RT8474A Datasheet, PDF (9/13 Pages) Richtek Technology Corporation – High Voltage Multiple-Topology LED Driver

RT8474A
OVP Voltage vs. Temperature
1.3
VOVP
1.2
1.1
1.0
0.9
-50 -25
OVP Recovery
VCC = 24V
0
25 50 75
Temperature (°C)
100 125
Power On from VCC
Frequency vs. VCC
510
505
500
495
490
485
480
0
5 10 15 20 25 30 35 40 45 50
VCC (V)
Power Off from VCC
VIN
(20V/Div)
VOUT
(20V/Div)
IOUT
(200mA/Div)
VIN
(20V/Div)
VOUT
(20V/Div)
VIN = 24V, IOUT = 340mA, L = 47μH, LED = 6pcs
Time (25ms/Div)
IOUT
(200mA/Div)
VVIINN== 2244VV,, IIOOUUTT== 334400mmAA,, LL== 4477μμHH,, LLEEDD== 66ppccss
Time (50ms/Div)
OVP Turn On when LED Take Off and Restore
VIN
(20V/Div)
VOVP
(1V/Div)
VOUT
(20V/Div)
IOUT
(500mA/Div)
VIN = 30V, IOUT = 340mA, L = 47μH, LED = 7pcs
Time (250ms/Div)
SW
(50V/Div)
VOUT
(20V/Div)
VIN
(20V/Div)
IOUT
(200mA/Div)
Switching
VIN = 24V, IOUT = 340mA, L = 47μH, LED = 6pcs
Time (2.5μs/Div)
Copyright ©2015 Richtek Technology Corporation. All rights reserved.
DS8474A-05 April 2015
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
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