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3

SLTS165E - FEBRUARY 2002 - REVISED MARCH 2003

PT4821—48V

35-W Triple Output Isolated DC/DC

Converter for Logic Applications

PT4821 Electrical Specifications

PT4821

Characteristics

Symbols

Conditions

Min

Typ

Max

Units

Output Current

Each output

—8

(2)

0.1

(1)

—6

(2)

A

0.1

(1)

—6

(2)

A

Input Voltage Range

Continuous

36

—

75

V

Surge (1 minute)

—

—

80

Set-Point Voltage

3.24

3.3

3.36

2.45

2.5

2.55

V

1.47

1.5

1.53

Temperature Variation

–40°C

—

±0.5

—

—

±0.5

—

Line Regulation

—

±0.1

±0.5

Load Regulation

All outputs, 0

—

±0.1

±0.5

Total Output Voltage Variation

Includes set-point, line, load,

—

—

–40°C

—

—

Efficiency

η

—

87

—

%

—40

—

(0 to 20MHz bandwidth)

—35

—

—25

—

Transient Response

—

200

—

µSec

—

3

—

Output Adjust Range

—

±10

—

Over-Current Threshold

Total, all outputs. Reset with auto-recovery

—

14

—

A

Switching Frequency

350

400

450

kHz

Under Voltage Lockout

—

35.5

—

V

—

34

—

Turn-On Time

—

—ms

Enable Control (pins 1 & 2)

High-Level Input Voltage

4

—

V

Low-Level Input Voltage

–0.2

—

0.8

Low-Level Input Current

—

12mA

Standby Input Current

pins 1 & 2 open circuit

—

1

5

mA

Internal Input Capacitance

—

1.14

—

µF

External Output Capacitance

0

220

0

220

µF

0

220

Primary/Secondary Isolation

1500

—

—

V

—

2,200

—

pF

10

——M

Ω

Notes: (1) The converter will operate down to no load with reduced specifications.

(3) Limits are specified by design.

(4) Measured from the application of the input voltage to the instance that all outputs are in regulation.

input power is applied. The maximum open-circuit voltage is 4V.

(6) Ultra-low ESR capacitors, such as organic or polymer aluminum electrolytic types, may cause instability. Consult the factory before using.