Friday, August 9, 2013
Mobile Phone and iPod Battery Charger
Charge your iPod without connecting it to a computer!
Using the USB port on your computer to charge your player’s batteries is not always practical. What if you do not have a computer available at the time or if you do not want to power up a computer just for charging? Or what if you are traveling? Chargers for Mobile Phones iPods and MP3 players are available but they are expensive and you need separate models for charging at home and in the car.
This charger can be used virtually anywhere. While we call the unit a charger, it really is nothing more than a 5V supply that has a USB outlet. The actual charging circuit is incorporated within the iPOD or MP3 player itself, which only requires a 5V supply. As well as charging, this supply can run USB-powered accessories such as reading lights, fans and chargers, particularly for mobile phones.
The supply is housed in a small plastic case with a DC input socket at one end and a USB type "A" outlet at the other end, for connecting to Mobile Phone, an iPod or MP3 player when charging. A LED shows when power is available at the USB socket. Maximum current output is 660mA, more than adequate to run any USB-powered accessory.
Pictures, PCB and Circuit Diagram:
Front View Of Mobile Phone and iPod Battery Charger Circuit
Bottom View Of Mobile Phone and iPod Battery Charger Circuit
PCB Layout Of Mobile Phone and iPod Battery Charger Circuit
Mobile Phone and iPod Battery Charger Circuit Diagram
| Parts | Description |
| P1 | 1K |
| R1 | 1R-0.5W |
| R2 | 1R-0.5W |
| R3 | 1R-0.5W |
| R4 | 1K |
| R5 | 560R |
| R6 | 10R-0.5W |
| R7 | 470R |
| C1 | 470uF-25V |
| C2 | 100nF-63V |
| C3 | 470pF |
| C4 | 100uF-25V |
| D1 | 1N5404 |
| D2 | 1N4001 |
| D3 | 1N5819 |
| D4 | 5.1V-1W Zener Diode |
| D5 | 5mm. Red LED |
| L1 | 220uH |
| S1 | USB A Type Socket |
| SW1 | On/Off Switch |
| IC1 | MC34063A |
Specifications:
Output voltage ----------------------5V
Output current ---------------------660mA maximum for 5V out
Input voltage range ------------------9.5V to 15V DC
Input current requirement ----------500mA for 9V in, 350mA for >12V input
Input current with output shorted--- 120mA at 9V in, 80mA at 15V in
Output ripple ------------------------14mV (from no load to 660mA)
Load regulation ----------------------25mV (from no load to 660mA)
Line regulation ----------------------20mV change at full load from 9 to 18V input
No load input current ----------------20mA
(The specification for the computer USB 2.0 port requires the USB port to deliver up to 500mA at an output voltage between 5.25V and 4.375V).
The circuit is based around an MC34063 switch mode regulator. This has high efficiency so that there is very little heat produced inside the box, even when delivering its maximum output current. The circuit is more complicated than if we used a 7805 3-terminal regulator but since the input voltage could be 15V DC or more, the voltage dissipation in such a regulator could be 5W or more at 500mA. and 5W is far too much for a 7805, even with quite a large heatsink. Credit for this circuit goes to SiliconChip, A wonderful electronics magazine.
Source :www.extremecircuits.net
Tuesday, April 2, 2013
Automobile Head Light Dipper with Cell Phone Charger Circuit
The following brief explanation was provided by Miss Surya for getting a better view of the proposed circuit design of an automobile automatic dimmer cum dipper head light switch circuit with an optional cell phone charger circuit for facilitating the charging of a cell phone also on board.
Circuit Description
Here the IC 555 has been used not as a charging indicator rather as a comparator for controlling the dipping action of the head lamps.
The use if IC 555 as a charging indicator would have made the circuit unnecessarily complicated, therefore a novel and simpler way is selected for the charging ON indication.
The LED connected across the 5 Ohm watt current limiting resistor effectively indicates the charging status of the cell phone and switches OFF the moment the charging process stops.
The IC 555 works like a comprartor here, when light falls on the LDR, voltage at PIN#2 rises above the set internal threshold which prompts the IC to change its output PIN#3 voltage from 0 to 12, triggering the connected relay.
The relay contacts immediately transfer the positive supply from the "high" filament to the "low" filament of the head lamps, resulting in an instant dipping of the lamp intensity.
The LDR must be positioned in such a way that it only receives light rays coming from front of the vehicle, which will be mostly the lights from another vehicles head lamps.
