BD6590MUV
Technical Note
●Output voltage ripple for PWM dimming
Conditions: 8serial 6parallel, LED current=20mA/ch, VBAT=5V, Coil Power=7V, Ta=25℃, output capacitor =2.2μF(50V/B3)
PWMDRV
Lower ripple Voltage
(under 200mV)
Output Voltage (AC)
780mA
Input Current
1ms/div.
●LED current rise and fall for PWM dimming
Conditions: 8serial 6parallel, LED current=20mA/ch, VBAT=5V, Coil Power=7V, Ta=25℃, output capacitor=2.2μF(50V/B3)
PWMDRV
PWMDRV
Output Voltage
Output Voltage
114ns
624ns
40ns/div.
LED Current
LED Current
400ns/div.
PWMPOW (ta 25, Frequency 200Hz LED 10x6ch)
LED current vs Duty
PWMDRV(ta 25, Frequency 200Hz, LED 10x6ch)
LED current vs Duty
100
10
100
10
1
1
0.1
0.01
0.1
12V
6V
12V
6V
0.01
0.001
26V
26V
0.001
0.1
1
10
100
0.1
1
10
100
duty[%]
Duty[%]
PWM characteristics of current driver PWM
PWM characteristics of power control PWM
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2011.07 - Rev.B
13/26
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