LM5020

SNVS275F – MAY 2004 – REVISED APRIL 2006

www.ti.com

Electrical Characteristics (continued)

temperature range. Unless otherwise specified: VIN = 48V, VCC = 10V, and RT = 31.6k

Ω.

(1)

Symbol

Parameter

Conditions

Min

Typ

Max

Units

CS Sink Impedance (clocked)

35

55

Ω

Soft Start

Softstart Current Source

7

10

13

µA

Softstart to COMP Offset

0.35

0.55

0.75

V

Oscillator

Frequency1 (RT = 31.6k)

175

200

225

kHz

Frequency2 (RT = 9.76k)

560

630

700

kHz

Sync threshold

2.4

3.2

3.8

V

PWM Comparator

Delay to Output

COMP set to 2V,

25

ns

CS stepped 0 to 0.4V,

Time to onset of OUT

transition low

Min Duty Cycle

COMP=0V

0

%

Max Duty Cycle (-1 Device)

75

80

85

%

Max Duty Cycle (-2 Device)

50

%

COMP to PWM Comparator Gain

0.33

COMP Open Circuit Voltage

4.3

5.2

6.1

V

COMP Short Circuit Current

COMP=0V

0.6

1.1

1.5

mA

Slope Compensation

Slope Comp Amplitude

Delta increase at PWM

80

105

130

mV

(LM5020-1 Device Only)

Comparator to CS

Output Section

Output High Saturation

0.25

0.75

V

Output Low Saturation

0.25

0.75

V

Rise Time

Cload = 1nF

18

ns

Fall Time

Cload = 1nF

15

ns

Thermal Shutdown

Tsd

Thermal Shutdown Temp.

165

°C

Thermal Shutdown Hysteresis

25

°C

(3)

Specification applies to the oscillator frequency. The operational frequency of the LM5020-2 devices is divided by two.

4

Submit Documentation Feedback

Copyright © 2004–2006, Texas Instruments Incorporated

Product Folder Links: LM5020