IR2157 International Rectifier Corp., IR2157 Datasheet
IR2157
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IR2157 Summary of contents
Page 1
... The heart of this control variable frequency oscillator with externally programmmable deadtime. Precise control of a 50% duty cycle is accomplished using a T-flip-flop. The IR2157 is available in both 16 pin DIP and 16 pin narrow body SOIC packages. Typical Connection ...
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... IR2157 SD > 2. VCC < 9.5V (Power Turned Off) FAULT Mode T > 175C J (Over-Temperature) Fault Latch Set 1 / -Bridge Off Oscillator Off CS > 1.0V (Failure to Strike Lamp or Hard Switching > 175C ...
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... Please note that this supply pin should not be driven by a DC, low impedance power source greater than the V specified in the Electrical Characteristics section. CLAMP ADVANCED INFORMATION +25°C (16 lead PDIP) A (16 lead SOIC) (16 lead PDIP) (16 lead SOIC) and COM which has a nominal breakdown CC 3 IR2157 Min. Max. Units -0.3 625 0 ...
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... IR2157 Recommended Operating Conditions For proper operation the device should be used within the recommended conditions. Symbol Definition V High side floating supply voltage Steady state high side floating supply offset voltage S V Supply voltage CC I Supply current lead voltage DC DC ...
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... Min. Typ. Max. — 1.0 — — 4.0 — — — 5.15 — — 7.6 — 0 — 5 IR2157 Units Test Conditions 600V B S Units Test Conditions R = 32k , 6. =470pF T kHz ...
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... IR2157 Electrical Characteristics (cont.) Characteristics RPH Symbol Definition I Open circuit RPH pin leakage current RPHLK V Fault-mode RPH pin voltage RPHFLT Characteristics RUN Symbol Definition I Open circuit RUN pin leakage current RUNLK V Fault-mode RUN pin voltage RUNFLT Protection Circuitry Characteristics Symbol Definition ...
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... IR2157 & SHIFT ...
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... IR2157 ADVANCED INFORMATION 16 Lead SOIC (narrow body) 16 Lead PDIP 8 01-3064 00 01-3065 00 ...
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... Figure 2: COM pin connection PCB layout example These connection technique prevents high current ground loops from interfering with sensitive timing component operation, and allows the entire control circuit to reject common-mode noise due to output switching. 9 IR2157 pin 1 C (surface mount) VCC C (through hole) ...
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... LC component tolerances (please note that it is possible to use the IR2157 in systems where fstart > fph > fign > frun, simply by leaving the RUN pin open). Six pins in the IC are used to control the Startup, ...
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... Typically, a 4.5:1 ratio of 100 IR2157 ...
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... IR2157 the hot filament-to-cold filament resistance is desired for maximum lamp life, as shown in Figure 7 Figure 7: Lamp filament voltage during the preheat, ignition ramp and run modes. The Preheat Time is programmed by means of the preheat capacitor, CPH, an internal 1mA current source, and an internal threshold on the CPH pin of 4 ...
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... Lamp Protection & Automatic Restart Circuitry Operation Three pins on the IR2157 are used for protection, as shown in Figure 10 below. These are VDC (dc bus monitor), SD (unlatched shutdown), and CS (latched shutdown ...
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... IR2157 RUN mode Low VDC Figure 11: VDC pin fault and auto restart Lamp Presence Detection and Automatic Restart The second protection pin, SD, is used for both unlatched shutdown and automatic restart functions. ...
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... Figures 15, 16 and 17 are oscillographs of fault conditions. Figure 15 shows a failure of the lamp to strike, Figure 16 shows a hard switching condition and Figure 17 shows an under-current condition. Figure 15: Lamp failure to strike 1 / Bridge output Figure 16: Hard switching condition 15 IR2157 ...
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... IR2157 Figure 17: Operation below resonance Figure 18: Auto restart for lamp replacement ADVANCED INFORMATION Recovery from such a fault condition is accomplished by cycling either SD pin or the VCC pin. When a lamp is removed, the SD pin goes high, the fault latch is reset, and the chip is held off in an unlatched state ...
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... Figure 22 Iqcc (mA - 25C T = 75C T = 125C 5 0 14.5 14.5 Figure 24 IR2157 C (surface mount (surface mount) Boot C (through hole) VCC C (surface mount) VCC 25C T = 75C T = 125C VCC (volts) versus V and temperature ...
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... IR2157 12 11.5 Vccuv+ 11 Vccuv (V) 10.5 10 Vccuv- 9 Temperature (C) Figure 25: V and V versus temperature CCUV+ CCUV -25C 53. 25C T = 75C 53 125C 53.25 fOSC 53 (KHz) 52.75 52.5 52. 11.5 12 12.5 13 13.5 VCC (volts) Figure 27: f versus V and temperature OSC CC (RT=330k , CT=300pF) 1000 990 980 970 960 tDEAD 950 ...
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... Figure 34: SD+ threshold versus V 5 -25C T = 25C 5. 75C T = 125C 5.3 5.25 VDC+ (volts) 5.2 5.15 5 11.5 Figure 36: VDC+ threshold versus V 19 IR2157 T = -25C T = 25C T = 75C T = 125C 12 12.5 13 13.5 14 14.5 VCC (volts) and temperature -25C T = 25C T = 75C T = 125C 12 12.5 13 13.5 14 14.5 VCC (volts) and temperature CC ...
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... IR2157 3.3 3.25 3.2 VDC- 3.15 (volts) 3.1 3. 11.5 12 12.5 13 13.5 VCC (volts) Figure 37: VDC- threshold versus V CC 5.25 5.2 5.15 VCPHRUN (volts) 5.1 5. 11.5 12 12.5 13 13.5 VCC (volts) Figure 39: V threshold versus V CPHRUN temperature WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245 Tel: (310) 322 3331 IR GREAT BRITAIN: Hurst Green, Oxted, Surrey RH8 9BB, UK Tel 1883 732020 IR GERMANY: Saalburgstrasse 157, 61350 Bad Homburg Tel 6172 96590 IR FAR EAST: K& ...