apply over the full Operating Junction Temperature Range. Unless otherwise specified: V

Ω. (Note

3) (Continued)

Symbol

Parameter

Conditions

Min

Typ

Max

Unit

PWM COMPARATOR

COMP to OUT delay

COMP set to 2V

CS stepped 0 to

0.4V, time to OUT

transition low, C

load

=0.

20

ns

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

4.2

5.1

6

V

COMP at Max Duty Cycle

2.75

V

COMP Short Circuit Current

COMP = 0V

0.6

1.1

1.5

mA

SLOPE COMPENSATION

Slope Comp Amplitude

(LM5021-1 only)

CS pin to PWM

Comparator offset at

maximum duty cycle

70

90

110

mV

OUTPUT SECTION

OUT High Saturation

IOUT = 50mA, VCC

- OUT

0.6

1.1

V

OUT Low Saturation

IOUT = 100mA

0.3

1

V

Peak Source Current

OUT = VCC/2.

0.3

A

Peak Sink Current

OUT = VCC/2.

0.7

A

Rise time

C

25

ns

Fall time

C

10

ns

HICCUP MODE

V

OVLD

Over load detection threshold

COMP pin

V

V

V

V

V

HIC

Hiccup mode threshold

SS pin

V

V

V

V

V

RST

Hiccup mode Restart threshold

SS pin

0.1

0.3

0.5

V

I

DTCS

Dead-time current source

0.1

0.25

0.4

µA

I

OVCS

Overload detection timer current

source

6

10

14

µA

THERMAL RESISTANCE

θ

JA

MSOP-8 Junction to Ambient

0 LFM

200

˚C/W

θ

JA

MDIP-8 Junction to Ambient

0 LFM

107

˚C/W

Note 1: Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Ratings are conditions under which operation of the device

is intended to be functional. For guaranteed specifications and test conditions, see the Electrical Characteristics.

Note 2: The human body model is a 100 pF capacitor discharged through a 1.5k

Ω resistor into each pin.

Note 3: Min and Max limits are 100% production tested at 25˚C. Limits over the operating temperature range are guaranteed through correlation using Statistical

Quality Control (SQC) methods. Limits are used to calculate National’s Average Outgoing Quality Level (AOQL).

Note 4: Device thermal limitations may limit usable range.

Note 5: After initial turn-on at VIN = 20V.

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