2024年9月17日发(作者：奕洋)

CMOS Monolithic Voltage Converter

M

A

X

6

6

0

______________Detailed Description

The MAX660 capacitive charge-pump circuit either

inverts or doubles the input voltage (see Typical

Operating Circuits). For highest performance, low

effective series resistance (ESR) capacitors should be

used. See Capacitor Selectionsection for more details.

When using the inverting mode with a supply voltage

less than 3V, LV must be connected to GND. This

bypasses the internal regulator circuitry and provides

best performance in low-voltage applications. When

using the inverter mode with a supply voltage above

3V, LV may be connected to GND or left open. The part

is typically operated with LV grounded, but since LV

may be left open, the substitution of the MAX660 for the

ICL7660 is simplified. LV must be grounded when over-

driving OSC (see Changing Oscillator Frequencysec-

tion). Connect LV to OUT (for any supply voltage) when

using the doubling mode.

one-half of the charge-pump cycle. This introduces a

peak-to-peak ripple of:

V

RIPPLE

= I

OUT

+I

OUT

(ESR

C2

)

2(f

PUMP

) (C2)

For a nominal f

PUMP

of 5kHz (one-half the nominal

10kHz oscillator frequency) and C2 = 150µF with an

ESR of 0.2Ω, ripple is approximately 90mV with a

100mA load current. If C2 is raised to 390µF, the ripple

drops to 45mV.

Positive Voltage Doubler

The MAX660 operates in the voltage-doubling mode as

shown in the Typical Operating no-load

output is 2 x V

IN

.

Other Switched-Capacitor Converters

Please refer to Table 1, which shows Maxim’s charge-

pump offerings.

__________Applications Information

Negative Voltage Converter

The most common application of the MAX660 is as a

charge-pump voltage inverter. The operating circuit

uses only two external capacitors, C1 and C2 (see

Typical Operating Circuits).

Even though its output is not actively regulated, the

MAX660 is very insensitive to load current changes. A

typical output source resistance of 6.5Ωmeans that

with an input of +5V the output voltage is -5V under

light load, and decreases only to -4.35V with a load of

100mA. Output source resistance vs. temperature and

supply voltage are shown in the Typical Operating

Characteristicsgraphs.

Output ripple voltage is calculated by noting the output

current supplied is solely from capacitor C2 during

Changing Oscillator Frequency

Four modes control the MAX660’s clock frequency, as

listed below:

FC

Open

FC = V+

Open or

FC = V+

Open

OSC

Open

Open

External

Capacitor

External

Clock

Oscillator Frequency

10kHz

80kHz

See Typical Operating

Characteristics

External Clock Frequency

When FC and OSC are unconnected (open), the oscil-

lator runs at 10kHz typically. When FC is connected to

V+, the charge and discharge current at OSC changes

from 1.0µA to 8.0µA, thus increasing the oscillator

Table 1. Single-Output Charge Pumps

MAX828

Package

Op. Current

(typ, mA)

Output Ω

(typ)

Pump Rate

(kHz)

Input (V)

SOT 23-5

0.06

20

12

1.25 to 5.5

MAX829

SOT 23-5

0.15

20

35

1.25 to 5.5

MAX860

SO-8,

µMAX

MAX861

SO-8,

µMAX

MAX660

SO-8

MAX1044

SO-8,

µMAX

0.03

6.5

5

1.5 to 10

ICL7662

SO-8

0.25

125

10

1.5 to 10

ICL7660

SO-8,

µMAX

0.08

55

10

1.5 to 10

0.2 at 6kHz,0.3 at 13kHz,0.12 at 5kHz,

0.6 at 50kHz,1.1 at 100kHz,1 at 40kHz

1.4 at 130kHz2.5 at 250kHz

12

6, 50, 130

1.5 to 5.5

12

13, 100, 150

1.5 to 5.5

6.5

5, 40

1.5 to 5.5

CMOS Monolithic Voltage Converter

M

A

X

6

6

0

ABSOLUTE MAXIMUM RATINGS

Operating Temperature Ranges

Supply Voltage (V+ to GND, or GND to OUT).......................+6V

MAX660C_ _........................................................0°C to +70°C

LV (OUT - 0.3V) to (V+ + 0.3V)

MAX660E_ _.....................................................-40°C to +85°C

FC and OSC The least negative of

.-55°C to +125°C

(OUT - 0.3V) or (V+ - 6V) to (V+ + 0.3V)

Storage -65°to +160°C

OUT and V+ Continuous 120mA

Lead Temperature (soldering, 10sec)...........................+300°C

Output Short-Circuit Duration to GND (Note 1)....................1sec

Continuous Power Dissipation (T

A

= +70°C)

Plastic DIP (derate 9.09mW/°C above + 70°C)............727mW

SO (derate 5.88mW/°C above +70°C)..........................471mW

CERDIP (derate 8.00mW/°C above +70°C)..................640mW

Note 1:OUT may be shorted to GND for 1sec without damage, but shorting OUT to V+ may damage the device and should be

avoided. Also, for temperatures above +85°C, OUT must not be shorted to GND or V+, even instantaneously, or device

damage may result.

