6

DS8577-00 November 2011

www.richtek.com

RT8577

Parameter

Symbol

Test Conditions

Min

Typ

Max

Unit

Dimming

Logic-High

1.2

--

--

PWM Threshold

Voltage

Logic-Low

--

--

0.35

V

PWM Boost Controller

--

1

--

MHz

Switching Frequency

--

100

--

kHz

Minimum On Time

--

100

--

ns

Maximum Duty Cycle

Dmax

80

--

--

%

SEN Current Sense Limit

Input Current Limit

--

0.5

--

V

Gate Driver Source

--

2.5

--

A

Gate Driver Sink

--

3

--

A

OVP Threshold

--

1.2

--

V

UVP Threshold

--

0.6

--

V

SCP Threshold

LED1 to LED4

--

4.3

--

V

Soft-Start Current

--

6

--

μA

Thermal Shutdown Temperature

Lockout Temperature Point

--

150

--

°C

Thermal Shutdown Hysteresis

Resume Temperature Point

--

20

--

°C

STATUS Low Voltage

Open Drain at 10mA

--

--

0.5

V

Note 1.

Stresses listed as the above “Absolute Maximum Ratings” may cause permanent damage to the device. These are for

stress ratings. 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 for extended periods may

remain possibility to affect device reliability.

Note 2.

51-7 thermal measurement standard. The measurement case position of

Note 3.

Devices are ESD sensitive. Handling precaution is recommended.

Note 4.

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