MAX1795/MAX1796/
MAX1797
Low-Supply Current, Step-Up DC-DC Converters
with True Shutdown
General Description
Features
● > 95% Efficiency
The MAX1795/MAX1796/MAX1797 are high-efficiency,
step-up DC-DC converters intended for small portable
hand-held devices. These devices feature Maxim’s True
Shutdown™ circuitry, which fully disconnects the out-
put from the input in shutdown, improves efficiency,
and eliminates costly external components. All three
devices also feature Maxim’s proprietary LX-damping
circuitry for reduced EMI in noise-sensitive applications.
For additional in-system flexibility, a battery monitoring
comparator (LBI/LBO) remains active even when the
DC-DC converter is in shutdown.
● True-Shutdown Circuitry
• Output Disconnects from Input in Shutdown
• No External Schottky Diode Needed
● 25μA Quiescent Supply Current
● Low-Noise Antiringing Feature
● LBI/LBO Comparator Enabled in Shutdown
● 2μA Shutdown Current
● 8-Pin μMAX Package
The input voltage range is +0.7V to V
, where V
OUT
OUT
Ordering Information
can be set from +2V to +5.5V. Startup is guaranteed
from +0.85V. The MAX1795/MAX1796/MAX1797 have a
preset, pin-selectable 5V or 3.3V output. The output can
also be adjusted to other voltages, using two external
resistors. The three devices differ only in their current
limits, allowing optimization of external components for
different loads: The MAX1795, MAX1796, and MAX1797
have current limits of 0.25A, 0.5A, and 1A, respectively.
All devices are packaged in a compact, 8-pin μMAX
package that is only 1.09mm tall and half the size of an
8-pin SO.
PART
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
8 μMAX
MAX1795EUA
MAX1796EUA
MAX1797EUA
8 μMAX
8 μMAX
Applications
● Portable Digital Audio Players
● PDAs/Palmtops
● Wireless Handsets
● Portable Terminals
Pin Configuration
Typical Operating Circuit
IN
0.7V TO
5.5V
TOP VIEW
BATT
LX
LBI
FB
1
2
3
4
8
7
6
5
BATT
OUT
LX
MAX1795
MAX1796
MAX1797
OUT
FB
OUT
MAX1795
MAX1796
MAX1797
LBI
LBO
LBO
GND
SHDN
OFF
SHDN
µMAX
ON
GND
True Shutdown is a trademark of Maxim Integrated Products.
19-1798; Rev 0; 12/00