45V, 400mA, Low-Quiescent-Current

Linear Regulator with Adjustable Reset Delay

10

______________________________________________________________________________________

Calculate package dissipation at the given temperature

as follows:

And establish the maximum current:

Example 3:

Calculate package dissipation at the given temperature

as follows:

And find the maximum output current:

In example 3 the maximum output current is calculated

as 666mA, however, the maximum output current can-

not exceed 400mA.

Use Figure 4 to quickly determine maximum allowable out-

put current for selected ambient temperatures.

Output-Capacitor Selection and

Regulator Stability

For stable operation over the full temperature range

and with load currents up to 400mA, use a 15µF (min)

output capacitor with an ESR < 0.25

Ω. To reduce noise

and improve load-transient response, stability, and

power-supply rejection use larger output capacitor val-

ues such as 22µF.

Some ceramic capacitor dielectrics exhibit large

capacitance and ESR variation with temperature. For

capacitor dielectrics such as Y5V, use 22µF or more to

ensure stability at temperatures below -10°C. With X7R

or X5R dielectrics, 15µF should be sufficient at all oper-

ating temperatures. To improve power supply rejection

and transient response, use a minimum 47µF low-ESR

capacitor from IN to GND.

I

(2.666W)

(14V) (10V)

mA

I

4 0mA

OUT(MAX)

OUT(MAX)

=

−

=⇒

=

666

0

I

(1.191W)

(14V) (5V)

mA

OUT(MAX)

.

=

−

= 92 7

P

2.666W

0.0333

W

C

(125 C

70 C)

0

W

D

.

=−

°

°− °

=

8345

Chip Information

PROCESS: BiCMOS

45

40

35

30

25

20

15

10

5

0

°C

°C

°C

0.25

0.20

0.15

0.10

0.05

0.30

0.35

0.40

0.45

0.50

0

Figure 4. Maximum Output Current vs. Input Voltage (16-Pin

TQFN)