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Typical operating characteristics – Rainbow Electronics MAX861 User Manual

Page 4

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MAX860/MAX861

50mA, Frequency-Selectable,
Switched-Capacitor Voltage Converters

4

_______________________________________________________________________________________

__________________________________________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.)

0.7

0

0

OUTPUT VOLTAGE DROP FROM

SUPPLY VOLTAGE vs. LOAD CURRENT

0.8

MAX860-01

LOAD CURRENT (mA)

V

OUT

DROP (V)

30

0.4

0.2

10

20

50

0.6

40

0.1

0.3

0.5

V

DD

= +1.5V

V

DD

= +2.5V

V

DD

= +3.5V

V

DD

= +4.5V, +5.0V

V

DD

= +5.5V

ALL FREQUENCIES

2

-14

1.5 2.0

3.0

4.0

OSCILLATOR FREQUENCY vs.

SUPPLY VOLTAGE

-6

0

MAX860-02

SUPPLY VOLTAGE (V)

PERCENTAGE FREQUENCY CHANGE (

%

)

(FROM FREQUENCY MEASURED WITH V

DD

= +5V)

2.5

3.5

-2

-4

4.5 5.0 5.5

-8

-10

-12

ALL FREQUENCIES,
LV CONNECTED TO GND
(INVERTER) OR OUT (DOUBLER)

1.0

20

0

0

1

3

5

OUTPUT SOURCE RESISTANCE (R

O

) vs.

SUPPLY VOLTAGE

4

16

MAX860-03

SUPPLY VOLTAGE (V)

OUTPUT SOURCE RESISTANCE (

)

2

4

12

8

2

6

10

14

18

ALL FREQUENCIES

32

0

-60

-20

40

140

OUTPUT SOURCE RESISTANCE (R

O

) vs.

TEMPERATURE

8

28

MAX860-04

TEMPERATURE (°C)

OUTPUT SOURCE RESISTANCE (

)

20

100

24

16

-40

0

60 80

120

20

12

4

V

DD

= +3V

V

DD

= +5V

V

DD

= +1.5V

ALL FREQUENCIES

0

0

MAX861 SUPPLY CURRENT

vs. SUPPLY VOLTAGE

MAX860-07

SUPPLY VOLTAGE (V)

SUPPLY CURRENT (

µ

A)

100

200

300

500

1

2

3

4

5

6

400

DOUBLER, LV = OUT

INVERTER, LV = GND

FC = V

DD

100

0

0.01

1

100

MAX860

EFFICIENCY vs. LOAD CURRENT

20

MAX860-05

LOAD CURRENT (mA)

EFFICIENCY (%)

40

60

80

10

30

50

70

90

0.1

10

INVERTER

FC = V

DD

V

DD

= +1.5V

V

DD

= +3V

V

DD

= +5V

0

0

MAX860 SUPPLY CURRENT

vs. SUPPLY VOLTAGE

MAX860-06

SUPPLY VOLTAGE (V)

SUPPLY CURRENT (

µ

A)

100

200

300

500

1

2

3

4

5

6

400

DOUBLER, LV = OUT

INVERTER, LV = GND
(V

DD

> 3V)

FC = V

DD

70

0

0.33

MAX860 OUTPUT CURRENT vs. CAPACITANCE

HIGH-FREQUENCY MODE

MAX860-08

CAPACITANCE (

µ

F)

OUTPUT CURRENT (mA)

4.7

40

20

1

2.2

22

60

10

10

30

50

V

IN

= +4.5V, V

OUT

= -3.5V

V

IN

= +4.5V, V

OUT

= -4V

V

IN

= +3V, V

OUT

= -2.4V

V

IN

= +3V, V

OUT

= -2.7V

f

OSC

= 130kHz

FC = OUT
LV = GND
INVERTER MODE

80

70

0

0.33

MAX860 OUTPUT CURRENT vs. CAPACITANCE

MEDIUM-FREQUENCY MODE

MAX860-09

CAPACITANCE (

µ

F)

OUTPUT CURRENT (mA)

4.7

40

20

1

2.2

22

60

10

10

30

50

V

IN

= +4.5V, V

OUT

= -3.5V

V

IN

= +3V, V

OUT

= -2.4V

V

IN

= +4.5V, V

OUT

= -4V

V

IN

= +3V, V

OUT

= -2.7V

f

OSC

= 50kHz

FC = GND
LV = GND
INVERTER MODE