3 AMP POSITIVE STEP-DOWN

INTEGRATED SWITCHING REGULATOR

78HT300

Series

Standard Application

C1 = Optional 1µF ceramic

C2 = Required 100µF electrolytic

Pin-Out Information

Pin No. Function

2

GND

Ordering Information

78HT3

C

Output Voltage

XX

Y

05

= 5.0 Volts

53

= 5.25 Volts

Package Suffix

V

= Vertical Mount

H

= Horizontal

Mount

The 78HT300 is a series of wide

input voltage, 3 terminal Integrated

Switching Regulators (ISRs). Em-

ploying a ceramic substrate, these

ISRs have a maximum output current

of 3A. The output voltage is laser-

trimmed for high accuracy.

The 78HT300 series regulators

have internal short-circuit and over-

temperature protection and may be

used in a wide variety of applications.

Specifications

Characteristics

78HT300 SERIES

(T

Symbols

Conditions

Min

Typ

Max

Units

Output Current

0.1*

—

3.0

A

Input Voltage Range

—

28

V

Output Voltage Tolerance

—

±1.0

±2.0

%Vo

Line Regulation

—

±0.4

±0.8

Load Regulation

0.1

—

±0.2

±0.4

Ripple/Noise

—

1

—

%Vo

Transient Response

50% load change

—

100

—

µSec

(with 100µF output cap)

5.0

Efficiency

η

—

80

—

%

Switching Frequency

700

750

800

kHz

Absolute Maximum

—

-40

—

+70

°C

Operating Temperature Range

Recommended Operating

Free Air Convection, (40-60LFM)

-40

—

+70**

°C

Temperature Range

Thermal Resistance

θ

ja

Free Air Convection, (40-60LFM)

—

35

—

°C/W

Storage Temperature

—

-40

—

+125

°C

Mechanical Shock

—

Per Mil-STD-883D, Method 2002.3

—

500

—

G’s

Mechanical Vibration

—

Per Mil-STD-883D, Method 2007.2,

—10

—

G’s

20-2000 Hz, soldered in a PC board

Weight

—

—

—

11

—

Grams

* ISR will operate down to no load with reduced specifications.

** See Thermal Derating chart.

Note: The 78HT300 Series requires a 100µF electrolytic or tantalum output capacitor for proper operation in all applications.

78HT300

C2

+

Vout

GND

GND

Vin

C1

1

2

3

(For dimensions and PC board

layout see Package Style 600.)

Revised 6/30/98