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Parameter Conditions Min. Typ. Max. Units Input Voltage Range 7.0 24 30.0 VDC Max Input Voltage 0.5 Sec. Max 40.0 VDC Input Filter Internal Capacitor Output Parameter Conditions Min. Typ. Max. Units Output Voltage Range V IN = 30V 2 28 VDC Output Current See Model Selection Guide Output Current Accuracy See Model Selection Guide Output Power See Model Selection Guide Effi ciency See Model Selection Guide Capacitive Load 47 µF Operating Frequency 40 380 kHz Ripple & Noise (20 MHz) See Model Selection Guide Temperature Coeffi cient ±0.03 ±0.08 %/ ºC Thermal Impedance Natural Convection +50 ºC/W Output Short Circuit Regulated At Rated Output Current Environmental Parameter Conditions Min. Typ. Max. Units Operating Temperature Range Ambient -40 +25 +85 ºCCase +105 Storage Temperature Range -40 +125 ºC Cooling Free Air Convection Humidity RH, Non-condensing 95 % Lead Temperature (Solder) 1.5 mm From Case For 10 Sec 260 ºC Remote On/Off Control Parameter Conditions Min. Typ. Max. Units DC/DC On Open or 0.3V < VADJ <1.25V DC/DC Off VADJ <0.15V Remote Pin Drive Current V ADJ = 1.25V 1 mA Quiescent Input Current (Shutdown Mode) VIN = 30V 25 µA PWM Dimming Parameter Conditions Min. Typ. Max. Units Operation Frequency Recommended Maximum 1.0 kHz Switch On Time 200 nS Switch Off Time 200 nS Output Current Adjustment 0.0 100 % Analog Dimming Parameter Conditions Min. Typ. Max. Units Input Voltage Range At V ADJ Input 0.0 1.25 VDC Output Current Adjustment 25 100 % Control Voltage Range Limits On 0.30 1.25 VDCOff 0.0 0.15 Drive Current VADJ = 1.25V 1.0 mA EMC Compliance EMI/RFI Radiated/Conducted EN 55015 (CISPR22) Electrostatic Discharge (ESD) Class A IEC/EN 61000-4-2, -6, -8 RF Field Susceptibility Class A IEC/EN 61000-4-3 Electrical Fast Transients/Bursts On Mains Class A IEC/EN 61000-4-4 EMS Immunity EN61547 Reliability Specifi cations Parameter Conditions Min. Typ. Max. Units MTBF MIL HDBK 217F , 25 ºC, Gnd Benign 1.6 MHours MicroPower Direct

292 Page Street

Stoughton, MA 02072 USA T: (781) 344-8226 F: (781) 344-8481 E: sales@micropowerdirect.com W: www.micropowerdirect.com www.micropowerdirect.com Electrical Specifi cations Specifi cations typical @ +25°C, nominal input voltage & rated output current, unless otherwise noted. Specifi cations subject to change without notice. LD24-xx-xxx Models Available with Wire Leads (IP67 Rated) Compact, Wide Input Constant Current DC/DC LED Drivers Key Features:

  • Constant Current Output
  • Wide 7V to 30V Input Range
  • Effi ciency to 95%
  • Miniature MiniDIP Case
  • 150 mA to 1A Output
  • Meets EN 60950
  • 1.6 MHrs MTBF
  • Digital & Analog Dimming!

