Schematic Rise

Tuesday, September 2, 2014

Line Follower Robot Sensor Concept

Line Follower Robot Sensor Concept - Sensor line detector is used in line follower robot is usually based on the principle of light reflectionto distinguish the line with the background color. In the dark color of the light absorption is greater than that of white light reflected to the sensor becomes smaller.

Position sensor to track the trajectory and the example circuit.

Line Follower Robot Sensor Concept

Light used for the introduction of the line is usually visible light and infra-red. Sensors for visible light are commonly used are LDR (Light Depending Resistance), while for the infrared light is atransistor and photo diode (photodiode). Sensors placed at the bottom of the frame to hang the robot, so that its position can be located just above the track to be read.

Digital Thermometer with data processing of a microcontroller AT89C4051

Digital Thermometer 0-100.0°C is a digital thermometer that operates in modetemperature measurement in Celsius (° C). Digital Thermometer 0-100.0 ° C in this article uses data processor in the form of a microcontroller AT89C4051.

Temperature sensors used in Digital Thermometer 0-100.0 ° C. This temperature sensor LM35D. Digital Thermometer 0-100.0 ° C. It uses the temperature measurement data viewer in the form of 1 line LCD viewer. Digital Thermometer 0-100.0 ° C. It can display the temperature measurement data with a resolution of 0.1 ° C.

Digital Thermometer Circuit Diagram

Digital Thermometer 0-100.0 ° C. These temperature sensors make use of LM35D as temperature sensing. In Digital Thermometer 0-100.0 ° C. This temperature sensor measurement data this LM35D (Level Voltage) is then converted into 4-bit binary data using the ADC CA3162.

Then the 4-bit data from ADC CA3162 which is a measurement of data if the temperature is in the AT89C4951 microcontroller so that it becomes an operating principle of temperature measurement based on digital thermometers. In the final stage of the Digital Thermometer 0-100.0 ° C. This is the appearance of digital data temperature measurement, using digital data viewer of the LCD 1 line.

Extension for LiPo Charger Wiring diagram Schematic

Extension for LiPo Charger Project Image

The ‘Simple LiPo Charger’ published in Elektor Electronics April 2005 is a small and handy schema that allows you to quickly charge two or three LiPo cells. Especially in the model construction world are LiPo batteries used a lot these days, particularly model aeroplanes.

It is usual to use a series connection of three cells with these models. Since working with these model aeroplanes usually happens in the field, it would be nice if the batteries could be charged from a car battery.

We therefore designed a voltage converter for the LiPo charger concerned, which makes it possible to charge three cells in series. The voltage per cell increases while charging to a value of about 4.2 V, which gives a total voltage of 12.6 V. The converter, therefore, raises the 12-V voltage from the car battery to 16.5 V, from which the LiPo charger can be powered.

Extension for LiPo Charger Circuit Diagram

Extension-for-LiPo-Charger-Circuit-Diagram

A step-up controller type MAX1771 in combination with an external FET carries out the voltage conversion. The IC operates at a moderately high switching frequency of up to 300 kHz, which means that quite a small coil can be used.

Because the IC uses pulse frequency modulation (PFM) it combines the advantages of pulse width modulation (high efficiency at high load) with very low internal current consumption (110µA).

The IC is configured here in the so-called non-bootstrapped mode, which means that it is powered from the input voltage (12 V). The output voltage is adjusted with voltage divider R2/R3. This can be set to any required value, provided that the output voltage is greater than the input voltage.

Extension for LiPo Charger PCB Layout

Finally, sense resistor R1 determines the maximum output current that the schema can deliver. With the 25 mΩvalue as indicated, this is 2.5 A.