Stresses beyond those listed under “Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional

operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to

absolute maximum rating conditions for extended periods may affect device reliability.

ELECTRICAL CHARACTERISTICS

(V+ = 5V, C1 = C2 = 150µF, test circuit of Figure 1, FC = open, T

A

= T

MIN

to T

MAX

, unless otherwise noted.) (Note 2)

PARAMETER

Operating Supply Voltage

R

L

= 1kΩ

CONDITIONS

Inverter, LV = open

Inverter, LV = GND

Doubler, LV = OUT

Supply Current

Output Current

No load

FC = open, LV = open

FC = V+, LV = open

100

100

15

6.5

5

40

10

80

±1

±8

96

92

98

96

88

99.0099.96%

%

10.0

12

kHz

µA

Ω

MIN

3.0

1.5

2.5

0.12

1

TYPMAX

5.5

5.5

5.5

0.5

3

mA

mA

V

UNITS

T

A

≤+85°C, OUT more negative than -4V

T

A

> +85°C, OUT more negative than -3.8V

T

A

≤+85°C, C1 = C2 = 10µF, FC = V+ (Note 4)

I

L

= 100mA

FC = open

FC = V+

FC = open

FC = V+

R

L

= 1kΩconnected between V+ and OUT

R

L

= 500Ωconnected between OUT and GND

I

L

= 100mA to GND

T

A

≤+85°C, C1 = C2 = 150µF

T

A

≤+85°C

Output Resistance (Note 3)

Oscillator Frequency

OSC Input Current

Power Efficiency

Voltage-Conversion

Efficiency

No load

Note 2:In the test circuit, capacitors C1 and C2 are 150µF, 0.2Ωmaximum ESR, aluminum electrolytics.

Capacitors with higher ESR may reduce output voltage and efficiency. See Capacitor Selectionsection.

Note 3:Specified output resistance is a combination of internal switch resistance and capacitor ESR. See Capacitor Selection section.

Note 4:The ESR of C1 = C2 ≤0.5Ω. Guaranteed by correlation, not production tested.

2024年9月17日发(作者：奕洋)

CMOS Monolithic Voltage Converter

M

A

X

6

6

0

______________Detailed Description

The MAX660 capacitive charge-pump circuit either

inverts or doubles the input voltage (see Typical

Operating Circuits). For highest performance, low

effective series resistance (ESR) capacitors should be

used. See Capacitor Selectionsection for more details.

When using the inverting mode with a supply voltage

less than 3V, LV must be connected to GND. This

bypasses the internal regulator circuitry and provides

best performance in low-voltage applications. When

using the inverter mode with a supply voltage above

3V, LV may be connected to GND or left open. The part

is typically operated with LV grounded, but since LV

may be left open, the substitution of the MAX660 for the

ICL7660 is simplified. LV must be grounded when over-

driving OSC (see Changing Oscillator Frequencysec-

tion). Connect LV to OUT (for any supply voltage) when

using the doubling mode.

one-half of the charge-pump cycle. This introduces a

peak-to-peak ripple of:

V

RIPPLE

= I

OUT

+I

OUT

(ESR

C2

)

2(f

PUMP

) (C2)

For a nominal f

PUMP

of 5kHz (one-half the nominal

10kHz oscillator frequency) and C2 = 150µF with an

ESR of 0.2Ω, ripple is approximately 90mV with a

100mA load current. If C2 is raised to 390µF, the ripple

drops to 45mV.

Positive Voltage Doubler

The MAX660 operates in the voltage-doubling mode as

shown in the Typical Operating no-load

output is 2 x V

IN

.

Other Switched-Capacitor Converters

Please refer to Table 1, which shows Maxim’s charge-

pump offerings.

__________Applications Information

Negative Voltage Converter

The most common application of the MAX660 is as a

charge-pump voltage inverter. The operating circuit

uses only two external capacitors, C1 and C2 (see

Typical Operating Circuits).

Even though its output is not actively regulated, the

MAX660 is very insensitive to load current changes. A

typical output source resistance of 6.5Ωmeans that

with an input of +5V the output voltage is -5V under

light load, and decreases only to -4.35V with a load of

100mA. Output source resistance vs. temperature and

supply voltage are shown in the Typical Operating

Characteristicsgraphs.

