85
Circuit 60:
DC-DC converter 9V to 35V with coil-moving instrument
Setup information
Install the two transistors, the diode and the four resistors as shown in
Fig. 2.60 followed by
the ceramic
capacitor, the electrolytic capacitor and the fixed value inductor. It is important to make sure that the elec-
trolytic capacitor has a dielectric strength of 160V. The thirteen jumper wires come next. Last but not least
connect the moving-coil instrument. Check the placement on the board again and only then connect the
battery.
Components required:
2 x 2N3904 transistors,
1 x 1N4148 silicon diode,
1 x 1 k
Ω
resistor, 1 x 10 k
Ω
resistor, 1 x 22 k
Ω
resistor,
1 x 100 k
Ω
resistor,
1 x 220 μH fixed induct-
ance, 1 x 1 nF ceramic
capacitor, 1 x 10 μF/160V
electrolytic capacitor,
1 x breadboard, 1 x 9V
battery with clip connector,
1 x moving-coil instrument
Fig. 2.60:
DC-DC converter 9V to
35V with coil-moving instrument
Experiment
This circuit is used to convert a larger DC voltage to a smaller one. The two transistors ensure that strong
current pulses are sent through the fixed value inductor. This results in a very high induction voltage, which
charges the electrolytic capacitor C2 after rectification with D1. There then the highly-transformed output
voltage is available. In our present circuitry the unregulated output voltage is at 35V. The voltage is detected
by the coil-moving instrument.
The circuit diagram for this experiment is shown in Chap. 3, Fig. 3.60.
Summary of Contents for ELECTRONICS EXPERIMENTS BOX
Page 4: ......
Page 265: ...267 Fig 3 56 Cir cuit 56 Audio limiter Fig 3 57 Circuit 57 Amplifier for a storm detector...
Page 269: ...271 Fig 3 64 Circuit 64 Stabilizer for 1 9 V Fig 3 65 Circuit 65 Stabilizer for 2 5 V...
Page 275: ...277 Fig 3 80 Circuit 80 Quiztimer 30 seconds Fig 3 81 Circuit 81 Handy diode tester...
Page 315: ...317 Fig 3 179 Circuit 179 HF generator 150 kHz Fig 3 180 Circuit 180 HF generator 420 kHz...
