5

RT4531

DS4531-01

July 2016

www.richtek.com

©

Copyright

2016 Richtek Technology Corporation. All rights reserved.

is a registered trademark of Richtek Technology Corporation.

Parameter

Symbol

Test Conditions

Min

Typ

Max

Unit

Maximum Duty Cycle

90

95

--

%

Back Light N-MOSFET Ron

100

270

400

m



Back Light Current Limit

After 5ms in soft-start

1.15

1.5

1.85

A

Back Light Over Voltage

Protection

35.5

36.5

37.5

V

IFBx Pin Over Voltage

Threshold

Measure on IFBx pin

--

5

--

V

Logic Control

One Wire Detection Delay

tes_delay

Measure from En low to high

300

--

--

s

One Wire Detection Time

tes_det

En pin low time in detection

window

400

--

--

s

One Wire Detection Window

tes_win

Measure from En low to high,

Fblosc = 1MHz

--

1

--

ms

Start Time of Program

Stream

3

--

--

s

End Time of Program

Stream

3

--

--

s

High Time Low Bit

Logic 0

2

--

180

s

Low Time Low Bit

Logic 0

2 x

tH_LB

--

360

s

High Time High Bit

Logic 1

2 x

tL_HB

--

360

s

Low Time High Bit

Logic 1

2

--

180

s

EN Input

Voltage

Logic-Low

--

--

0.4

V

Logic-High

1.4

--

--

PWM Input

Voltage

Logic-Low

--

--

0.4

V

Logic-High

1.4

--

--

EN Pull Low Resistor

280

400

520

k



PWM Pull Low Resistor

280

400

520

k



PWM Logic Low Width to

Shutdown

PWM pin high to low, then

shutdown

20

--

--

ms

EN Logic Low Width to

Shutdown

EN pin high to low, then

shutdown

2.5

--

--

ms

Note 1. Stresses beyond those listed

“Absolute Maximum Ratings” may cause permanent damage to the device. These are

stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in

the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions may

affect device reliability.

Note 2.

Note 3. Devices are ESD sensitive. Handling precaution is recommended.

Note 4. The device is not guaranteed to function outside its operating conditions.