19-1563; Rev 3; 9/05
IT
TION K
VALUA
E
BLE
AVAILA
Low-Noise Step-Up DC-DC Converters
General Description
Features
♦
90% Efficiency
♦
Adjustable Output from V
IN
to 12V
♦
1.6A, 0.21Ω, 14V Power MOSFET (MAX1790)
♦
2.4A, 0.15Ω, 14V Power MOSFET (MAX8715)
♦
+2.6V to +5.5V Input Range
♦
Pin-Selectable 640kHz or 1.2MHz Switching
Frequency
♦
0.1µA Shutdown Current
♦
Programmable Soft-Start
♦
Small 8-Pin µMAX Package
MAX1790/MAX8715
The MAX1790/MAX8715 boost converters incorporate
high-performance (at 1.2MHz), current-mode, fixed-fre-
quency, pulse-width modulation (PWM) circuitry with a
built-in 0.21Ω/0.15Ω n-channel MOSFET to provide a high-
ly efficient regulator with fast response.
High switching frequency (640kHz or 1.2MHz selectable)
allows easy filtering and faster loop performance. An
external compensation pin provides the user flexibility in
determining loop dynamics, allowing the use of small, low
equivalent-series-resistance (ESR) ceramic output capaci-
tors. The device can produce an output voltage as high as
12V from an input as low as 2.6V.
Soft-start is programmed with an external capacitor, which
sets the input-current ramp rate. In shutdown mode, cur-
rent consumption is reduced to 0.1µA. The MAX1790/
MAX8715 are available in a space-saving 8-pin µMAX
®
package. The ultra-small package and high switching fre-
quency allow the total solution to be less than 1.1mm high.
µMAX is a registered trademark of Maxim Integrated Products,
Inc.
Ordering Information
PART
MAX1790EUA
MAX1790EUA+
MAX8715EUA
MAX8715EUA+
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
8 µMAX
8 µMAX
8 µMAX
8 µMAX
Applications
LCD Displays
PCMCIA Cards
Portable Applications
Hand-Held Devices
+
Denotes lead-free package.
Typical Operating Circuit
V
IN
2.6V TO 5V
Pin Configuration
TOP VIEW
COMP
IN
ON/OFF
SHDN
1
2
3
8
7
SS
FREQ
IN
LX
V
OUT
LX
FB
SHDN
MAX1790
MAX8715
FREQ
GND
MAX1790
MAX8715
6
5
GND
4
μMAX
SS
COMP
FB
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
