AL8807 HIGH EFFICIENCY LOW 36V 1A BUCK LED DRIVER. Pin Assignments. Description. Features. Applications. Typical Application Circuit.

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1 AL887 Description The AL887 is a step-down DC/DC converter designed to drive LEDs with a constant current. The device can drive up to 9 LEDs, depending on the forward voltage of the LEDs, in series from a voltage source of 6V to 36V. Series connection of the LEDs provides identical LED currents resulting in uniform brightness and eliminating the need for ballast resistors. The AL887 switches at frequency up to 1MHz with controlled rise and fall times to reduce EMI. This allows the use of small size external components, hence minimizing the PCB area needed. Maximum output current of AL887 is set via an external resistor connected between the V IN and SET input pins. Dimming is achieved by applying either a DC voltage or a PWM signal at the CTRL input pin. An input voltage of.4v or lower at CTRL switches off the output MOSFET simplifying PWM dimming. Features LED driving current up to 1.3A (MSOP-8EP) Better than 5% accuracy High efficiency up to 96% Optimally controlled switching speeds Operating input voltage from 6V to 36V PWM/DC input for dimming control Built-in output open-circuit protection SOT5: Available in Green Molding Compound (No Br, Sb) with lead Free Finish/ RoHS Compliant (Note 1) MSOP-8EP Available in Green Molding Compound (No Br, Sb) with lead Free Finish/ RoHS Compliant (Note 1) Pin Assignments (Top View) Applications SW GND CTRL SET GND GND CTRL MR16 lamps General illumination lamps 1V powered LED Lamps 4V powered LED Lamps SOT5 (Top View) MSOP-8EP V IN SET V IN N/C SW SW Notes: 1. EU Directive /95/EC (RoHS) & 11/65/EU (RoHS ). All applicable RoHS exemptions applied.please visit our website at Typical Application Circuit D1 DFLS1 D3 DFLS 1 P1 P D4 DFLS1 C5 1nF D5 D C 15µF C3 15µF C1 1 nf V IN R1 R15 U1 SET CTRL SW GND L1 33µH C4 1µF ANODE CATHODE DFLS1 DFLS 1 AL887 GND AL887 1 of 1 February 1

2 AL887 Pin Descriptions Pin Name Pin Number SOT5 MSOP-8EP Descriptions SW 1 5, 6 Switch Pin. Connect inductor/freewheeling diode here, minimizing track length at this pin to reduce EMI. GND, 3 GND Pin Dimming and On/Off Control Input. Leave floating for normal operation. (V CTRL = V REF =.5V giving nominal average output current I OUTnom =.1/R S ) Drive to voltage below.4v to turn off output current CTRL 3 4 Drive with DC voltage (.5V < V CTRL <.5V) to adjust output current from % to 1% of I OUTnom A PWM signal (low level.4v and high level >.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. SET 4 1 Set Nominal Output Current Pin. Configure the output current of the device. V IN 5 8 Input Supply Pin. Must be locally decoupled to GND with >.µf X7R ceramic capacitor see applications section for more information. EP - EP Exposed pad/tab connect to GND and thermal mass for enhanced thermal impedance. Should not be used as electrical ground conduction path. N/C - 7 no connection Absolute Maximum Ratings Symbol Parameter Ratings Unit ESD HBM Human Body Model ESD Protection.5 kv ESD MM Machine Model ESD Protection V V IN Continuous V IN pin voltage relative to GND -.3~4 V V SW SW voltage relative to GND -.3~4 V V CTRL CTRL pin input voltage -.3 ~ 6 V I SW-RMS DC or RMS Switch current SOT5 1.5 MSOP-8EP 1.6 A I SW-PK Peak Switch current (<1%).5 A T J Junction Temperature 15 C T LEAD Lead Temperature Soldering 3 C T ST Storage Temperature Range -65 to +15 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 Symbol Parameter Min Max Unit V IN Operating Input Voltage relative to GND V V CTRLH Voltage High for PWM dimming relative to GND V V CTRLDC Voltage range for % to 1% DC dimming relative to GND.5.5 V V CTRLL Voltage Low for PWM dimming relative to GND.4 V f SW Maximum switching frequency 1 MHz I SW Continuous switch current SOT5 1 MSOP-8EP 1.3 A T J Junction Temperature Range C AL887 of 1 February 1

