type apply over full Operating Junction Temperature range.V

Ω unless otherwise stated. (Note

3) (Continued)

Symbol

Parameter

Conditions

Min

Typ

Max

Units

RAMP GENERATOR

Ramp Current 1

Vin = 36V, Vout=10V

136

160

184

µA

Ramp Current 2

Vin = 10V, Vout=10V

18

25

32

µA

PWM COMPARATOR

Forced Off-time

500

ns

Min On-time

80

ns

COMP to PWM Comparator Offset

0.7

V

ERROR AMPLIFIER

Feedback Voltage

Vfb = COMP

1.207

1.225

1.243

V

FB Bias Current

10

nA

DC Gain

70

dB

COMP Sink / Source Current

3

mA

Unity Gain Bandwidth

3

MHz

THERMAL SHUTDOWN

Tsd

Thermal Shutdown Threshold

165

˚C

Thermal Shutdown Hysteresis

25

˚C

THERMAL RESISTANCE

θ

JC

Junction to Case

4

˚C/W

θ

JA

Junction to Ambient

40

˚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 100pF 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).

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