292 Page Street Ste D Stoughton, MA 02072 • TEL: (781) 344-8226 • FAX: (781) 344-8481 • E-Mail: sales@micropowerdirect.com www.micropowerdirect.com Typical Connection: DC/DC Input Model Number Input Output Maximum Power (W) Ripple & Noise (mV P-P, Max) Effi ciency (%, Max) PackageVoltage (VDC) Voltage (VDC) Current Range Range Max (mA) Accuracy (%) LD24-07-250 7.0 - 30.0 2.0 - 28.0 250 ±8 7 200 95 14 -Pin DIP LD24-08-300 7.0 - 30.0 2.0 - 28.0 300 ±6 8 200 95 14 -Pin DIP LD24-08-350 7.0 - 30.0 2.0 - 28.0 350 ±5 8 200 95 14 -Pin DIP LD24-14-500 7.0 - 30.0 2.0 - 28.0 500 ±6 14 250 95 16 -Pin DIP LD24-17-600 7.0 - 30.0 2.0 - 28.0 600 ±7 17 250 95 16 -Pin DIP LD24-20-700 7.0 - 30.0 2.0 - 28.0 700 ±7 20 250 95 16 -Pin DIP LD24-24-1000 7.0 - 30.0 2.0 - 28.0 1,000 ±7 24 300 95 16 -Pin DIP Notes: 1. A reversed power source could damage the unit. 4. The VADJ input should be left open if not used. Grounding VADJ will shut the unit down. Connecting VADJ to VIN may damage the unit.2. No connection should be made between input ground and the output. 3. These are step-down devices, the maximum output open voltage is equal to the input voltage. 5. Exceeding the specifi ed maximum output power could cause damage to the unit. Typical Connection: AC/DC Input Connection Notes: To comply with EN61000-4-5, a TVS should be installed before the input fi lter components. A 3.0SMCJ24A or SMCJ24A is recommended. The TVS max clamping voltage (@max peak pulse current V C) must be /H11017/H1100640V . Exceeding the maximum input rating could damage the driver. The fi lter shown (C1, C2 and L1) will help to meet conducted emission requirements. With the addition of the fi lter, the unit should meet the levels of EN 55015. Connection Notes: This is a distributed (or two-stage) AC connection. In this confi guration, the AC line in (90 to 264 VAC) is connected to the MPM-30D-15IS, a compact 30W AC/DC power supply. The MPM-30D-15IS is connected across its ± 15 VDC outputs to provide a tightly regulated 30 VDC output at 1A. The 30 VDC output powers the LED driver. The two stage approach can simplify the safety approval process (most AC/DC power supplies on the market are approved to EN 60950) and may increase design fl ex- ibility. Besides the output power, other specifi cations to consider when selecting the input AC/DC supply would include input range, safety approvals, PFC rating (which may be needed for various system energy ratings) and operating temperature range. Note: The output current adjustment circuit shown in both connection diagrams is discussed on page 4.

MicroPower Direct • 292 Page Street Ste D Stoughton, MA 02072 • TEL: (781) 344-8226 • FAX: (781) 344-8481 • E-Mail: sales@micropowerdirect.com www.micropowerdirect.com PWM Output Current Control An LED operates at its maximum effi ciency when operated at the rated drive current specifi ed by the manufacturer. Operating an LED at lower than its rated forward current not only decreases the system effi ciency; but may cause color (or wave- length) shifting. In illumination applications, this could cause visible changes to lighting. A preferred method is using pulse width modula- tion (PWM). As shown at left, the output current is adjusted by applying a PWM signal to the V ADJ input. By varying the signal duty cycle the average output current is adjusted up or down. To avoid visible fl icker, the PWM signal should be greater than 100 Hz. For duty cycles (DPWM) between 0 and 1, the output current is derived by the formula: II X DNOM MAX PWM= The VADJ input may be driven via an open collec- tor transistor (as shown). The diode and resistor suppress high amplitude negative spikes that may be caused by the drain-source capacitance of the transistor. Negative spikes on the control input of the unit could cause errors in output current or erratic operation. The V ADJ input can also be driven by the open drain output of a microcontroller. Again, any high amplitude negative spikes that may be caused by the drain- source capacitance of the FET must be supressed. PWM Control Signals PWM Dimming Application Get a full explanation of this circuit in “Driving LEDs”. Available free at the MPD website A simple method of achieving digital (or PWM) dimming is by using a 555 timer to apply a series of pulses to the VADJ input, as illustrated above. Again, we are powering the LED driver with the MPM-30D-15IS AC power supply. The 555 operates over a supply voltage range of 4.5 VDC to 18VDC. Here it is connected to the 15 VDC output of the SR7805 switching regulator (also driven by the MPM-20S-24EPB). Care should be taken to minimize ripple at the V CC input. Excess ripple could cause timing errors. The timer is connected for astable (free run) operation. The frequency is set by R1, R2 and C6. The timing capacitor (C6) charges through R1 and D2. When it reaches the level of 2/3 VCC, the discharge pin (pin 7) goes low and C6 will discharge through D1 and R2 to the internal discharge transistor. When the C6 voltage drops to 1/3 VCC, the discharge pin goes high and C6 begins to charge again. The formulas for calculating the frequency and duty cycle are included in the MPD application note “Driving LEDs”. The diodes (D1 and D2) allow duty cycles below 50% to be set. Diode D1 bypasses R2 while C6 is charging. Diode D2 is optional (but recommended), essentially block- ing R2 during the charge period. Theoretically, this circuit will allow for duty cycles over a range of about 5% to 95%. If manual adjustment is desired, a potentiometer may be substituted for R2 (with some adjustment of the circuit). The size of C6 is generally not critical, but it should be as low leakage as pos- sible. In order to avoid excessive current fl ow through the internal discharge transistor, it is recommended that R 1 be at least 5 k/H9024.