3 AL887 Electrical Characteristics V IN =1V, T A =5 o C, unless otherwise specified. Symbol Parameter Conditions Min Typ. Max Unit V INSU Internal regulator start up threshold V IN rising 5.9 V V INSH Internal regulator hysteresis threshold V IN falling 1 3 mv I Q Quiescent current Output not switching (Note ) 35 µa I S Input supply Current CTRL pin floating f = 5kHz ma V TH Set current Threshold Voltage mv V TH-H Set threshold hysteresis ± mv I SET SET pin input current V SET = V IN µa R CTRL CTRL pin input resistance Referred to internal reference 5 kω V REF Internal Reference Voltage.5 V R DS(on) On Resistance of SW MOSFET I SW = 1A.5.4 Ω t R SW rise time V SENSE = 1±mV f SW = 5kHz 1 ns t F SW fall time V SW =.1V~1V~.1V C L = 15pF ns I SW_Leakage Switch leakage current V IN =3V.5 μa Thermal Resistance Junction-to- SOT5 (Note 4) 5 θ JA Ambient (Note 3) MSOP-8EP (Note 5) 69 Thermal Resistance Junction-to- Ψ JL SOT5 (Note 4) 5 Lead (Note 6) C/W θ JC Thermal Resistance Junction-tocase (Note 7) MSOP-8EP (Note 5) 4.3 Notes:. AL887 does not have a low power standby mode but current consumption is reduced when output switch is inhibited: V SENSE = V. Parameter is tested with V CTRL.5V 3. Refer to figure 35 for the device derating curve. 4. Test condition for SOT5: Device mounted on FR-4 PCB (5mm x 5mm 1oz copper, minimum recommended pad layout on top layer and thermal vias to bottom layer ground plane. For better thermal performance, larger copper pad for heat-sink is needed. 5. Test condition for MSOP-8EP: Device mounted on FR-4 PCB (51mm x 51mm oz copper, minimum recommended pad layout on top layer and thermal vias to bottom layer with maximum area ground plane. For better thermal performance, larger copper pad for heat-sink is needed 6. Dominant conduction path via Gnd pin (pin ). 7. Dominant conduction path via exposed pad. AL887 3 of 1 February 1

4 AL887 Typical Performance Characteristics ( unless otherwise stated) L = 33µH V IN = 1V 1 LED R SET = 15mΩ I IN (µa) V CTRL = V V SET = VIN V IN (V) Figure 1. Supply Current (not switching) vs. Input Voltage FREQUENCY (khz) L = 68µH L = 1µH VCTRL Figure. Switching Frequency vs. VCTRL LED CURRENT (A) I CTRL (µa) V SET = V IN = 1V CTRL PIN VOLTAGE (V) V CTRL (V) Figure 3. LED Current vs. V CTRL Figure 4. I CTRL vs. VCTRL V SET = V IN = 1V.51 V CTRL (V) V CTRL (V).5.5 V SET = VIN V IN (V) Figure 5. V CTRL vs. Input Voltage (CTRL Pin Open Circuit) AMBIENT TEMPERATURE ( C) Figure 6. V CTRL VS. TEMPERATURE AL887 4 of 1 February 1

5 AL887 HIGH EFFICIENCY LOW 36V 1A BUCK LED DRIVER Typical Performancee Characteristics (cont.) (T A = 5 C unless otherwise stated) LED CURRENT ERROR (%) L = 68H, R S = 15m T A = 5C, V IN = 1V CTRL = PWM, f PWM = 5Hz 1 LED LED Current Error LED Current LED CURRENT (A) R DS(ON) (m Ω ) V SET = V IN PWM DUTY CYCLE Figure 7. I LED vs. PWM Duty Cycle V IN (V) Figure 8. SW RDS(ON N) vs. Input Voltage 36 R DS(ON) (m Ω ) V SET = V IN = 1V Ambient Temperaturee (C) Figure 9. SW R DS(ON) vs. Temperature DUTY CYCLE (%) LEDS 6 L = 68µH R S = 1m Ω 3 LEDS Figure 1. Duty Cycle vs. Input Voltage Figure. 11 SW Output Rise Time Figure. 1 SW Outpu Fall Time AL887 5 of 1 February 1 Diodes Incorporated

