The new high voltage integrated circuit paves the way for that the ballast is designed by djsgjg0045


									The new high voltage integrated circuit paves the way for that the ballast is designed
In recent years, the electronic ballast which uses integrated circuit of the control
device and MOSFET transistor-resistor logic is customary, this is because of
strengthening start-up control and protecting the function, and compared with
ordinary autooscillation type bipolar transistor ballast, its reliability is excellent.
However, until nowadays, in terms of size and number of elements, the autooscillation
type transistor-resistor logic ballast stills have its strong point. Recently, as the
international rectifier company introduces the high voltage integrated circuit IR2520D,
this situation changes to some extent. Here, let's see this product, and introduce the
new reference design, this simplify used for European market the intersection of
lighting and design of ballast greatly.
IR2520D of the international rectifier company of integrated circuit of ballast control
of the Model IR2520D is for overcoming the shortcoming of the autooscillation type
ballast designed with the discrete component, Essential function that IR2520D
includes preheating, lighting, light error protection of normal operation, CFL,
exchanges low voltage protection of electric wire netting to wait a moment, and the
high pressure in 600 V half bridge converter and undervoltage driver. Though
IR2520D has integrated a lot of functions, only eight of its draw the foot, use canonial
SO8 or DIP8 to capsulate, there are only 20 components at most to can reduce the
number of elements of the whole ballast to.
Fig. 1
It is a block diagram of IR2520D. The key component of this kind of device is a
voltage controlled oscillator (VCO) ,Can adjust the frequency to most outside low
(Fmin) ,And a simulation voltage from 0 V to 5 V is input. A VS (ZVS) that this
integrated circuit includes meeting the formula And non-zero VS (non-ZVS)
Protection. A maximum advantage of IR2520D is that there is shut-down function that
electric current form factor controls inside it, not needing to detect the high-accuracy
resistor of the electric current, this resistor is generally used for measuring current
overload. The integrated circuit carry on current overload protection with the
intersection of VS and pin and the intersection of half bridge converter and
undervoltage the intersection of MOSFET and RDSon of transistor-resistor logic, and
measure the non-zero VS state. 600 V FET transistor-resistor logic inside the device
couples VS pin to VS sense slowdown monitoring circuit, and when LO pin is in the
high level, can measure VS pin accurately, in periodic remaining half switches, FET
transistor-resistor logic is turned on by the high pressure at the same time, VS is at the
direct-flow mother's collinear electric potential, can bear the direct current power
supply mother's collinear upper voltage.
Design the design that is carried on with IR2520D to be very simple with IR2520D,
because it has two control pins only: VCO (the input voltage of the Shaker is
direct-flow 0-5 V) And FMIN. While using designing for the light different in power,
only need to revise several and connecting the component.
FMIN pin passes a resistor (RFMIN) Earth. The number value of resistor confirm low
frequency FMIN and original frequency the most of the integrated circuit ' It is
probably 2.5 More in my blog

To top