al5811 ev 2 user guide 75 ma , 60v low - side adjustable linear led driver al5811 ev 2 rev 2 page 1 of 8 january 201 3 www.diodes.com general description the al581 1 is an adjustable linear led driver offering excellent temperature stability and output handling capability. the al5811 simplifies the design of linear and isolated or non - isolated led drivers by setting the led current w ith standard value resistors. the al5811 has an open drain output that can swing from 1v up to 60v enabling it drive long led chains. its low 0.5v r set pin is outside of the led current path and so accuracy is maintained while minimizing the required ove rhead to regulate the led current. this reduces its power dissipation when compared to traditional linear led drivers. this makes it ideal for driving leds up to 7 5ma. longer led chains can be driven by tapping v cc from the chain, where the chain voltage may exceed 60v. the al5811 ev2 evaluation board provides u - dfn3030 - 6 package. key features ? low reference voltage (v rset =0.5v) ? - 40 ? c to 125 ? c temperature range ? msop - 8ep and u - dfn3030 - 6 packages applications ? linear led driver ? isolated offline led converters ? led signs ? instrumentation illumination specifications parameter value input voltage 3.5v C 6 0v (low side) >60v ( floating gnd ) led current 75 ma (adjustable) xy dimension 0.62 x 0.57 rohs compliance yes top - view evm ( al5811 ev2 ) al5811 ev 2 (u - dfn3030 - 6) connection instructions input voltage : red wire ground : b lack wires led: white wire
al5811 ev 2 user guide 75 ma , 60v low - side adjustable linear led driver al5811 ev 2 rev 2 page 2 of 8 january 201 3 www.diodes.com board layout s note: b y defaul t, t his evaluation boar d provides low side current led string configuration in this user guide document . for design flexibility, multiple application circuits can be derived in both low and high side current led configurations with use of pwm dimming . evaluation boar d connecti on setup and power - up procedur e current led string procedure to evaluation board in low side current led configuration
al5811 ev 2 user guide 7 5ma , 60v low - side adjustable linear led driver al5811 ev 2 rev 2 page 3 of 8 january 201 3 www.diodes.com 1. by default, the evaluation board is preset at 75 ma as low side current led configuration. 2. ensure that the dc s ource is switched off or disconnected. 3. connect the dc line wire s of power supply to v in and gnd terminals on the b oard. 4. connect the anode wire of external led string to v in of the board. 5. connect the cathod e wire of external led string to l ed terminal of t he board. 6. load 10k? to r1 on the board. do not l oad any components on r2 and r3. 7. ensure that the area around the board is clear and safe, and preferably that the board and leds are enclosed in a transparent safety cover. 8. turn on the main switch. led strin g should light up with led. other typical circuit design options i) current led string procedure in high side current led configuration 1. the evaluation can be configured as high side current led configuration. 2. ensure that the dc s ource is switched off or disconnected. 3. connect the line wire of the dc power supply to v in and led terminals on the b oard. 4. connect the gnd wire of the dc power supply to gnd terminals o n the board. 5. connect the anode wire of external led string to floating gnd of the board. 6. connect the cathode wire of external led string to earth gnd of the dc power supply. 7. load 10k? to r1 on the board. do not load any components on r2 and r3. 8. observe max 60v differential between vin and floating gnd when applied vin > 60v . 9. in the high side circuit configuration, extreme high voltage may be present. please use caution and try not to touch any components on the board or input leads. 10. turn on the main switch. led string should light up with led.
al5811 ev 2 user guide 7 5ma , 60v low - side adjustable linear led driver al5811 ev 2 rev 2 page 4 of 8 january 201 3 www.diodes.com ii) current led string pro cedure in low side current led c onfiguration with pwm dimming 1. the evaluation board can be configured as low side current led configuration with use of pwm dimming. 2. ensure that the dc source is switched off or disconn ected. 3. connect the dc line wire s of power supply to v in and gnd terminals on the b oard. 4. connect the anode wire of external led string to v in of the board. 5. connect the cathode wire of external led string to led terminal of the board. 6. load 10k? to r2 on the board. do not load any components on r1 and r3. 7. insert external mosfet across r3 pads of the board for pwm dimming control . 8. ensure that the area around the board is clear and safe, and preferably that the board and leds are enclosed in a transparent safe ty cover. 9. turn on the main switch. led string should light up with led.