6 AL887 Typical Performance Characteristics (67mA LED current) () LED CURRENT ERROR (%) Figure 13. LED Current Deviation vs. Input Voltage SWITCHING FREQUENCY (khz) Figure 14. Switching Frequency vs. Input Voltage LED CURRENT ERROR (%) Figure 15. LED Current Deviation vs. Input Voltage SWITCHING FREQUENCY (khz) Figure 16. Switching Frequency vs. Input Voltage LED CURRENT ERROR (%) L = 33µH R S = 15mΩ LEDs 3 LEDs 4 LEDs 5 LEDs 6 LEDs 7 LEDs 8 LEDs 1 LED Figure 17. LED Current Deviation vs. Input Voltage SWITCHING FREQUENCY (khz) LED L = 33µH R S = 15mΩ 7 LEDs 8 LEDs 5 LEDs 1 3 LEDs 6 LEDs LEDs 4 LEDs Figure 18. Switching Frequency vs. Input Voltage AL887 6 of 1 February 1

7 AL887 Typical Performance Characteristics (1A LED current MSOP-8EP) () LED CURRENT ERROR (%) Figure 19. LED Current Deviation vs. Input Voltage SWITCHING FREQUENCY (khz) L = 1µH R S = 1mΩ 1 LED 7 LEDs 4 LEDs 5 LEDs 6 LEDs 8 LEDs LEDs 3 LEDs Figure. Switching Frequency vs. Input Voltage LED CURRENT ERROR (%) LED CURRENT ERROR (%) Figure 1. LED Current Deviation vs. Input Voltage Figure 3. LED Current Deviation vs. Input Voltage SWITCHING FREQUENCY (khz) SWITCHING FREQUENCY (khz) Figure. Switching Frequency vs. Input Voltage Figure 4. Switching Frequency vs. Input Voltage AL887 7 of 1 February 1

8 AL887 Typical Performance Characteristics (1.3A LED current MSOP-8EP) () LED CURRENT ERROR (%) Figure 5. LED Current Deviation vs. Input Voltage SWITCHING FREQUENCY (khz) L = 1µH R S = 77mΩ 1 LED LEDs 3 LEDs 5 LEDs6 LEDs 7 LEDs 8 LEDs 4 LEDs Figure 6. Switching Frequency vs. Input Voltage LED CURRENT ERROR (%) Figure 7. LED Current Deviation vs. Input Voltage SWITCHING FREQUENCY (khz) LED 5 L = 68µH R S = 77mΩ LEDs3 LEDs 4 LEDs 5 LEDs 6 LEDs7 LEDs 8 LEDs Figure 8. Switching Frequency vs. Input Voltage LED CURRENT ERROR (%) Figure 9. LED Current Deviation vs. Input Voltage SWITCHING FREQUENCY (khz) LED 1 L = 33µH R S = 77mΩ 5 LEDs 7 LEDs 6 LEDs 8 LEDs LEDs 3 LEDs 4 LEDs Figure 3. Switching Frequency vs. Input Voltage AL887 8 of 1 February 1

