Showing posts with label car. Show all posts
Showing posts with label car. Show all posts
Wednesday, December 18, 2013
Car Cigar Lighter to USB Power Socket
Nowadays, almost all computer systems have logic blocks for working with a USB port. A USB port, in practice, is capable of supplying more than 100 mA of continuous electric current at 5V to the peripherals which are hooked up with the bus. So a USB port could be utilized, without having any problems, for powering 5V DC operated tiny electronic devices.
Today, a lot of handheld gadgets (for example, portable reading lamps) utilise this resource of the USB port to recharge their built-in battery pack using the support of an internal circuitry. Typically 5V DC, 100mA electric current is needed to satisfy the input electrical power demand. The above diagram shows the circuit of a versatile USB power socket that properly converts the 12V battery voltage into stable 5V. This circuit can make it possible to power / recharge any USB power-operated device, working with in-dash board cigar lighter socket of the car.
The DC supply presented from the cigar lighter socket is fed to an adjustable, three-pin regulator LM317L (IC1).
Capacitor C1 buffers any disorder in the input supply. Resistors R1 and R2 regulate the output of IC1 to constant 5V, that is accessible at the ‘A’ type female USB socket. Red LED1 signifies the output condition and zener diode ZD1 acts as a protector against excessive voltage. Assemble the circuit on a general purpose PCB and enclose inside a slim plastic cabinet as well as the indicator and USB socket. Whilst wiring the USB outlet, make sure proper polarity of the supply. For interconnection between the cigar plug pin as well as the device, use a long coil cord as shown in second image.
Source: http://www.ecircuitslab.com/2012/07/car-cigar-lighter-to-usb-power-socket.html
Thursday, March 28, 2013
Car Battery 12v Charger
The usual chargers of battery automotive, are simple and cheap appliances that charge continuously the battery, with a rythm of few amperes, for the time where the appliance is ON. If the holder do not close in time the charger, the battery will overcharge and her electrolytic faculty are lost with evaporation or likely exists destruction of her elements. The charger of circuit exceeds these faults. It checks electronic the situation of charge of battery and it has circuit of control with retroaction, that forces the battery charge with biggest rythm until charge completely.
Circuit diagram:
Car Battery 12v Charger Circuit Diaram
When charge completely, it turns on one RED led (LD2). The charger has been drawn in order to charge batteries of 12V, ONLY. What should watch it from what it manufactures the circuit, they are the cables that connect the transformer with the circuit and in the continuity the battery, should they are big cross-section, so that heat when it passes from in them the current of charge and also they do not cause fall of voltage at the way of current through them.
Adjustment
After assembling of the circuit, adjust TR1 to null value, power-up and make the following adjustments :-
- Without connecting the battery check that the 2 LED?s are turned on.
- Connect a car battery to the circuit and check that LD2 is OFF and a current (normally 2A to 4A) is flowing to the battery.
- Adjust TR1 until LD2 turns ON and the charge current is cut.
- Adjust TR1 to null value and charge the battery using the hydrometer technique (if you do not have or do not know how to use a hydrometer, then use a good condition battery and charge).
Carefully adjust TR1 so that LD2 begins to turn ON and the charge current falls to a few hundred milliamps (mA). If TR1 is set correctly then in the next round of charging you will noticed LD2 begin to flicker as the battery is being charged. When battery is completely charged, LD2 turns ON completely.TR1 does not need further adjustment anymore. Q1 is connected in line with the battery and is fired by R3, R4 and LD2. The R2, C1, TR1 and D2 sense the voltage of the battery terminal and activate Q2 when the voltage of the battery terminal exceeds the value predetermined by TR1.
When an uncharged battery is connected, the terminal voltage is low. Under this circumstance, Q2 is turned OFF and Q1 is fired in each half cycle by R3, R4 and LD2. The Q1 functions as a simple rectifier and charges the battery. If the battery terminal voltage is increased above the level that had been fixed by TR1, then Q2 shifts the control of Q1 gate. This deactivates Q1 and cuts off the current supply to the battery and turns LD2 ON indicating that the charge has been completed. Q1 and bridge rectifier GR1 should be mounted on heatsinks to prevent overheating. M1 is a 5A DC ammeter to measure the charge current.
Source :users.otenet.gr
Tuesday, March 26, 2013
18W Car Stereo Amplifier Rise
This automobile stereo amplifier project is a class AB audio power amplifier using the Hitachi HA13118 module. It not only can be used in automobile application but also in any transportable or home amplifier process. It is simple to construct & has a maximum of outside parts. The module has a high power output from a low voltage supply using the bridge tied load system, & a high gain of 55dB.
This project will be useful in applications where the input signal is a low level, without requiring the use of a separate pre-amplifier. This IC module has a built in surge protection circuit, thermal shutdown circuit, ground fault protection circuit & power supply fault protection circuit making it reliable.
This project will be useful in applications where the input signal is a low level, without requiring the use of a separate pre-amplifier. This IC module has a built in surge protection circuit, thermal shutdown circuit, ground fault protection circuit & power supply fault protection circuit making it reliable.
The Specifications of this project
D.C. Input : 8 – 18V at 1-2 A
Power output : 18W maximum, 4 ohm load, 18V DC supply
S/N ratio : > 70 dB
THD : < 0.2% @ 1W
Freq. Response : ~ 30 Hz to 30 kHz, –3 dB
Input level : < 25 mV, for full output (G > 50dB)
Input Impedance : ~ 30 k ohm
D.C. Input : 8 – 18V at 1-2 A
Power output : 18W maximum, 4 ohm load, 18V DC supply
S/N ratio : > 70 dB
THD : < 0.2% @ 1W
Freq. Response : ~ 30 Hz to 30 kHz, –3 dB
Input level : < 25 mV, for full output (G > 50dB)
Input Impedance : ~ 30 k ohm
The supply voltage necessary for this project is 8 -18V DC, at least one to two Amps. Maximum output power will only be obtained with a power supply of 18V at greater than two A, using a four ohm speaker. The power supply ought to be well filtered to reduce mains hum, a regulated supply will reduce noise even further. Additional filtering is unnecessary if operating from a battery supply.
Circuit Diagram Description
Most of the circuitry is contained within the amplifier module. C10 is the input coupling capacitor and blocks DC from the input. C11 bypasses any RF which may be present at the input. C1 & C2 provide an AC ground for the inverting inputs of the IC. R1/C7 and R2/C8 provide a high frequency load for stability with difficult speakers. C five & C six provide bootstrap feedback for the IC. C9 & C12 provide power supply filtering.
Most of the circuitry is contained within the amplifier module. C10 is the input coupling capacitor and blocks DC from the input. C11 bypasses any RF which may be present at the input. C1 & C2 provide an AC ground for the inverting inputs of the IC. R1/C7 and R2/C8 provide a high frequency load for stability with difficult speakers. C five & C six provide bootstrap feedback for the IC. C9 & C12 provide power supply filtering.
An externally mounted logarithmic potentiometer of between 10k ohm and 50k ohm, is used depending on the desired input impedance. The impedance ought to be keep as high as feasible for a guitar amp, unless using a separate pre-amp. Make sure-that the heat sink is mounted to the module.
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