We Power Your Success - For Less! 292 Page Street Ste D Stoughton, MA 02072 • TEL: (781) 344-8226 • FAX: (781) 344-8481 • E-Mail: sales@micropowerdirect.com www.micropowerdirect.com Notes:

  • All dimensions are typical in inches (mm)
  • Tolerance x.xx = ±0.02 (±0.50)
  • Pin 1 is marked by a “dot” or indentation on the top of the unit Mechanical Dimensions - 16 Pin DIP Analog Output Current Control Analog Output Current Control (7 - 30 VDC IN) Mechanical Dimensions - 14 Pin DIP Pin Connections - 16 Pin DIP Pin Function 1- V IN -DC Supply 9 +LED LED Anode Conn. 2- V IN -DC Supply 10 +LED LED Anode Conn. 3V ADJ PWM, On/Off 15 +V IN +DC Supply 7 -LED LED Cathode Conn. 16 +V IN +DC Supply 8 -LED LED Cathode Conn. Pin Connections - 14 Pin DIP Pin Function 1- V IN -DC Supply 8 +LED LED Anode Conn. 2V ADJ PWM, On/Off 14 +V IN +DC Supply 7 -LED LED Cathode Conn. In the second circuit, the input DC/DC has been changed to the F2506RU. The 4:1 input of the converter allows for wider input bus levels (in this case 24 VDC). The POL regulator is also replaced by the shunt regulator (D 1). The regulator, connected in parallel with the resistor network, will maintain the voltage across R 2 and R3 at 2.5 VDC, insuring that the 1.25 VDC limit on the VADJ pin will not be exceeded. When using the analog control input, the nominal output current is equal to: .II x V 12 5 NOM MAX ADJ The VADJ input should be left open if not used. Grounding VADJ will shut the unit down. Connecting VADJ to directly to +VIN may damage the unit. The output current of the unit can also be set by adjusting the voltage level on the V ADJ input to a value between 0.3V to 1.25V (I OUT will vary from 25% to 100% of rated output current). Care must be taken not to exceed 1.25V on this input, or the driver may be damaged. The simple analog circuit at left uses the F2506RW, a 30W, dual 15V output DC/DC converter. Operating from an input line of 12 VDC, the converter sets the input to the LED driver at 30 VDC. The POL regulator, driven off the same input line maintains the control voltage (for the V ADJ input) at 5 VDC. The resister network of R1 and R2 can now be used to set the output current level of the LED driver. This level is equal to: V RR R XV ADJ CTRL= +