Diodes AL8805 - Manual (Page 2)

AL8805
Document number: DS35030 Rev. 4 - 2
2 of 16
www.diodes.com
July 2012
© Diodes Incorporated
AL8805
Pin Descriptions
Pin Number Pin Name Function
1 SW Switch Pin. Connect inductor/freewheeling diode here, minimizing track length at this pin to reduce EMI.
2 GND GND Pin
3 CTRL
Dimming and On/Off Control Input.
•
Leave floating for normal operation.
(V
CTRL
= V
REF
= 2.5V giving nominal average output current I
OUTnom
= 0.1/R
S
)
•
Drive to voltage below 0.4V to turn off output current
•
Drive with DC voltage (0.5V < V
CTRL
< 2.5V) to adjust output current from 20% to 100% of I
OUTnom
• A PWM signal (low level ≤ 0.4V and high level > 2.6; transition times less than 1us) allows the output
current to be adjusted below the level set by the resistor connected to SET input pin.
4 SET Set Nominal Output Current Pin. Configure the output current of the device.
5 V
IN
Input Supply Pin. Must be locally decoupled to GND with > 2.2µF X7R ceramic capacitor – see applications
section for more information.
Absolute Maximum Ratings
(@T
A
= +25°C, unless otherwise specified.)
Symbol Parameter Ratings Unit
ESD HBM Human Body Model ESD Protection 2.5 kV
ESD MM Machine Model ESD Protection 200 V
V
IN
Continuous V
IN
Pin Voltage Relative to GND -0.3 to 40 V
V
SET
SET Pin Voltage Relative to V
IN
Pin -5 to +0.3 V
V
SW
SW Voltage Relative to GND -0.3 to 40 V
V
CTRL
CTRL Pin Input Voltage -0.3 to 6 V
I
SW-DC
DC or RMS Switch current 1.25 A
I
SW-PK
Peak Switch Current (<10%) 2.5 A
T
J
Junction Temperature 150 °C
T
LEAD
Lead Temperature Soldering 300 °C
T
ST
Storage Temperature Range -65 to +150 °C
Caution: Stresses greater than the 'Absolute Maximum Ratings' specified above, may cause permanent damage to the device. These are stress ratings only;
functional operation of the device at these or any other conditions exceeding those indicated in this specification is not implied. Device reliability may be
affected by exposure to absolute maximum rating conditions for extended periods of time.
Semiconductor devices are ESD sensitive and may be damaged by exposure to ESD events. Suitable ESD precautions should be taken when handling and
transporting these devices
Recommended Operating Conditions
(@T
A
= +25°C, unless otherwise specified.)
Symbol Parameter Min Max Unit
V
IN
Operating Input Voltage relative to GND 6.0 36 V
V
CTRLH
Voltage High for PWM Dimming Relative to GND 2.6 5.5 V
V
CTRLDC
Voltage Range for 20% to 100% DC Dimming Relative to GND 0.5 2.5 V
V
CTRLL
Voltage Low for PWM Dimming Relative to GND 0 0.4 V
I
SW
Continuous Switch Current — 1 A
T
J
Junction Temperature Range -40 125 °C