Rainbow Electronics MAX861 - Manual

_______________General Description
The MAX860/MAX861 charge-pump voltage converters
invert input voltages ranging from +1.5V to +5.5V, or
double input voltages ranging from +2.5V to +5.5V.
Because of their high switching frequencies, these
devices use only two small, low-cost capacitors. Their
50mA output makes switching regulators unnecessary,
eliminating inductors and their associated cost, size,
and EMI. Greater than 90% efficiency over most of the
load-current range, combined with a typical operating
current of only 200µA (MAX860), provides ideal perfor-
mance for both battery-powered and board-level volt-
age-conversion applications.
A frequency-control (FC) pin provides three switching-
frequencies to optimize capacitor size and quiescent
current and to prevent interference with sensitive cir-
cuitry. Each device has a unique set of three available
frequencies. A shutdown (S
—
H
—
D
—
N
–
) pin reduces current
consumption to less than 1µA. The MAX860/MAX861
are suitable for use in applications where the ICL7660
and MAX660's switching frequencies are too low. The
MAX860/MAX861 are available in 8-pin µMAX and
SO packages.
________________________Applications
Portable Computers
Medical Instruments
Interface Power Supplies
Hand-Held Instruments
Operational-Amplifier Power Supplies
____________________________Features
♦ 8-Pin, 1.11mm High µMAX Package
♦ Invert or Double the Input Supply Voltage
♦ Three Selectable Switching Frequencies
♦ High Frequency Reduces Capacitor Size
♦ 87% Efficiency at 50mA
♦ 200µA Quiescent Current (MAX860)
♦ 1µA Shutdown Supply Current
♦ 600mV Voltage Drop at 50mA Load
♦ 12
Ω
Output Resistance
______________Ordering Information
MAX860/MAX861
50mA, Frequency-Selectable,
Switched-Capacitor Voltage Converters
________________________________________________________________ Maxim Integrated Products 1
1
2
3
4
8
7
6
5
V DD
SHDN
LV
OUT C1-
GND
C1+
FC
MAX860
MAX861
SO/
µ
MAX
TOP VIEW
__________________Pin Configuration
1
2
3
4
8
7
6
5
FC
C1+
GND
C1- OUT
LV
SHDN
V DD
MAX860
MAX861
1
2
3
4
8
7
6
5
FC
C1+
GND
C1- OUT
LV
SHDN
V DD
MAX860
MAX861
INPUT
VOLTAGE
+1.5V TO +5.5V
INVERTED
NEGATIVE
OUTPUT
INPUT
VOLTAGE
+2.5V TO +5.5V
DOUBLED
POSITIVE
OUTPUT
10 µ F
10 µ F
10 µ F
10 µ F
C1
C1
C2
C2
VOLTAGE INVERTER
POSITIVE VOLTAGE DOUBLER
__________Typical Operating Circuit
19-0239; Rev 1; 11/96
PART
MAX860 ISA
MAX860IUA -25°C to +85°C
-25°C to +85°C
TEMP. RANGE PIN-PACKAGE
8 SO
8 µMAX
* Dice are tested at T A = +25°C, DC parameters only.
† Contact factory for availability.
MAX860C/D 0°C to +70°C Dice*
MAX860ESA -40°C to +85°C 8 SO
MAX860MJA -55°C to +125°C 8 CERDIP†
MAX861 ISA -25°C to +85°C 8 SO
MAX861IUA -25°C to +85°C 8 µMAX
MAX861C/D 0°C to +70°C Dice*
MAX861ESA -40°C to +85°C 8 SO
MAX861MJA -55°C to +125°C 8 CERDIP†
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800