50mA, Frequency-Selectable,
Switched-Capacitor Voltage Converters
____________________________Typical Operating Characteristics (continued)
(All curves generated using the inverter circuit shown in the
Typical Operating Circuits
with LV = GND and T
A
= +25°C, unless other-
wise noted. Test results also valid for doubler mode with LV = OUT and T
A
= +25°C. All capacitor values used are those recom-
mended in Table 3, unless otherwise noted. The output resistance curves represent the resistance of the device itself, which is R
O
in
the equation for R
OUT
shown in the
Capacitor Selection
section.)
MAX861
OUTPUT CURRENT vs. CAPACITANCE
HIGH-FREQUENCY MODE
MAX860-10
MAX860/MAX861
MAX861
OUTPUT CURRENT vs. CAPACITANCE
MEDIUM-FREQUENCY MODE
70
OUTPUT CURRENT (mA)
60
50
40
30
20
10
0
V
IN
= +3V, V
OUT
= -2.7V
V
IN
= +3V,
V
OUT
= -2.4V
V
IN
= +4.5V,
V
OUT
= -4V
f
OSC
= 100kHz
FC = GND
LV = GND
INVERTER MODE
V
IN
= +4.5V,
V
OUT
= -3.5V
MAX860-11
90
80
OUTPUT CURRENT (mA)
70
60
50
40
30
20
10
0
0.33
1
2.2
4.7
10
V
IN
= +3V, V
OUT
= -2.7V
V
IN
= +4.5V, V
OUT
= -4V
V
IN
= +3V, V
OUT
= -2.4V
f
OSC
= 250kHz
FC = OUT
LV = GND
INVERTER MODE
80
V
IN
= +4.5V,
V
OUT
= -3.5V
22
0.33
1
2.2
4.7
10
22
CAPACITANCE (µF)
CAPACITANCE (µF)
______________________________________________________________Pin Description
FUNCTION
PIN
1
2
3
4
5
6
7
8
NAME
INVERTER
FC
C1+
GND
C1-
OUT
LV
— —
–— –
SHDN
V
DD
Frequency Control, see Table 1
Flying-Capacitor Positive Terminal
Ground
Flying-Capacitor Negative Terminal
Negative Output
Low-Voltage-Operation Input. Connect to GND.
Active-Low Shutdown Input. Connect to V
DD
if not
used. Connect to GND to disable the charge pump.
Positive Input Supply
DOUBLER
Frequency Control, see Table 1
Flying-Capacitor Positive Terminal
Positive Input Supply
Flying-Capacitor Negative Terminal
Ground
Low-Voltage-Operation Input. Connect to OUT.
Active-Low Shutdown Input. Connect to GND pin if not
used. Connect to OUT to disable the charge pump.
Doubled Positive Output
_______________________________________________________________________________________
5
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
