50mA, Frequency-Selectable,
Switched-Capacitor Voltage Converters
MAX860/MAX861
__________________________________________Typical Operating Characteristics
(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.)
OUTPUT VOLTAGE DROP FROM
SUPPLY VOLTAGE vs. LOAD CURRENT
MAX860-01
PERCENTAGE FREQUENCY CHANGE (%)
(FROM FREQUENCY MEASURED WITH V
DD
= +5V)
OSCILLATOR FREQUENCY vs.
SUPPLY VOLTAGE
MAX860-02
OUTPUT SOURCE RESISTANCE (R
O
) vs.
SUPPLY VOLTAGE
OUTPUT SOURCE RESISTANCE (Ω)
18
16
14
12
10
8
6
4
2
0
ALL FREQUENCIES
0
1
2
3
4
5
MAX860-03
0.8
0.7
0.6
V
OUT
DROP (V)
0.5
0.4
0.3
0.2
0.1
0
0
2
0
-2
-4
-6
-8
ALL FREQUENCIES
V
DD
= +1.5V
V
DD
= +2.5V
20
V
DD
= +3.5V
V
DD
= +4.5V, +5.0V
V
DD
= +5.5V
10
20
30
40
50
-10
-12
ALL FREQUENCIES,
LV CONNECTED TO GND
(INVERTER) OR OUT (DOUBLER)
-14
1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5
SUPPLY VOLTAGE (V)
LOAD CURRENT (mA)
SUPPLY VOLTAGE (V)
OUTPUT SOURCE RESISTANCE (R
O
) vs.
TEMPERATURE
OUTPUT SOURCE RESISTANCE (Ω)
ALL FREQUENCIES
28
24
20
16
12
8
4
0
-60 -40 -20 0
20 40 60 80 100 120 140
TEMPERATURE (°C)
V
DD
= +5V
V
DD
= +1.5V
V
DD
= +3V
EFFICIENCY (%)
MAX860-04
MAX860
EFFICIENCY vs. LOAD CURRENT
MAX860-05
MAX860 SUPPLY CURRENT
vs. SUPPLY VOLTAGE
FC = V
DD
400
DOUBLER, LV = OUT
SUPPLY CURRENT (µA)
MAX860-06
32
100
90
80
70
60
50
40
30
20
10
0
0.01
0.1
1
10
INVERTER
FC = V
DD
V
DD
= +1.5V
V
DD
= +3V
V
DD
= +5V
500
300
INVERTER, LV = GND
(V
DD
> 3V)
200
100
0
100
0
1
2
3
4
5
6
LOAD CURRENT (mA)
SUPPLY VOLTAGE (V)
MAX861 SUPPLY CURRENT
vs. SUPPLY VOLTAGE
MAX860-07
MAX860 OUTPUT CURRENT vs. CAPACITANCE
HIGH-FREQUENCY MODE
MAX860-08
MAX860 OUTPUT CURRENT vs. CAPACITANCE
MEDIUM-FREQUENCY MODE
70
OUTPUT CURRENT (mA)
60
50
40
30
V
IN
= +4.5V, V
OUT
= -4V
20
10
0
V
IN
= +3V, V
OUT
= -2.7V
f
OSC
= 50kHz
FC = GND
LV = GND
INVERTER MODE
V
IN
= +4.5V, V
OUT
= -3.5V
V
IN
= +3V, V
OUT
= -2.4V
MAX860-09
500
FC = V
DD
400
SUPPLY CURRENT (µA)
DOUBLER, LV = OUT
70
60
OUTPUT CURRENT (mA)
50
40
30
20
10
0
300
INVERTER, LV = GND
200
f
OSC
= 130kHz
FC = OUT
LV = GND
INVERTER MODE
V
IN
= +4.5V, V
OUT
= -3.5V
V
IN
= +4.5V, V
OUT
= -4V
80
V
IN
= +3V, V
OUT
= -2.4V
100
V
IN
= +3V, V
OUT
= -2.7V
0
0
1
2
3
4
5
6
SUPPLY VOLTAGE (V)
0.33
1
2.2
4.7
10
22
0.33
1
2.2
4.7
10
22
CAPACITANCE (µF)
CAPACITANCE (µF)
4
_______________________________________________________________________________________
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
