Rainbow Electronics MAX8715 - Manual

General Description
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 0.21
Ω/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.
Applications
LCD Displays
PCMCIA Cards
Portable Applications
Hand-Held Devices
Features
♦ 90% Efficiency
♦ Adjustable Output from V IN to 12V
♦
1.6A, 0.21
Ω
, 14V Power MOSFET (MAX1790)
♦ 2.4A, 0.15 Ω , 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
Low-Noise Step-Up DC-DC Converters
________________________________________________________________ Maxim Integrated Products 1
IN
LX GND
1
2
8
7
SS
FREQ FB
COMP
µ MAX
TOP VIEW
3
4
6
5
MAX1790
MAX8715
SHDN
LX
IN
V IN
2.6V TO 5V
GND
FREQ
V OUT
COMP
SHDN
FB
MAX1790
MAX8715
ON/OFF
SS
Typical Operating Circuit
19-1563; Rev 2; 5/04
Pin Configuration
Ordering Information
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.
EVALUATION KIT
AVAILABLE
PART TEMP RANGE PIN-PACKAGE
MAX1790 EUA -40°C to +85°C 8 µMAX
MAX8715 EUA -40°C to +85°C 8 µMAX
µMAX is a registered trademark of Maxim Integrated Products,
Inc.