COMPONENTS LIST:
Resistors:
R1 = 25mΩ(e.g., Digikey # 2FR025-ND)
R2 = 100kΩ
R3 = 10kΩ
Capacitors:
C1,C4,C8 = 100nF
C2,C3 = 47µF 25V radial
C5,C7 = 100µF 25V radial
C6 = 100pF
Semiconductors:
D1 = 31DQ05 (e.g., Digikey #31DQ05-ND)
IC1 = MAX1771-CPA (e.g., Digikey #MAX1771EPA-ND)
T1 = IRFU3708 (e.g., Digikey #IRFU3708-ND)
Miscellaneous:
K1,K2 = 2-way PCB terminal block,lead pitch 5mm
L1 = 47µH high current suppressor
coil, (e.g, Digikey # M9889-ND)
PCB.,ref. 054012-1 from The PCBShop

Author : Unknown - Copyright : Elektor

Monday, September 1, 2014

Switching Mode Power Supply using STR

Switching Power supply circuit produces a voltage B + (dc voltage) needed television series taken from the net voltage household. G7 G7A chassis and power supply circuit using cool / cold in which the primary and the secondary power supply electrically separated so that the chassis can be directly connected to another device via an audio video terminal.

Switching power supply

This power supply circuit is a type SMPS (Switching Mode Power Supply) using mosfet transistor integrated circuit voltage controller in one IC package, namely STR-W6654. This IC will control the duty cycle of time off Vth2 Mosfet transistor to control the output voltage. Besides, the IC is also equipped with a safety circuit against overvoltage (OVP), overcurrent (OCP) and over temperature (TSD) circuit is working on 220V ac voltage with the input ac voltage range of 176V to 260V ac or known by the Wide range Regulators.

How to Work Series

Initial bias voltage dc pin6 IC801 obtained from an ac voltage through D811 and R817, in the beginning of this pin6 high input impedance, or simply need a current of about 100uA, if the voltage has reached the 10V, the IC will mendrive Mosfet transistor into On and transformer will generate stress induction through V1 , R819 and D816 making this pin6 voltage rises to 16V working voltage, and at this point impedance pin6 will shrink or current will increase to 30mA.

Voltage Stabilizer

Stabilizing the output voltage of the circuit is done by regulating the length of time off of the transistor current MOSFETs by using the feedback coupler photo released by the D807. And the D807 is controlled by the IC regulator IC802, IC is working based on the transformer secondary winding S2 (main output). Change IC802 PIN1 perceived stress will be informed on the photo coupler D807 and forwarded to the IC801 for correction.

Safety Over Voltage

In the event of errors / defects in the feedback path, the output voltage will rise out of control, but the series / IC801 has been equipped with a safety overvoltage, where pin6 IC801 can serve as a detection voltage, output voltage rises when the voltage V1 uncontrolled transformer also rises and via the R819, D816 IC801 pin voltage also rose, When the voltage reaches 34V in IC801 oscillator will stop / off switch and voltage pin6 will go down, and when the voltage reaches 7.5 V IC is going back to work and pin6 voltage rises again, if it again reaches 34V IC will die, so planes demikiian will be dead-alive, dead-alive.

Safety Flow / Cost More

The series is able to secure the power supply circuit to the flow or more load by detecting current flowing in the drain-source transistors MOSFETs. By placing a resistor R809, R835, and R811 on pin3 (source) and connected to pin7 (OCP), the more current or voltage drop on this resistor can be directly detected by a safety circuit overcurrent (OCP). In the event of overload or over current IC will stop for pin 6 voltage above 7.5V

Safety Over Temperature

IC STR-W6654 is also equipped with over temperature safety circuit (TSD). If an error occurs in the IC cooling load or metal, can cause uncontrolled temperature rise IC if IC exceeds 140 degrees then it will stop. The aircraft can live again when the voltage is below 7.5V pin6 (main switch is turned off) and the temperature has dropped below 140 degrees.

Stand-By Condition

With working characteristics pin6 tapped IC STR-W6654 especially voltage Latch Circuit Release Voltage (7.5V) the IC can be made to work on a very small load conditions (stand-by)

How it works series Stand-By

In normal conditions PIN1 UOC IC output is 5V (high) and on stand-by condition 0V (low). If the output of PIN1 UOC Low, Q852 off, Q857 is on, thus the input voltage to 10V PIN2 of IC 802 that will cause the output voltage to 52 volts IC801 PIN1. Thats due to the influence of input voltage PIN1 decreased from 26 V to 10V. so that the circuit feed back will inform you as there is more current. IC 801 IC801 stop temporarily until voltage falls below 7.5V pin6. After reaching 7.5V IC801 automatically revived. So this event will be repeated with certain intervals. The fall in line with all automatic 90V secondary circuit also fell, including PIN1 (V1) transformer. If the transformer voltage drop V1 also fell tentunnya pin6 IC801, IC801 will follow the working characteristics pin6.