al5811 ev 2 user guide 7 5ma , 60v low - side adjustable linear led driver al5811 ev 2 rev 2 page 5 of 8 january 201 3 www.diodes.com schematic f or AL5811EV2 ( u - dfn3030 - 6 ) bill of materia ls bill of material for al5811 ev 2 u - dfn3030 - 6 evaluation board (low side current led string configuration) # name qu antity part number manufacturer description 1 u1 1 al5811ff diodes inc adjustable linear driver in u - dfn3030 - 6 2 c1 1 12101c104kat2a avx corp cap cer 0.1 f 100v 10% x7r 1210 3 r 1 1 rr1220p - 103 - d susumu res 10k ? 1/10w 0.5% 0805 smd 4 r2, r3 0 n/a n/a n /a
al5811 ev 2 user guide 75 ma , 60v low - side adjustable linear led driver al5811 ev 2 rev 2 page 6 of 8 january 201 3 www.diodes.com functional performance
al5811 ev 2 user guide 7 5ma , 60v low - side adjustable linear led driver al5811 ev 2 rev 2 page 7 of 8 january 201 3 www.diodes.com
al5811 ev 2 user guide 7 5ma , 60v low - side adjustable linear led driver al5811 ev 2 rev 2 page 8 of 8 january 201 3 www.diodes.com important notice diodes incorporated makes no warranty of any kind, express or implied, with regards to this document, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose (and their equivalents und er the laws of any jurisdiction). diodes incorporated and its subsidiaries reserve the right to make modifications, enhancements, improvements, corrections or other changes without further notice to this document and any product described herein. diodes incorporated does not assume any liability arising out of the application or use of this document or any product described herein; neither does diodes incorpo rated convey any license under its patent or trademark rights, nor the rights of others. any cus tomer or user of this document or products described herein in such applications shall assume all risks of such use and will agree to hold diodes incorporated and all t he companies whose products are represented on diodes incorporated website, harmless aga inst all damages. diodes incorporated does not warrant or accept any liability whatsoever in respect of any products purchased through unauthor ized sales channel. should customers purchase or use diodes incorporated products for any unintended or unauth orized application, customers shall indemnify and hold diodes incorporated and its representatives harmless against all claims, damages, expenses, and attorney f ees arising out of, directly or indirectly, any claim of personal injury or death associated wi th such unintended or unauthorized application. products described herein may be covered by one or more united states, international or foreign patents pending. product nam es and markings noted herein may also be covered by one or more united states, int ernational or foreign trademarks. life support diodes incorporated products are specifically not authorized for use as critical components in life support devices or system s without the express written approval of the chief executive officer of diodes in corporated. as used herein: a. life support devices or systems are devices or systems which: 1. are intended to implant into the body, or 2. support or sustain life and whose failure to perform when properly used in accordance with instructions for u se provided in the labeling can be reasonably expected to result in significant injury to the user. b. a critical component is any component in a life support device or system whose failure to perfor m can be reasonably expected to cause the failure of the l ife support device or to affect its safety or effectiveness. customers represent that they have all necessary expertise in the safety and regulatory ramifications of their life support d evices or systems, and acknowledge and agree that they are solely res ponsible for all legal, regulatory and safety - related requirements concerning their products and any use of diodes incorporated products in such safety - critical, life support devices or systems, notwithstanding any devices - or systems - related information o r support that may be provided by diodes incorporated. further, customers must fully indemnify diodes incorporated and its representatives against any damages arising out of the use of diod es incorporated products in such safety - critical, life support dev ices or systems. copyright ? 20 1 3 , diodes incorporated www.diodes.com
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