MAX1800 Datasheet, PDF (1/24 Pages) Maxim Integrated Products – Digital Camera Step-Up Power Supply

19-1833; Rev 0; 10/00
EVAALVUAAILTAIOBNLEKIT
Digital Camera Step-Up
Power Supply
General Description
The MAX1800 provides a complete power-supply solu-
tion for digital still cameras and video cameras. The
device integrates a high-efficiency main step-up DC-DC
converter, three auxiliary step-up controllers, and an
uncommitted gain block that drives an external P-channel
MOSFET for a linear regulator. The MAX1800 is targeted
for applications that use either two or three primary cells
or a single lithium-ion (Li+) battery.
The main DC-DC converter accepts inputs from +0.7V to
+5.5V and regulates a resistor-adjustable output from
2.7V to 5.5V. It uses an internal synchronous rectifier to
regulate the output with 95% efficiency. An adjustable
operating frequency facilitates designs for optimum size,
cost, and efficiency.
The auxiliary step-up controllers can be used to power a
digital camera’s CCD, LCD, and backlight. The MAX1800
also features expandability by supplying power, oscillator
signal, and reference to the MAX1801, a low-cost slave
DC-DC controller that supports step-up, SEPIC, and fly-
back configurations.
The MAX1800 is available in a space-saving 32-pin TQFP
package (5mm x 5mm body), and the MAX1801 is avail-
able in an 8-pin SOT package. An evaluation kit
(MAX1800EVKIT) featuring both devices is available to
expedite designs.
________________________Applications
Digital Still Cameras
Digital Video Cameras
PDAs
DVD Players
Hand-Held Devices
Internet Access Tablets
Features
o +0.7V to +5.5V Input Voltage Range
o Main DC-DC Converter
95% Efficiency
+2.7V to +5.5V Adjustable Output Voltage
1.5A Load Current
o Uncommitted Gain Block for Linear Regulator
o Three Independent Auxiliary Step-Up Controllers
Adjustable Maximum Duty Cycle
o Oscillator and Reference Outputs to Drive External
Slave Controllers (MAX1801)
o Power-Ready Output
o Up to 1MHz Switching Frequency
o 1µA Supply Current in Shutdown Mode
o Internal Soft-Start Control
o Overload Protection for all DC-DC Converters
o Compact 32-Pin TQFP Package (5mm x 5mm body)
PART
MAX1800EHJ
Ordering Information
TEMP. RANGE
-40°C to +85°C
PIN-PACKAGE
32 TQFP
TOP VIEW
Pin Configuration
32 31 30 29 28 27 26 25
Typical Operating Circuit
INPUT
0.7V TO 5.5V
MAX1800
MASTER
CCD
TFT
CCFL
CORE
MAIN
OSC
REF
MAX1801
SLAVE
MOTOR
PGND 1
DL1 2
ON1 3
FB1 4
COMP1 5
DCON1 6
POUT 7
DL2 8
MAX1800
24 ONM
23 RDYM
22 POUT
21 LX
20 LX
19 PGND
18 COMPM
17 FBM
9 10 11 12 13 14 15 16
TQFP
________________________________________________________________ Maxim Integrated Products 1
For price, delivery, and to place orders, please contact Maxim Distribution at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.