40V, Ultra-Low Quiescent-Current

Linear Regulators in 6-Pin TDFN/8-Pin SO

10

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Applications Information

Output Voltage Setting

The MAX15006C/MAX15007C provide an adjustable

output voltage from 1.8V to 10V and do not operate in a

preset output voltage mode. Connect an external resis-

tive divider from OUT to FB to GND as shown in Figure

as follows:

required in the external divider for stability.

Available Output Current Calculation

The MAX15006/MAX15007 provide up to 50mA of contin-

uous output current. The input voltage range extends to

40V. Package power dissipation limits the amount of out-

put current available for a given input/output voltage and

ambient temperature. Figure 5 shows the maximum

allowable power dissipation for these devices to keep the

junction temperature below +150°C. Figure 5 assumes

that the exposed metal pad of the MAX15006/MAX15007

Use Figure 5 to determine the allowable package dissi-

pation for a given ambient temperature. Alternately, use

the following formulas to calculate the allowable pack-

age dissipation. For the TDFN package:

For the SO-EP package:

After determining the allowable package dissipation,

calculate the maximum allowable output current, with-

out exceeding the +150°C junction temperature, using

the following formula:

The above equations do not include the negligible

power dissipation from self-heating due to the IC

ground current.

Example 1 (TDFN Package):

Calculate the maximum allowable package dissipation

at the given temperature as follows:

And establish the maximum output current:

I

595.8mW

26V

3.3V

26.2mA

−

=

P

1.9048W

0.0238

W

C

125 C

70 C

5

°

°−

°

I

P

VV

50mA

OUT(MAX)

D

IN

OUT

=

−

≤

.

..

=

≤+

°

−

1 8605

70

1 8605

0 0233

Wfor T

C

W

A

W

W

C

xT

C for

C

T

C

AA

°

°

°

⎧

⎨

⎪

– 70

70

125

⎩⎩⎪

⎫

⎬

⎪

⎭⎪

.

..

=

≤+

°

−

1 9048

70

1 9048

0 0238

Wfor T

C

W

A

W

W

C

xT

C for

C

T

C

AA

°

°

°

⎧

⎨

⎪

– 70

70

125

⎩⎩⎪

⎫

⎬

⎪

⎭⎪

VV

1

R1

R2

OUT

FB

=×

+

⎛

⎝⎜

⎞

⎠⎟

TEMPERATURE (

°C)

140

120

100

40

60

80

20

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

0

0

1.9408W

(6-PIN TDFN)

1.8605W

(8-PIN SO-EP)

DERATE

23.8mW/

°C

DERATE

23.3mW/

°C

Figure 5. Calculated Maximum Power Dissipation vs. Ambient

Temperature

R1

2.2

μF

0.1

μF

OFF

ON

+1.8V TO +10V

+4V TO +40V

R2

IN

EN

GND

OUT

FB

MAX15007C

Figure 4. Setting the Adjustable Output Voltage