9 AL887 HIGH EFFICIENCY LOW 36V 1A BUCK LED DRIVER Application Information The AL887 is a hysteretic (also known as equal ripple) LED driver with integrated power switch. It is available in two packages that provide a PCB area-power dissipation capability compromise. It is recommended that at higher LED currents/smaller PCBs that the MSOP-8EP version is used to maximize the allowable LED current over a wider ambient temperature range. AL887 Operation In normal operation, when voltage is applied at +V IN, the AL887 internal switch is turned on. Current starts to flow through sense resistorr R 1, inductor L1, and the LEDs. The current ramps up linearly, and the ramp rate is determined by the input voltage +Vin and the inductor L1. This rising current produces a voltage ramp across R 1. The internal circuit of the AL887 senses the voltage across R 1 and applies a proportional voltage to the input of the internal comparator. When this voltage reaches an internally set upper threshold, the internal switch is turned off. The inductor current continues to flow through R 1, L1, the LEDs and the schottky diode D1, and back to the supply rail, but it decays, with the rate of decay determined by the forward voltage drop of the LEDs and the schottky diode. This decaying current produces a falling voltage at R 1, which is sensed by the AL887. A voltage proportional to the sense voltage acrosss R 1 is applied at the input of the internal comparator. When this voltage falls to the internally set lower threshold, the internal switch is turned on again. This switch-on-and-off cycle continues to provide the average LED current set by the sense resistor R 1. LED Current Control The LED current is controlled by the resistor R1 in Figure 3. Connected between V IN and SET the nominal average output current in the LED(s) is defined as: V I LED = THD R1 For example for a desired LED current of 66mA and a default voltage V CTRL =.5V the resulting resistor is: R1= VTHD.1 = 15 mω ILED.66 DC Dimming Further control of the LED current can be achieved by driving the CTRL pin with an external voltage (between.4v and.5v); the average LED current becomes: VCTRL VTHD I LED = V R REF SET Fig. 3 Typical Application Circuit With.5V V CTRL.5V the LED current varies linearly with V CTRL, as in figure. If the CTRL pin is brought higher than V.5V, the LED current will be clamped to approximately 1% and follows I LED = THD. R SET When the CTRL voltage falls below the threshold,.4v, the output switch is turned off which allows PWM dimming. AL887 9 of 1 February 1 Diodes Incorporated

10 AL887 Applications Information (cont.) PWM Dimming LED current can be adjusted digitally, by applying a low frequency Pulse Width Modulated (PWM) logic signal to the CTRL pin to turn the device on and off. This will produce an average output current proportional to the duty cycle of the control signal. In particular, a PWM signal with a max resolution of 1bit can be applied to the CTRL pin to change the output current to a value below the nominal average value set by resistor R SET. To achieve this resolution the PWM frequency has to be lower than 5Hz, however higher dimming frequencies can be used, at the expense of dimming dynamic range and accuracy. Typically, for a PWM frequency of 5Hz the accuracy is better than 1% for PWM ranging from 1% to 1%. 7 6 LED CURRENT (ma) Zooming in at duty cycles below 1% shows: PWM DIMMING (%) Fig. 31 PWM 5Hz 4.5 DEVIATION FROM IDEAL LOAD CURRENT (%) V IN = 1VDC L = 68µH R S =.15Ω LEDs Hz PWM DUTY CYCLE (%) Fig. 3 Low Duty Cycle PWM 3Hz The accuracy of the low duty cycle dimming is affected by both the PWM frequency and also the switching frequency of the AL887. For best accuracy/resolution the switching frequency should be increased while the PWM frequency should be reduced. The CTRL pin is designed to be driven by both 3.3V and 5V logic levels directly from a logic output with either an open drain output or push pull output stage. AL887 1 of 1 February 1

11 AL887 Applications Information (cont.) Soft Start The AL887 does not have in-built soft-start action this provides very fast turn off of the output the stage improving PWM dimming accuracy; nonetheless, adding an external capacitor from the CTRL pin to ground will provide a soft-start delay. This is achieved by increasing the time taken for the CTRL voltage to rise to the turn-on threshold and by slowing down the rate of rise of the control voltage at the input of the comparator. Adding a capacitor increases the time taken for the output to reach 9% of its final value, this delay is.1ms/nf, but will impact on the PWM dimming accuracy depending on the delay introduced. Fig. 33 Soft start with nf capacitor on CTRL pin (V IN = 3V, I LED = 667mA, 1 LED) Reducing Output Ripple Peak to peak ripple current in the LED(s) can be reduced, if required, by shunting a capacitor C across the LED(s) as shown already in the circuit schematic. A value of 1μF will reduce the supply ripple current by a factor three (approx.). Proportionally lower ripple can be achieved with higher capacitor values. Note that the capacitor will not affect operating frequency or efficiency, but it will increase start-up delay, by reducing the rate of rise of LED voltage. By adding this capacitor the current waveform through the LED(s) changes from a triangular ramp to a more sinusoidal version without altering the mean current value. Capacitor Selection The small size of ceramic capacitors makes them ideal for AL887 applications. X5R and X7R types are recommended because they retain their capacitance over wider voltage and temperature ranges than other types such as Z5U. A.μF input capacitor is sufficient for most intended applications of AL887; however a 4.7μF input capacitor is suggested for input voltages approaching 36V. AL of 1 February 1

