Micropac Industries cannot assume any responsibility for any circuits shown or represent that they are free from patent infringement.

Micropac reserves the right to make changes at any time in order to improve design and to supply the best product possible.

MICROPAC INDUSTRIES, INC. HYBRID MICROELECTRONICS PRODUCTS DIVISION

• 905 E. Walnut St., Garland, TX 75040 • (972) 272-3571 • Fax (972) 494-2281

www.micropac.com

12/13/01

3

52150/52175

POSITIVE ADJUSTABLE 5-AMP VOLTAGE REGULATOR

DESIGN CONSIDERATIONS

This device has thermal overload protection from excessive power and internal short circuit protection which limits the

circuit’s maximum current. Thus, the device is protected from overload abnormalities. Although the internal power

dissipation is limited, the junction temperature must be kept below the maximum specified temperature (150ºC). It is

recommended by the manufacturer that the maximum junction temperature be kept as low as possible for increased

reliability. To calculate the maximum junction temperature or heat sink required, the following thermal resistance

values should be used.

Package

Type

Max

TO-3

1.8

2.5

Where:

The device is designed to operate without external compensation components. However, the amount of external

filtering of these voltage regulators depends upon the circuit layout. If in a specific application the regulator is more

than four inches from the filter capacitor, a 2

µF solid tantalum capacitor should be used at the input. A 1µF capacitor

should be used at the output to reduce transients created by fast switching loads, as seen in the basic test circuit.

These filter capacitors must be located as close to the regulator as possible.

Caution: Permanent damage can result from forcing the output voltage higher than the input voltage. A protection

diode from output to input should be used if this condition exists.

VOLTAGE OUTPUT

The device has an adjustable output voltage from 5.0V to 24V which can be programmed by the external resistor

network (potentiometer or two fixed resistors) using the relationship:

Example:

If R1 = 0

Ω and R2 = 5kΩ, Then

R2

Or, if R1 = 10 k

Ω and R2 = 5 kΩ then