Unless otherwise specified, V

ply over the entire operating junction temperature range, 0˚C to +125˚C. Specifications appearing in plain type are measured

using low duty cycle pulse testing with T

cal analysis.

Symbol

Parameter

Conditions

Min

Typ

Max

Units

SYSTEM

Oscillator

F

osc

Oscillator Frequency

F

265

300

335

kHz

F

174

200

226

kHz

Don_max

Maximum On-Duty Cycle

V

HDRV1 and HDRV2

96

98

%

T

on_min

Minimum On-Time

150

ns

Error Amplifier

I

Feedback Input Bias

Current

V

90

250

nA

I

I

comp2_SC

COMP Output Source

Current

V

V

27

104

µA

I

I

comp2_SK

COMP Output Sink

Current

V

V

27

99

µA

Voltage References and Linear Voltage Regulators

UVLO

VLIN5 Under-voltage

Lockout Threshold

(Rising)

SS1, SS2 transition from low to high

3.6

4.0

4.4

V

R_EXT

EXT pin ON-Resistance

V

3

Ω

EXT_TH

VLIN5-to-EXT Switch

Over Threshold

Rising edge of V

EXT

4.7

V

V

OUT3

3.3V Linear Regulator

Output Voltage

≤ VIN ≤

30V, V

3.306

3.3

3.564

V

I

OUT3

3.3V Linear regulator

Current limit threshold

ON1 = HIGH, EXT = 5V

100

mA

I

LDODRV

LDODRV pin Sink

Current

V

4.0

6mA

V

LDOFB

LDODRV Feedback

Voltage

3.5V

≤ V

1.215

1.240

1.265

V

Accuracy with Load

3.5V

≤ LDO power supply voltage ≤

15V, I

1.236

V

I

LDOFB

LDOFB Leakage Current

(Sourcing)

V

50

100

nA

V

2NDFB

Secondary winding

voltage feedback detect

threshold

Falling Edge

1.3

1.5

1.7

V

Logic Inputs

V

IH

Minimum High Level

Input Voltage (SD,

FPWM/2NDFB, ON1,

ON2, F

2.0

V

V

IL

Maximum Low Level

Input Voltage for

FPWM/2NDFB, ON1

ON2, F

0.8

V

SD

0.6

V

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