Rainbow Electronics MAX1801 User Manual
General description, Applications features, Typical operating circuit
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General Description
The MAX1801 step-up slave DC-DC controller is used
with either the MAX1800 (step-up) or the MAX1802 (step-
down) master DC-DC converter to provide a complete
power-supply solution for digital still and digital video
cameras. By using the master converter’s reference volt-
age and oscillator, the size and the cost of the slave con-
troller are reduced and all converters are guaranteed to
switch at the same frequency.
The MAX1801 drives an external N-channel MOSFET
and can be used in step-up, single-ended primary
inductance converter (SEPIC), and flyback topologies. If
extra supplies are required for a new design, slave con-
trollers can be added to an existing master circuit with
minimal redesign, saving both cost and time. The
MAX1801 features a built-in soft-start, short-circuit pro-
tection, and an adjustable duty-cycle limit.
The MAX1801 is available in a space-saving 8-pin
SOT23 package. Separate evaluation kits combining the
MAX1800/MAX1801 (MAX1800EVKIT) and MAX1802/
MAX1801 (MAX1802EVKIT) are available to expedite
designs.
________________________Applications
Features
♦ Provides Simple Expandability for the MAX1800
and MAX1802 Master Converters
♦ Operates in Step-Up, SEPIC, and Flyback
Topologies
♦ 100kHz to 1MHz Adjustable Operating Frequency
♦ Duty-Cycle Limit Adjustable from 40% to 90%
♦ Soft-Start
♦ Short-Circuit Protection
♦ 0.01µA Supply Current in Shutdown Mode
♦ Tiny 8-Pin SOT23 Package
MAX1801
Digital Camera Step-Up Slave
DC-DC Controller
________________________________________________________________ Maxim Integrated Products
1
Typical Operating Circuit
19-1741 Rev 0; 10/00
Ordering Information
Pin Configuration appears at end of data sheet.
8 SOT23-8
PIN-PACKAGE
TEMP. RANGE
-40°C to +85°C
MAX1801EKA-T
PART
MAX1801
DL
FB
COMP
GND
REF
1.25V
2.2V TO 5.5V
IN
OSC
DCON
BATTERY
0.7V TO V
OUT
V
OUT
MAX1800
OR
MAX1802
Digital Still Cameras
Digital Video Cameras
Portable DVD Players
Internet Access Tablets
PDAs
Hand-Held Devices
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.