19-1439; Rev 2; 4/04
SOT23, Switched-Capacitor
Voltage Inverters with Shutdown
General Description
Features
The ultra-small MAX1719/MAX1720/MAX1721 monolithic,
CMOS charge-pump inverters accept input voltages
ranging from +1.5V to +5.5V. The MAX1720 operates at
12kHz, and the MAX1719/MAX1721 operate at 125kHz.
High efficiency, small external components, and logic-
controlled shutdown make these devices ideal for both
battery-powered and board-level voltage conversion
applications.
♦ 1nA Logic-Controlled Shutdown
♦ 6-Pin SOT23 Package
♦ 99.9% Voltage Conversion Efficiency
♦ 50µA Quiescent Current (MAX1720)
♦ +1.5V to +5.5V Input Voltage Range
♦ 25mA Output Current
Oscillator control circuitry and four power MOSFET
switches are included on-chip. A typical MAX1719/
MAX1720/MAX1721 application is generating a -5V
supply from a +5V logic supply to power analog circuitry.
All three parts come in a 6-pin SOT23 package and can
deliver a continuous 25mA output current.
♦ Requires Only Two 1µF Capacitors
(MAX1719/MAX1721)
For pin-compatible SOT23 switched-capacitor voltage
inverters without shutdown (5-pin SOT23), see the
MAX828/MAX829 and MAX870/MAX871 data sheets. For
applications requiring more power, the MAX860/MAX861
Ordering Information
deliver up to 50mA. For regulated outputs (up to -2 x V ),
IN
refer to the MAX868. The MAX860/MAX861 and MAX868
are available in space-saving µMAX packages.
PIN-
SOT
PART
TEMP RANGE
PACKAGE TOP MARK
MAX1719EUT -40°C to +85°C 6 SOT23-6
MAX1720EUT -40°C to +85°C 6 SOT23-6
MAX1721EUT -40°C to +85°C 6 SOT23-6
AACA
AABS
AABT
Applications
Local Negative Supply from a Positive Supply
Small LCD Panels
GaAs PA Bias Supply
Handy-Terminals, PDAs
Battery-Operated Equipment
Pin Configuration
Typical Operating Circuit
1µF
TOP VIEW
OUT
IN
1
2
3
C1+
6
5
4
C1+
C1-
OUT
NEGATIVE
OUTPUT
INPUT
1.5V to 5.5V
IN
-1 · V
IN
MAX1719
MAX1720
MAX1721
SHDN (SHDN)
GND
25mA
MAX1721
1µF
C1-
SHDN
ON
OFF
GND
SOT23-6
( ) ARE FOR MAX1719
________________________________________________________________ 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.