IR21571 International Rectifier, IR21571 Datasheet
IR21571
Specifications of IR21571
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IR21571 Summary of contents
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... The heart of this control variable frequency oscillator with externally programmable deadtime. Precise control of a 50% duty cycle is accomplished using a T-flip-flop. The IR21571 is available in both 16 pin DIP and 16 pin narrow body SOIC packages. Typical Connection ...
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... IR21571 (S) & (PbF) Absolute Maximum Ratings Absolute maximum ratings indicate sustained limits beyond which damage to the device may occur. All voltage parameters are absolute voltages referenced to COM, all currents are defined positive into any lead. The thermal resistance and power dissipation ratings are measured under board mounted and still air conditions. ...
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... C = 470 pF, RPH and RUN leads no connection 0.0V 1000pF Min. Typ. 10.5 11.4 1.5 1.8 50 150 75 200 2.9 3.8 4.0 5.5 14.5 15.6 IR21571 (S) & (PbF) Min. Max. Units CLAMP V -3.0 600 V V CCUV+ CLAMP Note VCC V 220 — pF — ...
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... IR21571 (S) & (PbF) Electrical Characteristics (cont 14V +/- 0.25V BIAS 20. 0.5V Floating Supply Characteristics Symbol Definition I Quiescent V supply current QBS0 BS I Quiescent V supply current QBS1 BS I Offset supply leakage current LK Oscillator I/O Characteristics Symbol Definition fosc Oscillator frequency d Oscillator duty cycle ...
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... Min. Typ. — 0 — CCUV- IR21571 (S) & (PbF) = 0.0V, CPH o C unless otherwise specified. Max. Units Test Conditions 0 RUN 5V 2V > TSD Max. Units Test Conditions 2.3 V 200 mV 1.21 V 0.26 ...
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... IR21571 (S) & (PbF) Functional Block Diagram 3.0V VDC 1 5.1V 1.0uA CPH 2 10V 5.1V 4.0V 4.0V RPH 3 2. 2.0V RUN 50uA UNDER- VOLTAGE OC 8 DETECT 7.6V Lead Assignments & Definitions VDC CPH 2 15 RPH VCC 5 12 RUN COM LEVEL R Q SHIFT CLK ...
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... T > 160C J (Over-Temperature) CS > CS+ Threshold (Over-Current or Hard Switching < 0.2V (No-Load or Below Resonance > 160C J (Over-Temperature) www.irf.com IR21571 (S) & (PbF) Power Turned On UVLO Mode 1 / -Bridge Off 2 I 150 A QCC CPH = 0V Oscillator Off VCC > 11.4V (UV+) and VDC > 5.1V (Bus OK) and SD < 1.7V (Lamp OK) ...
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... IR21571 (S) & (PbF) Description of Operation & Component Selection Tips Supply Bypassing and PC Board Layout Rules Component selection and placement on the pc board is extremely important when using power control ICs. V should be bypassed to COM as close CC to the IC terminals as possible with a low ESR/ESL capacitor, as shown in Figure 1 below. ...
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... LC component tolerances (please note that it is possible to use the IR21571 in systems where fstart > fph > fign > frun, simply by leaving the RUN lead open). Six leads in the IC are used to control the Startup, ...
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... IR21571 (S) & (PbF) 10 tDEAD (usec RDT (Kohms) Figure 5: Deadtime versus R CPH RPH IGN RUN RUN START START Figure 6: Oscillator section block diagram with external component connection 10 During the Startup Mode, the operating frequency is determined by the parallel combination and R START C and shown in Figure 6 ...
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... PH Figure 8: fosc versus effective R 250 200 150 FREQ (KHz) 100 50 resistor and R , RUN T . RUN Figure 9: fosc versus effective R IR21571 (S) & (PbF) resistance (i.e., T CT=220pF,RDT=11K CT=470pF,RDT=6.2K CT=1nF,RDT= ohms 2.0 usec) T DEAD CT=220pF, RDT=5.6K CT=470pF, RDT=2.7K CT=1nF, RDT=1. ohms ...
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... IR21571 (S) & (PbF) Lamp Protection & Automatic Restart Circuitry Operation Three leads on the IR21571 are used for protection, as shown in Figure 10 below. These are V monitor), S (unlatched shutdown BUS VDC 3. 5. CPH 1.0uA 2 7.6V 5.1V 4. 50uA 8 7. Figure 10: Lamp protection & automatic restart circuitry block diagram with external component connection. ...
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... Since a lamp fault would normally lead to a lamp exchange, when a new lamp is inserted into the fixture, the SD lead would be pulled back to near the ground potential. Under these www.irf.com IR21571 (S) & (PbF) VDC CPH ...
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... IR21571 (S) & (PbF) Thus, for a lamp removal and replacement, the ballast automatically restarts the lamp in the proper manner, maximizing lamp life and minimizing stress on the power MOSFETs or IGBTs. The SD lead contains an internal 7.5V zener diode clamp, thereby reducing the number of external components required. ...
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... Figure 16: Hard switching condition Figure 17: Operation below resonance www.irf.com IR21571 (S) & (PbF) Figure 18: Auto restart for lamp replacement Recovery from such a fault condition is accomplished by cycling either the SD lead or the V a lamp is removed, the SD lead goes high, the fault latch is reset, and the chip is held off in an unlatched state ...
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... IR21571 (S) & (PbF) rectifie d +V BUS AC line VDC GHS CPH BOOT R RPH VB SUPPLY BOOT RT VCC 4 13 RUN COM C VCC GLS return BUS Figure 19: Typical bootstrap supply connection with V charge pump from half-bridge output CC (shaded area) A high voltage, fast recovery diode D called bootstrap diode) is connected between V ...
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... Case outlines www.irf.com IR21571 (S) & (PbF) 16-Lead PDIP 16-Lead SOIC (narrow body) 01-6015 01-3065 00 (MS-001A) 01-6018 01-3064 00 (MS-012AC) 17 ...
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... SPN code) Assembly site code Per SCOP 200-002 Leadfree Part 16-Lead PDIP IR21571 order IR21571PbF 16-Lead SOIC IR21571S order IR21571SPbF Description of Change “Not Recommended for new design: Please use IRS21571D” Data and specifications subject to change without notice. IR logo 6/10/2008 www ...