Electrical Characteristics (All Versions)

Symbol

Parameters

Conditions

Typical

Min

Max

Units

COMMON DEVICE PARAMETERS for all versions (Note 5)

I

S

Input Supply

(Switch Off)

11

15.5/16.5

mA

Current

(Note 8)

I

50

100/115

mA

V

UV

Input Supply

R

3.30

3.05

3.75

V

Undervoltage

Lockout

f

O

Oscillator Frequency

Measured at Switch Pin

R

100

85/75

115/125

kHz

V

f

SC

Short-Circuit

Measured at Switch Pin

Frequency

R

25

kHz

V

V

EAO

Error Amplifier

Upper Limit

2.8

2.6/2.4

V

Output Swing

(Note 7)

Lower Limit

0.25

0.40/0.55

V

(Note 8)

I

EAO

Error Amp

(Note 9)

Output Current

165

110/70

260/320

µA

(Source or Sink)

I

SS

Soft Start Current

V

11.0

8.0/7.0

17.0/19.0

µA

V

D

Maximum Duty

R

98

93/90

%

Cycle

(Note 7)

I

L

Switch Leakage

Switch Off

15

300/600

µA

Current

V

V

SUS

Switch Sustaining

dV/dT = 1.5V/ns

65

V

Voltage

V

SAT

Switch Saturation

I

0.45

0.65/0.9

V

Voltage

I

CL

NPN Switch

4.0

3.0

7.0

A

Current Limit

θ

JA

Thermal Resistance

T Package, Junction to

Ambient (Note 10)

65

θ

JA

T Package, Junction to

Ambient (Note 11)

45

θ

JC

T Package, Junction to

Case

2

θ

JA

S Package, Junction to

Ambient (Note 12)

56

˚C/W

θ

JA

S Package, Junction to

Ambient (Note 13)

35

θ

JA

S Package, Junction to

Ambient (Note 14)

26

θ

JC

S Package, Junction to

Case

2

Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating ratings indicate conditions the device is intended to

be functional, but device parameter specifications may not be guaranteed under these conditions. For guaranteed specifications and test conditions, see the Electrical

Characteristics.

Note 2: Note that switch current and output current are not identical in a step-up regulator. Output current cannot be internally limited when the LM2585 is used as

a step-up regulator. To prevent damage to the switch, the output current must be externally limited to 3A. However, output current is internally limited when the

LM2585 is used as a flyback regulator (see the Application Hints section for more information).

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