Output ripple voltage is calculated by noting the output

current supplied is solely from capacitor C2 during

Changing Oscillator Frequency

Four modes control the MAX660’s clock frequency, as

listed below:

FC

Open

FC = V+

Open or

FC = V+

Open

OSC

Open

Open

External

Capacitor

External

Clock

Oscillator Frequency

10kHz

80kHz

See Typical Operating

Characteristics

External Clock Frequency

When FC and OSC are unconnected (open), the oscil-

lator runs at 10kHz typically. When FC is connected to

V+, the charge and discharge current at OSC changes

from 1.0µA to 8.0µA, thus increasing the oscillator

Table 1. Single-Output Charge Pumps

MAX828

Package

Op. Current

(typ, mA)

Output Ω

(typ)

Pump Rate

(kHz)

Input (V)

SOT 23-5

0.06

20

12

1.25 to 5.5

MAX829

SOT 23-5

0.15

20

35

1.25 to 5.5

MAX860

SO-8,

µMAX

MAX861

SO-8,

µMAX

MAX660

SO-8

MAX1044

SO-8,

µMAX

0.03

6.5

5

1.5 to 10

ICL7662

SO-8

0.25

125

10

1.5 to 10

ICL7660

SO-8,

µMAX

0.08

55

10

1.5 to 10

0.2 at 6kHz,0.3 at 13kHz,0.12 at 5kHz,

0.6 at 50kHz,1.1 at 100kHz,1 at 40kHz

1.4 at 130kHz2.5 at 250kHz

12

6, 50, 130

1.5 to 5.5

12

13, 100, 150

1.5 to 5.5

6.5

5, 40

1.5 to 5.5

CMOS Monolithic Voltage Converter

M

A

X

6

6

0

ABSOLUTE MAXIMUM RATINGS

Operating Temperature Ranges

Supply Voltage (V+ to GND, or GND to OUT).......................+6V

MAX660C_ _........................................................0°C to +70°C

LV (OUT - 0.3V) to (V+ + 0.3V)

MAX660E_ _.....................................................-40°C to +85°C

FC and OSC The least negative of

.-55°C to +125°C

(OUT - 0.3V) or (V+ - 6V) to (V+ + 0.3V)

Storage -65°to +160°C

OUT and V+ Continuous 120mA

Lead Temperature (soldering, 10sec)...........................+300°C

Output Short-Circuit Duration to GND (Note 1)....................1sec

Continuous Power Dissipation (T

A

= +70°C)

Plastic DIP (derate 9.09mW/°C above + 70°C)............727mW

SO (derate 5.88mW/°C above +70°C)..........................471mW

CERDIP (derate 8.00mW/°C above +70°C)..................640mW

Note 1:OUT may be shorted to GND for 1sec without damage, but shorting OUT to V+ may damage the device and should be

avoided. Also, for temperatures above +85°C, OUT must not be shorted to GND or V+, even instantaneously, or device

damage may result.

Stresses beyond those listed under “Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional

operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to

absolute maximum rating conditions for extended periods may affect device reliability.

ELECTRICAL CHARACTERISTICS

(V+ = 5V, C1 = C2 = 150µF, test circuit of Figure 1, FC = open, T

A

= T

MIN

to T

MAX

, unless otherwise noted.) (Note 2)

PARAMETER

Operating Supply Voltage

R

L

= 1kΩ

CONDITIONS

Inverter, LV = open

Inverter, LV = GND

Doubler, LV = OUT

Supply Current

Output Current

No load

FC = open, LV = open

FC = V+, LV = open

100

100

15

6.5

5

40

10

80

±1

±8

96

92

98

96

88

99.0099.96%

%

10.0

12

kHz

µA

Ω

MIN

3.0

1.5

2.5

0.12

1

TYPMAX

5.5

5.5

5.5

0.5

3

mA

mA

V

UNITS

T

A

≤+85°C, OUT more negative than -4V

T

A

> +85°C, OUT more negative than -3.8V

T

A

≤+85°C, C1 = C2 = 10µF, FC = V+ (Note 4)

I

L

= 100mA

FC = open

FC = V+

FC = open

FC = V+

R

L

= 1kΩconnected between V+ and OUT

R

L

= 500Ωconnected between OUT and GND

I

L

= 100mA to GND

T

A

≤+85°C, C1 = C2 = 150µF

T

A

≤+85°C

Output Resistance (Note 3)

Oscillator Frequency

OSC Input Current

Power Efficiency

Voltage-Conversion

Efficiency

No load

Note 2:In the test circuit, capacitors C1 and C2 are 150µF, 0.2Ωmaximum ESR, aluminum electrolytics.

Capacitors with higher ESR may reduce output voltage and efficiency. See Capacitor Selectionsection.

Note 3:Specified output resistance is a combination of internal switch resistance and capacitor ESR. See Capacitor Selection section.

Note 4:The ESR of C1 = C2 ≤0.5Ω. Guaranteed by correlation, not production tested.