IRU1205

IRU1205-18 / IRU1205-25 / IRU1205-28

IRU1205-30 / IRU1205-33 / IRU1205-36

3

Rev. 2.3

07/16/02

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PIN #

PIN SYMBOL

PIN DESCRIPTION

The input pin of the regulator. Typically a large storage capacitor is connected from

this pin to ground to insure that the input voltage does not sag below the minimum

drop out voltage during the load transient response. This pin must always be higher

the device to regulate properly.

Ground pin. This pin must be connected to the lowest potential in the system and all

other pins must be at higher potential with respect to this pin.

Enable pin. A low signal or left open on this pin shuts down the output. This pin must

minimize the error due to the error amplifier, select the values of the resistor dividers

to be less than 10K

V.

A 470 to 1000pF bypass capacitor connected to this pin reduces the output noise.

The output of the regulator. A minimum of 2.2

mF with max ESR of 1V capacitor must

be connected from this pin to ground to insure stability.

5-PIN

Output

SOT-23

Voltage

IRU1205

1.25V

IRU1205-18

1.8V

IRU1205-25

2.5V

IRU1205-28

2.8V

IRU1205-30

3.0V

IRU1205-33

3.3V

IRU1205-36

3.6V

Note 3: Ground current is the regulator quiescent cur-

rent plus the pass transistor current. The total current

from the supply is the sum of the load current plus the

ground pin current.

Note 4: The specification applies for the junction tem-

perature of 0 to +125

8C.

Note 1: Low duty cycle pulse testing with Kelvin con-

nections is required in order to maintain accurate data.

Note 2: Dropout voltage is defined as the minimum dif-

voltage drops 1% below its nominal value.

PIN DESCRIPTIONS

The output voltage of the adjustable device can be set

using:

Where:

R1 = Resistor connected from output to the Adj pin

R2 = Resistor connected from Adj pin to Gnd

1

2

3

4

4

5

Gnd

En

Adj

(Adjustable Only)

(Fixed Only)

Table 1- Nominal output voltage vs. part number.

Vo = 1.25

3 1+

R1

R2

(

)