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IRUH3301A2AK

IRUH3301A2AP

Application Information

The ADJ Pin is connected as noted in the “General Layout Rules” section.

Over-Current & Over-Temperature Protection

The IRUH3301 series provides over-current protection by means of a timed latch function. Drive

current to the internal PNP pass transistor is limited by an internal resistor (Rb in Fig. 3) between

voltage across this resistor to exceed 0.5V (nom), the latch feature will be triggered. The time-to-

latch (t

will not be set. If the latch is set the drive current to the PNP pass transistor will be disabled. The

latch will remain set until one of the following actions occur:

1. The SHDN Pin voltage is brought above 1.2V and then lowered below 0.8V.

2. The V

If the junction temperature of the regulator IC exceeds 140°C nominal, the thermal shutdown circuit

will set the internal latch and disable the drive current to the PNP pass transistor as described

above. After the junction temperature falls below a nominal 125°C, the latch can be reset using

either of the actions described above.

Under-Voltage Lock-Out

(nominal). There is a nominal 100mV hysteresis about this point.

Input Voltage Range

reduced to avoid the activation of over current protection at 2.9V < V

recommended for performance optimization when 2.9V < V

into under-voltage lock-out when V

track V

rise rate for slow V

Setting the Output Voltage

IRUH3301Axxx

0.1uF and 1uF

Ceramic;

Two 100uF

Low ESR

Tantalum

V

IN

GND

SHDN

ADJ

V

OUT

0.1uF and 1uF

Ceramic;

Two 100uF

Low ESR

Tantalum

Input

Voltage

Output

Voltage

R1

Ω

⎟

⎠

⎞

⎜

⎝

⎛

−

=

499

*

1

800

.

0

1

V

V

R

OUT

Table 1 shows the closest nominal 0.1% tolerance R1 value to provide a given output voltage.

Table 1- Values of R1 for a Given Output Voltage

0.9

1.0

1.2

1.5

1.8

2.5

3.3

Nearest R1 Value (0.1%), (Ohms)

61.9

124

249

437

619

1060

1560