDBST and CCDINV con-
verters. For a preset power-on sequence of CCDBST
before CCDINV, contact the factory.
The MAX8680 operates with 1-cell lithium-ion (Li+) bat-
tery, two-AA cell, or dual-battery designs and is avail-
able in a 5mm x 5mm, 40-pin thin QFN package. The
MAX8680 operates over the -40°C to +85°C extended
temperature range.
Typical Operating Circuit
INPUT
2.7V TO 5.5V
SU STEP-UP
MAIN STEP-DOWN
SD STEP-DOWN
DDRZ STEP-DOWN
V
SU
5V
V
MAIN
3.3V
V
SD
1.8V
V
DDRZ
2.5V
BATT
ONSU
ONM
ONSD
ONZ
Applications
DSCs and DVCs
PDAs and Portable Media Players
GPS Navigation Systems
MAX8680
SDOK
ONLED
ONBST
ONINV
LEDBST
CCDBST
CCDINV
V
LEDBST
UP TO 6 WLEDs
V
CCDBST
+15V
V
CCDINV
-7.5V
Ordering Information
PART
MAX8680ETL+
TEMP
RANGE
-40°C to
+85°C
PIN-PACKAGE
40 Thin QFN-EP*
5mm x 5mm x 0.8mm
PKG
CODE
T4055-2
+Denotes
a lead-free package.
*EP=
Exposed paddle.
Pin Configuration appears at the end of data sheet.
True Shutdown is a trademark of Maxim Integrated Products, Inc.
1
________________________________________________________________
Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim's website at www.maxim-ic.com.
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