12 AL887 HIGH EFFICIENCY LOW 36V 1A BUCK LED DRIVER Applications Information (cont.) Diode Selection For maximum efficiency and performance, the rectifier (D1) should be a fast low capacitance Schottky diode with low reverse leakage at the maximum operating voltage and temperature. The Schottky diode also provides better efficiency than silicon PN diodes, due to a combination of lower forward voltage and reduced recovery time. It is important to select parts with a peak current rating above the peak coil current and a continuous current rating higher than the maximum output load current. In particular, it is recommended to have a diode voltage rating at least 15% higher than the operating voltage to ensure safe operation during the switching and a current rating at least 1% higher than the average diode current. The power rating is verified by calculating the power loss through the diode. Schottky diodes, e.g. B4 or B14, with their low forward voltage drop and fast reverse recovery, are the ideal choice for AL887 applications. Inductor Selection Recommendedd inductor values for the AL887 are in the range 33μH to 1μH. Higher values of inductance are recommended at higher supply voltages in order to minimize errors due to switching delays, which result in increased ripple and lower efficiency. Higher values of inductance also result in a smaller change in output current over the supply voltage range. (Seee graphs). Fig. 34 Inductor value with input voltage and number of LEDs The inductor should be mounted as close to the device as possible with low resistance/stray inductance connections to the SW pin. The chosen coil should have a saturation current higher than the peak output current and a continuous current rating above the required mean output current. Suitable coils for use with the AL887 are listed in the table below: Part No. MSS MSS NPIS64D33MTRF 33 L (µ H) DCR (V) I SAT (A) Manufacturer CoilCraft NIC The inductor value should be chosen to maintain operating duty cycle and switch 'on'/'off' times over the supply voltage and load current range. AL887 1 of 1 February 1 Diodes Incorporated

13 AL887 Applications Information (cont.) The following equations can be used as a guide, with reference to Figure 1 - Operating waveforms. Switch On time Switch Off time t ON = V IN V LED I LΔI x R AVG ( + + ) S r L R SW t OFF = V LED + V D LΔI + I AVG ( + ) Where: L is the coil inductance (H) r L is the coil resistance (Ω)R S is the current sense resistance (Ω) I avg is the required LED current (A) ΔI is the coil peak-peak ripple current (A) {Internally set to.3 x Iavg} V IN is the supply voltage (V) V LED is the total LED forward voltage (V) R SW is the switch resistance (Ω) {=.5Ω nominal} V D is the diode forward voltage at the required load current (V) Thermal Considerations For continuous conduction mode of operation, the absolute maximum junction temperature must not be exceeded. The maximum power dissipation depends on several factors: the thermal resistance of the IC package θ JA, PCB layout, airflow surrounding the IC, and difference between junction and ambient temperature. The maximum power dissipation can be calculated using the following formula: P D(MAX) = (T J(MAX) T A ) / θ JA where T J(MAX) is the maximum operating junction temperature, T A is the ambient temperature, and θ JA is the junction to ambient thermal resistance. The recommended maximum operating junction temperature, T J, is 15 C and so maximum ambient temperature is determined by the AL887 s junction to ambient thermal resistance, θ JA and device power dissipation. θ JA, is layout dependent and package dependent; the AL887W5 s θ JA on a 5x5mm single layer PCB with 1oz copper standing in still air is approximately 5 C/W (16 C/W on a four-layer PCB). The maximum power dissipation at can be calculated by the following formulas: P D(MAX) = (15 C 5 C) / (5 C/W) =.4W for single-layer PCB P D(MAX) = (15 C 5 C) / (16 C/W) =.65W for standard four-layer PCB Figure 35, shows the power derating of the AL887W5 on two (one single-layer and four-layer) different 5x5mm PCB with 1oz copper standing in still air and the AL887MP on an FR4 51x51mm PCB with oz copper standing in still air. 16 x R S r L 14 MSOP-8EP POWER DISSIPATION (mw) SOT5_4 Layer SOT5_1 Layer AL AMBIENT TEMPERATURE ( C) Fig. 35 Derating Curve for Different PCB 13 of 1 February 1

