IR2157_07 IRF [International Rectifier], IR2157_07 Datasheet
IR2157_07
Related parts for IR2157_07
IR2157_07 Summary of contents
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FULLY INTEGRATED BALLAST CONTROL IC Features Programmable preheat time & frequency Programmable ignition ramp Protection from failure-to-strike Lamp filament sensing & protection Protection from operation below resonance Protection from low-line condition & automatic restart (mimics a magnetic ballast) Description The ...
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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 2 I ...
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Absolute Maximum Ratings Absolute maximum ratings indicate sustained limits beyond which damage to the device may occur. All voltage param- eters are absolute voltages referenced to COM, all currents are defined positive into any lead. The thermal resistance and power ...
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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 ...
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Electrical Characteristics (cont.) Floating Supply Characteristics Symbol Definition I Quiescent V supply current QBS0 BS I Quiescent V supply current QBS1 BS VBSMIN Minimum required VBS voltage for proper HO functionality I Offset supply leakage current LK Oscillator I/O Characteristics ...
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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 ...
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Lead Assignments & Definitions Lead # Symbol Description bus sensing input Preheat timing capacitor Preheat frequency resistor & ignition capacitor Oscillator timing resistor T 5 RUN Run frequency ...
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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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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 VCC should be bypassed to COM as close to the ...
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IR2157 The Control Sequence & Timing Component Selection The IR2157 uses the following control sequence (Figure 3) to drive rapid start fluorescent lamps. f Start min ...
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RDT (Kohms) Figure 5: Deadtime versus ...
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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 ...
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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 ...
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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 pin contains an internal 7.5V zener diode clamp, thereby ...
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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 ...
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MOSFET) serves as the power supply to the upper gate driver CMOS circuitry. Since the quiescent current in this CMOS circuitry is very low (typically 45mA in ...
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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 53.5 T ...
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VCC (volts) Figure 31: t rise versus V and temperature CC 0.235 T = -25C 0. 25C T = 75C 0.225 T = ...
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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 ...