Datasheet AL8860Q (Diodes) - 2

AL8860Q Q Typical Applications Circuit
VIN (4.5V to 40V)
T C U D O R P W E Pin Descriptions N Pin Number Pin Name Function
1 SET Connect resistor RS from this pin to VIN to define nominal average output current: IOUT_NOM = 0.1/Rs 2,3 GND Ground Multi-function On/Off and brightness control pin: • Leave floating for normal operation. • Drive voltage below 0.2V to turn off output current • Drive with DC voltage (0.3V < VCTRL< 2.5V) to adjust output current from 0 to 100% of IOUT_NOM。 4 CTRL Linear adjustment range from 5% to 100% of IOUTNOM • Drive with PWM signal from open-collector or open-drain transistor to adjust output current. Linear adjustment range from 1% to 100% of IOUT_NOM for f < 500Hz • Connect a capacitor from this pin to ground to increase soft-start time. (Default soft-start time = 0.1ms. Additional soft-start time is approximately 1.5ms/1nF) 5,6 SW Drain of NDMOS switch. 7 N/C No Connection 8 VIN Input voltage (4.5V to 40V). Decouple to ground with 10μF or higher X7R ceramic capacitor close to device. Exposed pad. Connect to GND and thermal mass for enhanced thermal impedance. Should not be used as EP EP electrical ground conduction path.
Functional Block Diagram
SET SW 1 5, 6 8 VIN 4.5V
VDD Current Generator
4.5V_Drv
Monitor
Comp
BG &
Ref
Hysteresis Reference Control
PWM
Logic & Driver
4
PWM/DC
CTRL PWM
OTP
OTP
Dimming
2, 3 GND AL8860Q 2 of 15 May 2019 Document number: DS41797 Rev. 2 - 2
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