19-1794 Rev 0; 10/00
Compact, High-Efficiency, Dual-Output
Step-Up DC-DC Converter
The MAX1817 is a compact, high-efficiency, dual-out-
put step-up converter for portable devices that pro-
vides both the main logic supply and the LCD bias. The
device operates from an input voltage of +1.5V to
+5.5V, allowing the use of 2- or 3-cell alkaline batteries,
or 1-cell lithium-ion (Li+) batteries.
The MAX1817’s main regulator supplies 125mA at
either a preset 3.3V or an adjustable 2.5V to 5.5V out-
put voltage with up to 88% efficiency. A 0.1µA shut-
down state also minimizes battery drain. The
MAX1817’s secondary step-up converter provides the
LCD bias voltage and is adjustable up to +28V.
Other features include a fast switching frequency to
reduce the size of external components and a low qui-
escent current to maximize battery life. Both outputs can
be independently shut down for improved flexibility.
The MAX1817 is supplied in a compact 10-pin µMAX
package. The MAX1817 evaluation kit (MAX1817EVKIT)
is available to speed up design.
o Dual Step-Up Converter in a Tiny 10-Pin µMAX
o Main Output
Up to 125mA Load Current
Fixed 3.3V or Adjustable 2.5V to 5.5V
Up to 88% Efficiency
o LCD Output
Up to 28V for LCD Bias
o Input Voltage Range +1.5V to +5.5V
o Minimal External Components Required
o 0.1µA Logic-Controlled Shutdown
o Low 15µA Quiescent Supply Current
-40°C to +85°C
Typical Operating Circuit
________________________________________________________________ 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.