14 AL887 HIGH EFFICIENCY LOW 36V 1A BUCK LED DRIVER Applications Information (cont.) EMI and Layout Considerations The AL887 is a switching regulator with fast edges and measures small differential voltages; as a result of this care has to be taken with decoupling and layout of the PCB.To help with these effects the AL887 has been developed to minimise radiated emissions by controlling the switching speeds of the internal power MOSFET. The rise and fall times are controlled to get the right compromise between power dissipation due to switching lossess and radiated EMI. The turn-on edge (falling edge) dominates the radiated EMI which is due to an interaction between the Schottky diode (D1), Switching MOSFET and PCB tracks. After the Schottky diode reverse recovery time of around 5ns has occurred; the falling edge of the SW pin sees a resonant loop between the Schottky diode capacitance and the track inductance, L TRA CK, See figure 36. Fig. 36 PCB Loop Resonance The tracks from the SW pin to the Anode of the Schottky diode, D1, and then from D1 s cathode to the decoupling capacitors C1 should be as short as possible. There is an inductance internally in the AL887 this can be assumed to be around 1nH. For PCB tracks a figure of.5nh per mm can be used to estimate the primary resonant frequency. If the track is capable of handling 1A ncreasing the thickness will have a minor effect on the inductance and length will dominate the size of the inductance. The resonant frequency of any oscillation is determined by the combined inductance in the track and the effective capacitance of the Schottky diode. An example of good layout is shown in figure 37 - the stray track inductance should be less than 5nH. VIN SET SW GND CTRL AL887 Place D1 anode, SW pin and Inductor as close as possible to minimize ringing Fig. 37 Recommended PCB Layout 14 of 1 February 1 Diodes Incorporated

15 AL887 Applications Information (cont.) Recommendations for minimising radiated EMI and other transients and thermal considerations are: 1. The decoupling capacitor (C1) has to be placed as close as possible to the V IN pin and D1 Cathode. The freewheeling diode s (D1) anode, the SW pin and the inductor have to be placed as close as possible to each other to avoid ringing. 3. The Ground return path from C1 must be a low impedance path with the ground plane as large as possible 4. The LED current sense resistor (R1) has to be placed as close as possible to the V IN and SET pins. 5. The majority of the conducted heat from the AL887 is through the GND pin. A maximum earth plane with thermal vias into a second earth plane will minimise self-heating 6. To reduce emissions via long leads on the supply input and LEDs low RF impedance capacitors (C and C5) should be used at the point the wires are joined to the PCB A Typical application for the AL887 is an LED MR16 lamp (schematic shown in Figure 38). Fig. 38 MR16 Circuit Schematic An evaluation board for the AL887 (named the AL887EV) for MR16 is available on request from your local Diodes sales representative. This board follows Diodes recommendations for low EMI. Images of the top layer and bottom layers are shown in Figure 39. Fig. 39 Recommended MR16 PCB Layout AL of 1 February 1

16 AL887 Applications Information (cont.) The associated EMI measurements for this board using the AL887 is shown in figure 4. Fig 4. AL887EV Radiated EMI Performance The EMI performance was measured at 1V DC driving two white LEDs (V F = 3.1V at 66mA) on the AL887EV. The red bold line is for EN55 class B used for domestic equipment including lighting. The bottom magenta line is the noise floor of the test chamber. The middle purple line is the EMI emitted radiation of the AL887 over 3MHz to 1MHz. This shows that the AL887 passes the standard with at least 16dB margin. MR16 lamps typically operate from 1V DC or 1V AC, using conventional electromagnetic transformers or electronic transformers. In enclosed lamps such MR16 the ability for the device to operate at high ambient temperatures is critical and figure 41 shows the surface temperature of the AL887 on AL887EV in operation under the same conditions as the EMI tests at an free air temperature of 5ºC. It is anticipated that the internal junction temperature is approximately 6 ºC hotter than the surface temperature. Fig 41. Thermal picture of AL887EV at 1V DC white LEDS at 66mA The thermal image shows that components increasing the board temperature are the inductor, Schottky diodes and the AL887. AL of 1 February 1

