IRPLLED1A International Rectifier, IRPLLED1A Datasheet
IRPLLED1A
Specifications of IRPLLED1A
Related parts for IRPLLED1A
IRPLLED1A Summary of contents
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... Bill of Materials ………………………..……………………………….26-27 13. PCB Layout ………………………………………………………………...27 IRPLLED1A IRPLLED1A Table of Contents Page ...
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... Important Safety Information The IRPLLED1A does not provide galvanic isolation of the LED drive output from the line input. Therefore if the system is supplied directly from a non-isolated input, an electrical shock hazard exists at the LED outputs and these should not be touched during operation. Although the output voltage is low this electrical shock hazard still exists. ...
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... It is recommended that for laboratory evaluation that the IRPLLED1A board be used with an isolated DC input supply. The IRS25401/11 series Buck topology is suitable only for final applications where isolation is either not necessary or provided elsewhere in the system. 2. Constant current control The IRS25401/ time-delayed hysteretic Buck controller. During normal operating conditions the output current is regulated via the IFB pin voltage to a nominal value of 500mV ...
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HO switches high after the delay t_HO_on. The cycle then repeats continuously at a frequency depending on the load current and the values of the output inductor and capacitor. Fig. 3 IRS25401/11 Control Signals, Iavg=1.2A The switching ...
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Ω Ω Since some of these equivalent values ...
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Fig. 5 Vout = 16V 470uH, COUT = 33uF 1600 1400 1200 1000 800 600 400 200 0 10 Fig. 6 Vbus = 100V 470uH, COUT ...
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Output L1 and COUT selection In order to maintain good output current regulation with minimum ripple, the value of L1 needs to be adequately sized. COUT is optional and can also be used for energy storage, which allows the ...
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Fig. 9 Iout = 350mA, Vin = 50V, COUT = 0uF 345 343 341 339 337 335 333 331 329 327 325 13 Fig. 10 Iout = 350mA, ...
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The output capacitor can be used simultaneously to reduce the frequency and improve current control accuracy. Fig. 11 shows how the capacitance reduces the frequency over a range of input voltage. A capacitance of 4.7uF has a large effect on ...
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Fig. 13 Iout = 350mA, Vout = 16.8V 470uH The addition of the COUT is essentially increasing the amount of energy that can be stored in the output ...
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... The inductor for the IRPLLED1A evaluation board was selected to supply the maximum output current of 1.5A. Due to constraints of size a value of 470uH was chosen, which provides good performance. The IRPLLED1A may be used with or without the output capacitor COUT connected. If COUT is not connected the system runs at higher frequency and consequently with reduced efficiency due to switching losses ...
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... Fig. 16 IRPLLED1A Evaluation Board Schematic Note: Rout is needed only in few applications www.irf.com RD-0608 12 ...
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... MOSFET body diode may not be an issue. For higher frequency higher current applications a diode could provide lower power losses with respect to a MOSFET. With a low side MOSFET fitted to the IRPLLED1A evaluation board reverse recovery current peaks 8A were measured. This resulted in a temperature rise which could be reduced by replacing the low side MOSFET with an appropriate freewheeling diode ...
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Fig. 18 Using a diode on the low side, Vin = 100V, Iout = 1.5A, Vout = 17V Fig. 19 Low side FET vs. low side diode comparison, Vin = 100V, Iout = 1.5A, Vout = 17V www.irf.com RD-0608 14 ...
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... A combination of diode and MOSFET together is also a possibility if required. The IRPLLED1A board allows for an additional MOSFET switch added. In this case, during the dead time, instead of the body diode freewheeling the additional diode would be conducting ...
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The resistance between VBUS and V CC (RS1) should be large enough to minimize the current sourced directly from the input voltage line. Through this supply resistor a current will flow to charge the V CC capacitor. Once the capacitor ...
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RS2 ( ) 2 − Out max − Out 2 max Ω ≤ Ω ...
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... The following circuit is one of many low cost implementations: VBUS COM Fig. 22 Suggested PWM Driver (not included in IRPLLED1A kit external supply for VCC is used, the minimum amount of dimming achievable (light output approaches 0%) will be determined by the “on” time of the HO output, when in a fully functional regulating state. To maintain reliable dimming recommended to keep the “ ...
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HO “on” time will be 2.7µs (one-fourth of the period – see calculations below) according to standard buck topology theory. This will set the minimum “off” time of the enable signal to 27µs. Duty the ...
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During PWM dimming operation care should be taken to avoid high current pulses occurring in the LED output at the start of each dimming period. This occurs only when a capacitor is connected to the output, that is when the ...
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... An alternative method of achieving the same thing is to add a hysteresis resistor from the LO output to the IFB input. It should be noted that the IRPLLED1A reference design board reflects the schematic of Figure 16 where a high speed diode is used in place of the lower MOSFET switch indicated in Figure 1. ...
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... This circuit reacts very rapidly when the output voltage exceeds the predetermined level. It operates whether or not an output capacitor is connected, i.e. in any of the alternative JDIM jumper positions. The over voltage protection threshold has been set to 32V in the IRPLLED1A Rev D demo board to allow one or two standard LED panels to be connected in series to the output before reaching a voltage level high enough to trigger the protection circuit ...
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... COUT in cases where the bus voltage is greater than the rating of this capacitor. Note: The over voltage protection scheme used in the IRPLLED1A evaluation board is different to that used in earlier revisions of the IRPLLED1A and does not conflict with the synchronization operation described in the previous section. ...
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The yellow waveform shows the output voltage and the red waveform shows the VS switching waveform. In this example there is no output capacitor. When the output goes above the over voltage threshold the VCC voltage shown in blue is ...
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... EMC performance. EMC performance The IRPLLED1A evaluation board has not been EMC tested. Input and Output filters can be used to reduce the conducted emissions to below the limits of the applicable EMC standard as needed. Inductors may require a powdered Iron core rather than Ferrite, it can handle a much larger current before saturating. If EMC is of critical importance, it may be beneficial to use a MOSFET for the upper switching element and a diode for the lower switch ...
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... Phoenix Passive IRS25401/11 IR 2-641260-1 Amp LM431BIM3N1C National Semi PN2907A Fairchild IRFB17N20D IR 5005 Keystone 5006 Keystone 5009 Keystone 7-340-1PP-BA IERC IRPLLED1A Rev D 929836-09-05-ND 3M 929836-09-02-ND 3M STC02SYAN Sullins Connectors SP600-54 Berquist 3049 Berquist H346-ND Building Fasteners H216-ND Building Fasteners RD-0608 # of Reference devices 1 CVCC1 ...
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Enable Signal Generator (not included) Device Item Description Type 1 C 10uF, 25V, Radial ECEA1EKG100 2 C 100nF, 50V, 0805 VJ0805Y104KXATW1BC 3 C 1nF, 50V, 0805 VJ0805Y102KXACW1BC 4 D Mini Melf LL4148 5 R 1k, 1%, 0805 MRC10EZHF1001 6 R ...
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Bottom Overlay IR WORLD HEADQUARTERS: 101 N. Sepulveda Blvd., El Segundo, California 90245 Tel: (310) 252-7105 www.irf.com Bottom Metal Data and specifications subject to change without notice. RD-0608 11/04/2011 28 ...