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Rainbow Electronics MAX844 User Manual

Page 2

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MAX840/MAX843/MAX844

Low-Noise, Regulated, -2V GaAsFET Bias

2

_______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(Figures 2a and 2c, 2.5V

V

IN

10V, V

OUT

= -2V, GND = 0V, R

L

=

, SHDN = V

IN

, T

A

= T

MIN

to T

MAX

, unless otherwise noted.

Typical values are measured at V

IN

= 3.6V and T

A

= +25°C.)

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.

Note 1:

The output may be shorted to NEGOUT or GND if the package power dissipation is not exceeded. Typical short-circuit
current from 4V to GND is 40mA.

Supply Voltage, V

IN

to GND ..................................-0.3V to 10.5V

V

NEGOUT

to GND ...................................................-10.5V to 0.3V

V

IN

to V

NEGOUT

.........................................................-0.3V to 21V

V

OUT

to GND (Note 1).......................................V

NEGOUT

to 0.3V

V

SHDN

to GND ............................................-0.3V to (V

IN

+ 0.3V)

Continuous Power Dissipation (T

A

= +70°C)

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

Operating Temperature Ranges

MAX84_I_ _A ...................................................-25°C to +85°C
MAX84_E_ _A ..................................................-40°C to +85°C

Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10sec) .............................+300°C

C4 = 10µF

V

IN

= 3.6V,

R

L

=

or 500

MAX844, V

IN

3.6V, SHDN = 0V

MAX844, V

IN

= 10V, SHDN = 0V

MAX840/MAX843, V

IN

= 10V, SHDN = 0V

MAX843/MAX844, V

CONT

= 0V

MAX843/MAX844,
V

CTRL

= 2V

MAX840, V

FB

= 0V

MAX840, V

FB

= -0.5V

MAX840, no load

CONDITIONS

mVp-p

1

V

OUT

Ripple

mV/mA

2

8

V

OUT

Load Regulation

3

8

µA

175

300

I

SHUT

Shutdown Supply Current

940

1

nA

±1

±100

I

CONT

CONT Leakage Current

nA

±1

±100

I

FB

FB Leakage Current

V

-0.516 -0.5

-0.484

V

FB

FB Voltage

-2.1

-2.0

-1.9

V

2.5

10

V

IN

Supply Voltage Range

-0.5 to

(V

IN

- 0.6)

V

OUT

Output Voltage Adjust Range

V

-2.05

-2.0

-1.95

V

OUT

Output Voltage

-2.1

-2.0

-1.9

-2.05

-2.0

-1.95

UNITS

MIN

TYP

MAX

SYMBOL

PARAMETER

80

100

120

Oscillator Frequency

F

OSC

V

IN

= 3.6V,

T

A

= +25°C

14

20

26

kHz

Input High Voltage

V

IH

SHDN

2.2

V

V

IN

2.7V,

I

OUT

= 0mA to 4mA

V

IN

2.5V,

I

OUT

= 0mA to 3mA

V

IN

2.5V,

I

OUT

= 0mA to 3mA

V

IN

2.7V,

I

OUT

= 0mA to 4mA

V

MAX840, V

FB

= 0V

MAX843/MAX844,
V

CTRL

= 2V

Input Low Voltage

V

IL

SHDN

0.35

V

Input Current

I

IN

SHDN

-1

1

µA

Input Capacitance

C

IN

SHDN

10

pF

MAX840/MAX843/
MAX844

MAX844, SHDN = 0V

No load, V

IN

3.6V

I

Q

Supply Current

µA

750

1300