17 AL887 Applications Information (cont.) An inductor choice of 33µH with saturation current higher than 1.1A, will limit the frequency variation between 18kHz and 4kHz over the whole input voltage variation (8V to 18V), and therefore represent the best choice for an MR16 solution also taking into account the size constraint of the lamp. The AL887 guarantees high performance levels with both 1V AC and 1V DC power supplies. The efficiency is generally higher than 81% and current regulation is better than.1ma/v in for a DC input voltage in the range from 8V to 18V. AL of 1 February 1

18 AL887 Ordering Information AL887 XX - XX Package W5 : SOT5 MP : MSOP-8EP Packing 7 : 7 Tape & Reel 13 : 13 Tape & Reel Device Status Package Code Packaging (Note 8) Quantity 7 Tape and Reel Part Number Suffix AL887W5-7 New Product W5 SOT5 3/Tape & Reel -7 AL887MP-13 New Product MP MSOP-8EP 5/Tape & Reel -13 Notes: 8. Pad layout as shown on Diodes Inc. suggested pad layout document AP1, which can be found on our website at: Marking Information (1) SOT5 5 (Top View) 47 XX Y W X 1 3 XX : Identification code Y : Year ~9 W : Week : A~Z : 1~6 week; a~z : 7~5 week; z represents 5 and 53 week X : A~Z : Internal code Part Number Package Identification Code AL887W5-7 SOT5 B6 () MSOP-8EP Logo Part Number Y W X E AL a~z : Lead Free A~Z: Green MSOP-8EP Y : Year : - 9 W : Week : A~Z : 1 ~ 6 week; a~z : 7~5 week z represents 5 and 53 week Part Number AL887MP-13 Package MSOP-8EP AL of 1 February 1

19 AL887 Package Outline Dimensions (All Dimensions in mm) (1) Package Type: SOT5 A K J H D B C N L M SOT5 Dim Min Max Typ A B C D.95 H J K L M N α 8 All Dimensions in mm () MSOP-8EP A e D D b E1 E A A1 See Detail C D1 E c Gauge plane a L Detail C MSOP-8EP Dim Min Typ Max A A A b c D D E E E e L a 8 4 All Dimensions in mm AL of 1 February 1

20 AL887 Suggested Pad Layout 1) Package Type: SOT5 C C Z G Y C1 Dimensions Value (in mm) Z 3. G 1.6 X.55 Y.8 C1.4 C.95 X ) MSOP-8EP X Y1 C X1 C1 Dimensions Value (in mm) C1 4. C.65 X.3 X Y.8 Y Y AL887 of 1 February 1

21 AL887 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 UNDER 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 Incorporated convey any license under its patent or trademark rights, nor the rights of others. Any Customer 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 the companies whose products are represented on Diodes Incorporated website, harmless against all damages. Diodes Incorporated does not warrant or accept any liability whatsoever in respect of any products purchased through unauthorized sales channel. Should Customers purchase or use Diodes Incorporated products for any unintended or unauthorized application, Customers shall indemnify and hold Diodes Incorporated and its representatives harmless against all claims, damages, expenses, and attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized application. Products described herein may be covered by one or more United States, international or foreign patents pending. Product names and markings noted herein may also be covered by one or more United States, international or foreign trademarks. LIFE SUPPORT Diodes Incorporated products are specifically not authorized for use as critical components in life support devices or systems without the express written approval of the Chief Executive Officer of Diodes Incorporated. As used herein: A. Life support devices or systems are devices or systems which: 1. are intended to implant into the body, or. support or sustain life and whose failure to perform when properly used in accordance with instructions for use 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 perform can be reasonably expected to cause the failure of the life 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 devices or systems, and acknowledge and agree that they are solely responsible 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 systemsrelated information or 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 Diodes Incorporated products in such safety-critical, life support devices or systems. Copyright 1, Diodes Incorporated AL887 1 of 1 February 1