RT8482
7
DS8482-02 May 2012 www.richtek.com
©
Copyright 2012 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation.
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. If connected with a 20kΩ serial resistor, ACTL and DCTL can go up to 36V.
Note 3. θ
JA
is measured at T
A
= 25°C on a high effective thermal conductivity four-layer test board per JEDEC 51-7. θ
JC
is
measured at the exposed pad of the package.
Note 4. Devices are ESD sensitive. Handling precaution is recommended.
Note 5. The device is not guaranteed to function outside its operating conditions.
Note 6. When the natural maximum duty cycle of 350kHz switching frequency is reached, the switching cycle will be skipped (not
reset) as the operating condition requires to effectively stretch and achieve higher on cycle than the natural maximum
duty cycle set by the 350kHz switching frequency.
Parameter Symbol Test Conditions Min Typ Max Unit
LED Current Off Threshold at
ACTL
V
ACTL_OFF
-- 0.3 -- V
DCTL Input Current I
DCTL
0.3V ≤ V
DCTL
≤ 6V -- -- 0.5 μA
PWM Control
Switching Frequency f
SW
280 350 420 kHz
Minimum Off Time (Note 6) -- 250 -- ns
Switch Gate Driver
GBIAS Voltage V
GBIAS
I
GBIAS
= 20mA -- 8.5 -- V
I
Gate
= −50mA -- 7.2 --
Gate Voltage High V
Gate_H
I
Gate
= −100μA -- 7.8 --
V
I
Gate
= 50mA -- 0.25 --
Gate Voltage Low V
Gate_L
I
Gate
= 100μA -- 0.1 --
V
GATE Drive Rise and Fall Time 1nF Load at GATE -- 15 -- ns
PWM Switch Current Limit
Threshold
I
SW_LIM
-- 110 -- mV
OVP and Soft-Start
OVP Threshold V
OVP_th
-- 1.18 -- V
OVP Input Current I
OVP
0.7V ≤ V
OVP
≤ 1.5V -- -- 0.1 μA
Soft-Start Pin Current I
SS
V
SS
≤ 2V -- 6 -- μA
Thermal Protection
Thermal Shutdown Temperature T
SD
-- 145 -- °C
Thermal Shutdown Recovery ΔT
SD
-- 10 -- °C
