IRPLLED1 International Rectifier, IRPLLED1 Datasheet
IRPLLED1
Specifications of IRPLLED1
Related parts for IRPLLED1
IRPLLED1 Summary of contents
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... IRPLLED1 (Rev D Version) 350mA to 1.5A High Voltage LED Driver using IRS2540,1 or IRS25401,11 1. Introduction………………………………………………………………...….1 2. Constant Current Control.......................................................................3 3 ...
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... Important Safety Information The IRPLLED1 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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Constant current control The IRS2540/1/01/ 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. This feedback signal is compared to an internal ...
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Fig. 3 IRS2540/1/01/11 Control Signals, Iavg=1.2A The switching continues to regulate the current at an average value determined as follows: when the output combination of L1 and COUT is large enough to maintain a low ripple on IFB (less than ...
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Since some of these equivalent values of resistance are not available, series and parallel combinations are used and are specified as follows (all combinations use standard value resistors: 1.43Ω, 0.56Ω, and 0.47Ω): = 43 Ω 350mA = ...
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Fig. 6 Vbus = 100V 470uH, COUT = 33uF 3. Frequency selection The frequency in the IRS2540/1/01/11 application is free running and maintains current regulation by quickly adapting ...
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Fig. 7 Iout = 350mA, Vout = 16.8V, COUT = 0uF 400 390 380 370 360 350 340 330 30 Fig. 8 Iout = 350mA, Vout = 16.8V, COUT = 0uF www.irf.com 80 ...
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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 IRPLLED1 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 IRPLLED1 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 IRPLLED1 Rev D 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 IRPLLED1 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 IRPLLED1 board allows for an additional MOSFET switch added. In this case, during the dead time, instead of the body diode free-wheeling 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 a simple enable pin dimming signal generator. VBUS COM Fig. 22 Suggested PWM Driver (not included in IRPLLED1.5X2 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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... This current spike stresses the load possibly decreasing LED operating lifetime. The IRPLLED1 includes a jumper setting to define whether or not the board is being used in the dimming mode. This two position jumper allows the designer to either include or exclude the resistor Rout, which is in series with the output capacitor ...
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The presence of such current spikes may cause the inductor to hum or buzz where the emitted sound will be that of the dimming frequency. The inrush of current ...
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... PWM dimming signal will still be the dominant factor of the overall output current regulation capabilities. It should be noted that the IRPLLED1 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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... The revised IRS25401 and IRS25411 contain internal circuitry to protect against possible latch up conditions and do not require RSYNC and DSYNC. Fig. 28a: Dimming Synchronization Waveforms. 9. Open circuit protection Fig. 29 IRPLLED1 Improved Open Circuit Protection Scheme www.irf.com RD-0608 22 ...
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... JDIM jumper positions. The over voltage protection threshold has been set to 32V in the IRPLLED1 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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Fig. 30 Open Circuit Fault Signals, with Clamp 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 ...
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... EMC performance. EMC performance The IRPLLED1 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, which 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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It’s a general rule of thumb that all components associated with the IC should be connected to the IC ground with the shortest path possible. 6. All traces carrying the load current need to be adjusted accordingly. 7. Gate drive ...
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... Phoenix Passive IRS2540/1/01/11 IR 2-641260-1 Amp LM431BIM3N1C National Semi PN2907A Fairchild IRFB17N20D IR 5005 Keystone 5006 Keystone 5009 Keystone 7-340-1PP-BA IERC IRPLLED1 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 www.irf.com Bottom Metal RD-0608 29 ...
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... Section 8 "Dimming Mode" now recommends a PWM frequency of 1kHz for dimming. Added additional comments in "Layout Considerations" item (5) Now updated for Rev D of the IRPLLED1 demo board. Introduction – added safety warning. Minor updates to sections (1) through (8) Modified Fig 1 to remove old over voltage protection Rev 4 ...