ml4835 Microsemi Corporation, ml4835 Datasheet
ml4835
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ml4835 Summary of contents
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... Compact Fluorescent Electronic Dimming GENERAL DESCRIPTION The ML4835 is a complete solution for a dimmable or a non-dimmable, high power factor, high efficiency electronic ballast especially tailored for a compact fluorescent lamp (CFL). The Bi-CMOS ML4835 contains controllers for “boost” type power factor correction as well as for a dimming ballast with end-of-lamp life detection ...
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... External resistor which SETS oscillator SET F , and R /C MAX Oscillator timing component to set T2 start frequency Oscillator timing components ML4835 20-Pin SOIC (S20) 20-Pin DIP (P20) PVFB/OVP 1 20 PEAO 2 19 PIFB 3 18 PIFBO 4 17 LAMP LEAO 6 15 ...
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... PFC OVP COMPARATOR OVP Threshold Hysteresis Propagation Delay Junction Temperature .............................................. 150ºC Storage Temperature Range ...................... –65ºC to 150ºC Lead Temperature (Soldering, 10 sec) ..................... 260ºC Thermal Resistance ( ML4835CP .......................................................... 65ºC/W 65mA ML4835CS .......................................................... 80ºC/W OPERATING CONDITIONS Temperature Range ....................................... 0°C to 85°C –0.5V 11. 15. ...
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... ML4835 ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER OSCILLATOR Initial Accuracy (F ) MIN Voltage Stability (F ) MIN Temperature Stability (F ) MIN Total Variation (F ) MIN Initial Accuracy (START) Voltage Stability (START) Temparature Stability (START) Total Variation (START) Ramp Valley to Peak Initial Accuracy (Preheat) Total Variation (Preheat) C Discharge Current ...
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... Note 1: Limits are guaranteed by 100% testing, sampling, or correlation with worst case test conditions. (Continued) CONDITIONS = 10µ 20mA OUT I = 200mA OUT I = 20mA OUT I = 200mA OUT I = 10mA, V < V OUT CC CC START CL=1000pF ICC=15mA ) V –0.2V CC START (V –0.5V), INTERRUPT = –0.5V) CC ML4835 MIN TYP MAX UNITS 0.86 s 0.72 s 5.9 s -50 -54 -58 µA 0.4 0.7 1.0 V 7.0 7.3 7.8 V 1.6 1.75 1.9 V 4.4 4.65 4.9 V 6.2 6.6 6 ...
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... VCO frequency range. This allows for the used with a variety of different output networks. Figure 1 depicts a detailed block diagram of ML4835. The ML4835 provides several safety features. See the corresponding sections for more details: REF REF_OK 20 ...
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... CLK PFC OUT (Continued) POWER FACTOR SECTION The ML4835 power factor section is a peak or average current sensing boost mode PFC control circuit in which only voltage loop compensation is needed simpler than a conventional average current control method. It consists of a voltage error amplifier, a current sense amplifier (no compensation is needed), an integrator, a comparator, and a logic control block ...
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... OUT OUT ! Where t is the dead time. POWER LEVEL ML4835 TRIP POINT POWER SHUTOFF Figure 4. Simplified Model of ML4835 EOL Functionality PVFB/OVP 1 – 2. Figure 5. Compensation Network 8 (Continued) OVERVOLTAGE PROTECTION AND INHIBIT The OVP pin serves to protect the power circuit from being subjected to excessive voltages if the load should change suddenly (lamp removal) ...
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... NOTE 1: R SHOULD BE SELECTED SUCH THAT AFTER PREHEAT WITH LEA_ENB "HI", SET I MUST BE < 0. CHG UNI-DIRECTIONAL SOURCE CURRENT ONLY. CHG t t DIS CHG Waveforms when the ML4835 is Started with a Bleed Resistor from ML4835 2.5V I CHG = RSET 5V 7.5V I CHG = – RSET 8K±25% 5V – ...
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... EOL and the ML4835 The ML4835 uses a circuit that creates a DC voltage representative of the power supplied to the lamps through the inverter. This voltage is used by the ML4835 to latch off the ballast when it exceeds an internal threshold. An external resistor can be used as the “EOL latch resistor” to set the power level trip point, as shown Figure 12 ...
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... This allows the IC to start using a “bleed resistor” from the rectified AC line. To help reduce ballast cost, the ML4835 includes a temperature sensor which will inhibit ballast operation if the IC’s junction temperature exceeds 130°C. In order to ...
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... ML4835 TYPICAL APPLICATIONS The ML4835 can be used for a variety of lamp types compact fluorescent lamps IEC T8 (linear lamps) T5 linear lamps T12 linear lamps HEAT LEA_ENB OR DIMMING LOCKOUT INTERRUPT INHIBIT 12 The ML4835 can also be used for dimming applications. For example, 20:1 dimming can be achieved using the ML4835 with external dimming units ...
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... U2A 3 + 1.5k 16. – 220k U2B – 220pF C3, 1nF 0.01µF ML4835 D16, 0.1A, 75V R11 T3 150 Q2 C12 2.5A, 500V 4 0.33µF 3 D17, 0.1A, 75V 2 6 D19 600V R12 9 C11 150 Q3 6800pF 2.5A, 500V D15 8 1A C14 600V 0.015µF ...
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... Q1 R25 C8 4.5A, 500V 100 2 47µ 100µF R7 D18 432k 7 0.1A D11, 15V, 0.5W 75V 1 R3 820 R8 8 5.76k R9 C9 4.3 1µF ML4835 R10 R24 20 REF 20k PFC OUT 17 OUT A 16 OUT GND C26 14 A GND 47µF 13 RAMP 12 PW DET 11 RX/CX C25 0.22µ ...
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... OUT GND C26 14 A GND 47µF 13 RAMP 12 PW DET 11 RX/CX C25 0.22µF R23, 200k C24 C27 R22 C23 C21 470pF 0.22µF 6.8µF 15µF ML4835 R11 T3 150 Q2 C12 2.5A, 500V 4 C30 0.33µF 120pF 3 D17, 0.1A, 75V 2 6 C28 D19 120pF R12 600V 9 C11 ...
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... ML4835 PHYSICAL DIMENSIONS 0.498 - 0.512 (12.65 - 13.00) 20 PIN 0.024 - 0.034 0.050 BSC (0.61 - 0.86) (1.27 BSC) (4 PLACES) 0.012 - 0.020 0.090 - 0.094 (0.30 - 0.51) (2.28 - 2.39) 20 PIN 0.060 MIN (1.52 MIN) (4 PLACES) 0.170 MAX (4.32 MAX) 0.125 MIN (3.18 MIN) 16 inches (millimeters) Package: S20 20-Pin SOIC 0.291 - 0.301 0.398 - 0.412 (7.39 - 7.65) (10.11 - 10.47) 0.095 - 0.107 (2 ...
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... PHYSICAL DIMENSIONS ORDERING INFORMATION PART NUMBER ML4835CP (End Of Life) ML4835CS (End Of Life) © Micro Linear 1999 registered trademark of Micro Linear Corporation. All other trademarks are the property of their respective owners. Products described herein may be covered by one or more of the following U.S. patents: 4,897,611; 4,964,026; 5,027,116; 5,281,862; 5,283,483; 5,418,502; ...