Rainbow Electronics MAX865 User Manual
Max865 compact, dual-output charge pump, General description, Applications
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_______________General Description
The MAX865 is a CMOS charge-pump DC-DC convert-
er in an ultra-small µMAX package. It produces positive
and negative outputs from a single positive input, and
requires only four capacitors. The charge pump first
doubles the input voltage, then inverts the doubled volt-
age. The input voltage ranges from +1.5V to +6.0V.
The internal oscillator is guaranteed to be between
20kHz and 38kHz, keeping noise above the audio
range while consuming minimal supply current. A 75
Ω
output impedance permits useful output currents up to
20mA.
The MAX865 comes in a 1.11mm-high, 8-pin µMAX
package that occupies half the board area of a stan-
dard 8-pin SOIC. For a device with selectable frequen-
cies and logic-controlled shutdown, refer to the MAX864
data sheet.
________________________Applications
Low-Voltage GaAsFET Bias in Wireless Handsets
VCO and GaAsFET Supplies
Split Supply from 3 Ni Cells or 1 Li+ Cell
Low-Cost Split Supply for Low-Voltage
Data-Acquisition Systems
Split Supply for Analog Circuitry
LCD Panels
____________________________Features
♦
1.11mm-High µMAX Package
♦
Compact: Circuit Fits in 0.08in
2
♦
Requires Only Four Capacitors
♦
Dual Outputs (positive and negative)
♦
+1.5V to +6.0V Input Voltage
♦
20kHz (min) Frequency (above the audio range)
MAX865
Compact, Dual-Output Charge Pump
________________________________________________________________
Maxim Integrated Products
1
1
2
3
4
8
7
6
5
C1+
V+
IN
GND
V-
C2-
C2+
C1-
MAX865
µ
MAX
TOP VIEW
__________________Pin Configuration
MAX865
C1+
V+
GND
GND
+V
IN
to ±2V
IN
CONVERTER
V-
IN
GND
C1-
C2+
C2-
+2*V
IN
V
IN
(+1.5V to +6.0V)
-2*V
IN
__________Typical Operating Circuit
19-0472; Rev 1; 7/97
PART
MAX865C/D
MAX865EUA
-40°C to +85°C
0°C to +70°C
TEMP. RANGE
PIN-PACKAGE
Dice
8 µMAX
______________Ordering Information
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 408-737-7600 ext. 3468.