ml4831 Microsemi Corporation, ml4831 Datasheet
ml4831
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ml4831 Summary of contents
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... GENERAL DESCRIPTION The ML4831 is a complete solution for a dimmable, high power factor, high efficiency electronic ballast. Contained in the ML4831 are controllers for “boost” type power factor correction as well as for a dimming ballast. The Power factor circuit uses the average current sensing method with a gain modulator and over-voltage protection ...
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... LFB OUT Output from the Lamp Current Error Transconductance Amplifier used for lamp current loop compensation 7 R(SET) External resistor which sets oscillator F , and R(X)/C(X) charging current MAX 2 ML4831 18-Pin DIP (P18) EA–/OVP EA OUT OUT REF I(SINE) VCC ...
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... Maximum Forced Voltage (Pin 2) .................. –0. Junction Temperature ............................................. 150 C Storage Temperature Range ..................... – 150 C Lead Temperature (Soldering 10 Sec.) ..................... 260 C Thermal Resistance ( Plastic DIP–P ................................................... 70 C/W OPERATING CONDITIONS Temperature Range ML4831C .................................................. Junction Operating Temperature Range, J CONDITIONS I = 0mA 0V, SINE PIN1 V = – ...
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... ML4831 ELECTRICAL CHARACTERISTICS PARAMETER Oscillator Initial accuracy Voltage stability Temperature stability Total Variation Ramp Valley to Peak C(T) Charging Current (FM Modes) C(T) Discharge Current Output Drive Deadtime Reference Section Output Voltage Line regulation Load regulation Temperature stability Total Variation Output Noise Voltage Long Term Stability Short Circuit Current Preheat and Interrupt Timer (Pin 10) (R(X) = 590K , C( ...
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... This allows for the used with a variety of different output networks. POWER FACTOR SECTION The ML4831 Power Factor section is an average current sensing boost mode PFC control circuit which is architecturally similar to that found in the ML4821. For detailed information on this control architecture, please refer to Application Note 16 and the ML4821 data sheet ...
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... The compensation network shown in Figure 2 will introduce a zero and a pole at: 2.5V OSC PREHEAT TIMER + R S – Q PWM (PFC – 2.75V + OVP Figure 1. ML4831 Block Diagram – Figure 2. Compensation Network LFB OUT + 2 ...
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... Capacitor C1 as shown in Figure 2 is used to block the DC current to minimize the adverse effect of offsets. Slew rate enhancement is incorporated into all of the operational transconductance amplifiers in the ML4831. This improves the recovery of the circuit in response to power up and transient conditions. The response to large signals will be somewhat non-linear as the transconductance amplifiers change from their low to high transconductance mode ...
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... CHG 1.3mA (7) Figure 6. Typical V the ML4831 is Started with a Bleed Resistor from the Rectified AC Line and Bootstrapped from an value and lower R T STARTING, RE-START, PREHEAT AND INTERRUPT The lamp starting scenario implemented in the ML4831 is designed to maximize lamp life and minimize ballast heating during lamp out conditions ...
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... The C(X) pin is clamped to about 7.5V. A summary of the operating frequencies in the various HEAT operating modes is shown below. Operating Mode DIMMING LOCKOUT Preheat R INHIBIT Dimming Q Lock-out S Dimming Control Figure 8. Lamp Starting and Restart Timing ML4831 Operating Frequency [F(MAX) to F(MIN)] 2 F(MIN) F(MIN) to F(MAX) 9 ...
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... ML4831 APPLICATIONS POWER FACTOR CORRECTED FLUORESCENT DIMMING LAMP BALLAST Figure 9. Typical Application: 2-Lamp Isolated Dimming Ballast with Active Power Factor Correction for 120VAC Input 10 ML4831 ...
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... TABLE 1: PARTS LIST FOR THE ML4831EVAL EVALUATION KIT CAPACITORS QTY. REF. DESCRIPTION 2 C1, 2 3.3nF, 125VAC, 10%, ceramic, “Y” capacitor 1 C3 0.33 F, 250VAC, “X”, capacitor 4 C4 0.1 F, 50V, 10%, ceramic capacitor 2 C5, 21 0.01 F, 50V, 10%, ceramic capacitor 1 C6 1.5 F, 50V, 2.5%, NPO ceramic capacitor 2 C7, 12 ...
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... ML4831 TABLE 1: PARTS LIST FOR ML4831EVAL EVALUATION KIT RESISTORS: (Continued) QTY. REF. DESCRIPTION 4 R14, 17, 24, 25 100K, 1/4W, 5%, carbon film resistor 1 R15 681K, 1/4W, 5%, carbon film resistor 1 R16 10K, 1/4W, 1%, metal film resistor 1 R21 33 , 1/4W, 5%, carbon film resistor 1 R23 25K, pot (for dimming adjustment) DIODES: ...
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... TABLE 1: PARTS LIST FOR ML4831EVAL EVALUATION KIT MAGNETICS: (Continued) QTY. REF. DESCRIPTION Inductor, L PRI E24/25 core set, TDK PC40 material 10 pin horizontal bobbin (Plastron #0722B-31-80) Wind as follows: 1st: 170T of 25AWG magnet wire; start pin #10, end pin #9. 1 layer of mylar tape 2nd #32 magnet wire ...
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... MAX) 0.125 MIN (3.18 MIN) ORDERING INFORMATION PART NUMBER ML4831CP © Micro Linear 1997 is a registered trademark of Micro Linear Corporation Micro Linear Products described in this document may be covered by one or more of the following patents, U.S.: 4,897,611; 4,964,026; 5,027,116; 5,281,862; 5,283,483; 5,418,502; 5,508,570; 5,510,727; 5,523,940; ...