Build a CW Signal Processor Wiring diagram Schematic

How to Build a CW Signal Processor Circuit Diagram? That is a good question but i explain this way. This schema provides interferenced rejection for the CW operator. The 567 phase-locked loop is configured to respond to tones from 500 to 1100 Hz. The Schmitt trigger reduces the weighting effect caused by the output of the PLL remaining low after removal of the audio signal.

Ten to 15 millivolts of audio activate the schema. For periods of loss of signal, schema B will automatically switch back to live receiver audio after a suitable delay. (If a relay with a 5-volt coil is not available, the schema can also be powered from +12 volts) When schema B is used, the contacts on relay K1 replace SI.

CW Signal Processor Circuit Diagram

Simple Schmitt Trigger Wiring diagram Schematic

This is a Simple Schmitt Trigger Circuit Diagram. Schmitt trigger is a comparator schema with hysteresis, implemented by applying positive feedback to the non-inverting input of a comparator. In this schema By replacing the common-emitter resistor in a conventional Schmitt by a zener diode the hysteresis normally associated with these diagram is eliminated.

Simple Schmitt Trigger Circuit Diagram

Low Loss Step Down Converter

This schema arose from the need of the author to provide a 5 V output from the 24 V battery of a solar powered genera-tor. Although solar power is essentially free it is important not to be wasteful especially for small installations; if the battery runs flat at midnight you’ve got a long wait before the sun comes up again. The basic requirement was to make an efficient step-down converter to power low voltage equipment; the final design shown here accepts a wide input voltage from 9 to 60 V with an output current of 500 mA. The efficiency is very good even with a load of 1 mA the design is still better than a standard linear regulator. The low quiescent current (200 µA) also plays a part in reducing losses.

Some of the components specified (particularly the power MOSFET) are not the most economical on the market but they have been deliberately selected with efficiency in mind.

Low Loss Step Down Converter Circuit Diagram

When power is applied to the schema a reference voltage is produced on one side of R2. D1 connects this to the sup-ply (pin 7) of IC1 to provide power at start-up. Once the schema begins switching and the output voltage rises to 5 V, D2 becomes forward biased and powers the IC from the output. Diode D1 becomes reverse biased reducing current through R1. When the schema is first powered up the voltage on pin 2 of IC1 is below the reference voltage on pin 3, this produces a high level on output pin 6. The low power MOSFET T1 is switched on which in turn switches the power MOSFET T3 via R5 and the speed-up capacitor C4, the output volt-age starts to rise.

When the output approaches 5 V the voltage fed back to the inverting input of IC1 becomes positive with respect to the non inverting input (reference) and switches the output of IC1 low. T1 and T3 now switch off and C3 transfers this negative going edge to the base of T2 which conducts and effectively shorts out the gate capacitance of T3 thereby improving its switch off time.

The switching frequency is not governed by a fixed clock signal but instead by the load current; with no load attached the schema oscillates at about 40 Hz while at 500 mA it runs at approximately 5 kHz. The variable clock rate dictates that the output inductor L1 needs to have the relatively high value of 100 mH. The coil can be wound on ferrite core material with a high AL value to allow the smallest number of turns and produce the lowest possible resistance. Ready-made coils of this value often have a resistance greater than 1 ? and these would only be suitable for an output load current of less than 100 mA.

The voltage divider ratio formed by R4 and R3 sets the output voltage and these values can be changed if a different out-put voltage is required. The output volt-age must be a minimum of 1 V below the input voltage and the output has a minimum value of 4 V because of the supply to IC1.

A maximum efficiency of around 90 % was achieved with this schema using an input voltage between 9 and 15 V and supplying a current greater than 5 mA, even with an input voltage of 30 V the schema efficiency was around 80 %. If the schema is used with a relatively low input voltage efficiency gains can be made by replacing D4 with a similar device with a lower reverse breakdown voltage rating, these devices tend to have a smaller for-ward voltage drop which reduces losses in the diode at high currents. At higher input voltage levels the value of resistor R1 can be increased proportionally to reduce the quiescent current even further.