LDF24E-xx-xxx SSeries Miniature, SMT Constant Current Output DC/DC LED Drivers Electrical Specifications Specifications typical @ +25°C, nominal input voltage & rated output current, unless otherwise noted. Specifications subject to change without notice. Input Parameter • 300 - 700 mA Output Current Input Voltage Range Max Input Voltage • Constant Current Output Input Filter • Miniature SMTCase Output Parameter • PWM & Analog Dimming Output Current Accuracy • Wide 5.5V to 48V Input Range Output Current Stability Output Capacitive Load • Efficiency to 96% Ripple & Noise • 2.0 MHrs MTBF Temperature Coefficient Output Short Circuit • Low, Low Cost! Environmental Parameter Key Features: Conditions Typ. 24.0 Max. 48.0 55.0 Units VDC VDC Typ. ±2.0 Max. ±3.0 ±1.0 1,000 120 ±0.015 Units % % µF mV P-P %/ºC Typ. +25 +25 Max. +85 +71 +100 +125 Units 95 260 % ºC See Note 1 Internal Capacitor Conditions Min. Vin = 24V Vin = 48V Continuous Conditions 300 mA, 350 mA Output Models All Other Models Case Operating Temperature Range, Ambient Operating Temperature Range, Case Storage Temperature Range Cooling Humidity Lead Temperature Physical Case Size Case Material Weight Remote On/Off Control Parameter DC/DC On DC/DC Off Remote Pin Drive Current Quiescent Input Current (Shutdown Mode) PWM Dimming Parameter Operation Frequency Reliability Specifications Parameter MTBF Min. -40 -40 -55 Free Air Convection RH, Non-condensing 1.5 mm From Case For 10 Sec ºC ºC ºC 0.94 x 0.54 x 0.295 Inches (23.86 x 13.70 x 7.50 mm) Non-Conductive Black Plastic (UL94-V0) 0.212 Oz (6.0g) Conditions Min. Vcont = 5.0 VDC Vin = 24V, Vcont = <0.6 VDC Conditions Conditions MIL HDBK 217F, 25ºC, Gnd Benign Typical Connection: DC Input MicroPower Direct 292 Page Street Suite D Stoughton, MA 02072 USA T: (781) 344-8226 F: (781) 344-8481 E: [email protected] W: www.micropowerdirect.com Min. 5.5 Typical Connection: AC Input Typ. Max. Units Open Or 2.8 VDC < 6.0 VDC <0.6 VDC 1 mA 400 µA Min. 0.2 Typ. Max. 10 Units kHz Min. 2.0 Typ. Max. Units MHours Connection Notes: 1. Input filter components (C1, L1 & C2) are used to help meet the conducted emissions requirements (EN 55022 B) for the unit. Recommended values are: C2 - 2.2 µF L1 - 1.25 mH C3 - 1.0 µF Other components added to the circuit include an input storage capacitor to help prevent problems due to input line sags and an output capacitor to improve performance. Recommended values are: C1 - 470 µF C4 - 1.0 µF 2 To comply with EN61000-4-5, a TVS should 2. be installed before the input filter components. A SMCG51 is recommended. www.micropowerdirect.com www.micropowerdirect.com Model Selection Guide Input Voltage (VDC) Model Number Output Voltage Current (mA) 0.0 - 300 0.0 - 350 0.0 - 500 0.0 - 600 0.0 - 700 Nominal Range (VDC) 24 24 24 24 24 5.5 - 48.0 5.5 - 48.0 5.5 - 48.0 5.5 - 48.0 5.5 - 48.0 3.3 - 36.0 3.3 - 36.0 3.3 - 36.0 3.3 - 36.0 3.3 - 36.0 LDF24E-10-300 LDF24E-12-350 LDF24E-18-500 LDF24E-21-600 LDF24E-25-700 PWM Output Current Control Dimming Control Efficiency (%, Max) PWM/Analog PWM/Analog PWM/Analog PWM/Analog PWM/Analog 96 96 96 96 96 Specification Notes: 1. Exceeding 55V on the unit input could 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. 4. When not used, the PWM/Cont input (Pin 3) or should be left open if not used. 5. Exceeding the specified maximum output power could cause damage to the unit. Typical Connection: Parallel Output Connection Notes: 1. A positive temperature coefficient PTC is connected to each parallel channel for protection. Output current may be adjusted by using a pulse width modulated (PWM) signal. By varying the signal duty cycle (as shown at right) the output current is adjusted up or down. Mechanical Dimensions Output current may be calculated by using the formula: IOUT = (DT - 0.6) T Where IOUT IRATED D T = = = = x IRATED Required output current Full rated output current for the unit Pulse width of the he control signal Cycle of the control signal The TON of the driver signal must be greater than 0.7 mS. An audible noise may be generated during the digital dimming process of the driver, since the control circuit frequency is within the is within the range of human hearing (20 Hz - 20 kHz). Analog Output Current Control Analog dimming is accomplished by using a simple resistor divider network, as illustrated above. The output current is varied by changing the voltage level present at Pin 10. The amount variation is shown in chart at right. Analog Control vs Output Notes: • All dimensions are typical in inches (mm) • Tolerance x.xx = ±0.01 (±0.25) • Pin 1 is marked by a “dot” or indentation on the top of the unit The maximum voltage level that can be applied to Pin 10 is 15V. Exceeding this may damage the driver. Solder Layout Pin Connections Analog and PWM control of the driver should not be attempted at the same time. The control pin not being used should be left open. Pin Function Pin Function 1 7 8 Gnd PWM, On/Off -VOUT 9 10 16 +VOUT Analog Dimming +VIN MicroPower Direct We Power Your Success - For Less! 292 Page Street Ste D Stoughton, MA 02072 • TEL: (781) 344-8226 • FAX: (781) 344-8481 • E-Mail: [email protected]