1. Variable Switching Power Supply Schematic

The SG3525A series of pulse width modulator integrated circuits are designed to offer improved performance and lowered external parts count when used in designing all types of switching power supplies. The on-chip + 5.1 V reference is trimmed to ±1% and the input common-mode range of the error amplifier includes the reference voltage eliminating external resistors. A sync input to the oscillator allows multiple units to be slaved or a single unit to be synchronized to an external system clock. A single resistor between the C T and the discharge terminals provide a wide range of dead time ad- justment.These devices also feature built-in soft-start circuitry with only an external timing capacitor required. A shutdown terminal controls both the soft-start circuity and the output stages, providing instantaneous turn off through the PWM latch with pulsed shutdown,as well as soft-start recycle with longer shutdown commands. These functions are also controlled by an undervoltage lockout which keeps the outputs off and the soft-start capacitor discharged for sub-normal input voltages. Jamstix seriale. This lockout circuitry includes approximately 500 mV of hysteresis for jitter-free operation.

Variable Switching Power Supply Schematic

Another feature of these PWM circuits is a latch following the comparator. Once a PWM pulses has been terminated for any reason,the outputs will remain off for the duration of the period. The latch is reset with each clock pulse. The output stages are totem-pole designs capable of sourcing or sinking in excess of 200 mA. The SG3525A output stage features NOR logic, giving a LOW output for an OFF state.Key Features.

IR International Rectifierwww.irf.com.Name & variantsSymbolPackagefluorescent lampVariants:Synchronous Buck Multiphase Optimized BGA Power BlockSource: www.irf.com/product-info/datasheets/data/ip2002.pdfVariants:Variants:Variants:Variants:Variants:Variants:Variants:Variants:Variants:Variants:Variants:Variants:ADAPTIVE BALLAST CONTROL ICThe IR2520D(S) is a complete adaptive ballast controller and 600V half-bridge driver integrated into a single IC for fluorescent lighting applications.Data Sheet No. PD60212 Rev ASource: www.irf.com. Ir2520.pdfVariants:DUAL LOW SIDE DRIVERSource: ID4426.pdfVariants:DUAL LOW SIDE DRIVERSource: ID4426.pdfVariants:DUAL LOW SIDE DRIVERSource: ID4426.pdfVariants:Variants:Variants:THREE PHASE BRIDGESource: Power BlockSource: www.irf.com/product-info/datasheets/data/ip2002.pdffluorescent lampDual In Line PackageDual In Line PackageDual In Line Package8 Lead SOICData Sheet No. PD60212 Rev ASource: www.irf.com. Ir2520.pdfSmall Outline package 150 milSmall Outline package 150 mil.