On the occasion of the acquired portable led lantern with Chinese production the battery inside. The flashlight can also switch between cluster eight super-bright led and krypton lamp filament voltage 5,4 V. also located Inside the charger for the battery. Except the light combined with the lamp - a fluorescent light power 6 W, eating using a special voltage Converter 150 - 6th Century
Backlight with energy saving lamps (hereinafter EL) type Osram Dulux S7W, implemented in this design, very convenient for many purposes. Using it is possible to read in a tent on a camping trip, in field conditions continuously for six hours - the low power consumption of the lamp provided a fully charged internal battery. Test lamp and its lamp with energy saving bulb "strength" was carried out by me in the countryside throughout the year. Schematic Converter voltage seems to me very good and valuable for replication in other designs, and for use of the finished card Converter to power E power up to 8 W - in aquarium lamp. Electric circuit device Converter, copied from the printed circuit Board and is presented on the figure.
The principle of operation of the device. The device implemented according to the scheme of two-stroke pulsed voltage Converter, operates with a frequency of about 112 kHz. In the basis of the TL494 chip - ready pulse width modulator signals, so scheme and device, overall it is very simple. The circuit output a high voltage doubling rectifier diodes converted voltage. In the transducer as a T1 use a set of high-frequency transformer brand EL33-ASH from the power supply "obsolete" Canon printer BJC-2000. After measuring the resistance of the windings relative to each other it turned out what is their ratio (I to II) is 1:20.
The dissipation in the primary coil is made exactly from its middle (i.e. in this coil this case consists of two halves). Because transformers type EL33-ASH from old PSU printers I've accumulated a few, I took apart one of them, and can say that its the secondary winding consists of 220 turns wire diameter of 0.3 mm.
Battery lantern with a Converter
Fixed resistors R1 and R2 set to the width of the pulses at the output of the Converter. The scheme can be simplified (and not to use R1, R2), 4-th output DA1 need connect the common wire (minus the power).
Resistor R3 (together with the capacitor C1) specifies the operating frequency, which can to adjust to a slight extent: when you decrease the resistance of the resistor R1 oscillator frequency Converter increases; increasing the capacity capacitor C1 is the frequency decreases, and Vice versa.
About the details. Chip TL494 can be replaced by EU is entirely analogous. The power MOS-field-effect transistors VT1, VТ2 characterized by a small time switch and a simple control scheme. You can change them to IRFZ46N, IRFZ48N (the higher figure in the labeling, the more powerful analog current).
The electrical circuit of the voltage Converter 150 - 6 In
Instead of pulse rectifier diodes HER307 suitable HER304 - HER306 or CD with any letter index.
Oxide high-voltage capacitors C3 and C4 with a working voltage of at least 200 In - class CH, Carhop, NSO СD11GН, АSН-ЕLВ043.
Transmitter power is supplied from the portable battery a voltage of 6 V and a capacity of 1.2 Ah.
Protection of circuits against overload and reverse power (when using ready boards in other structures) can be implemented via a fuse and a diode, included in the forward direction at the entrance.
Author: A. Kashkarov