Basic Electronics
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Basic Electronics Basic Electronics

Training Objectives Provide knowledge / basic understanding of electronics concepts Familiarize / provide definitions of key terminology

Voltage (V) = Resistance (Ohms) X Current (Amps) V=RXI

Hydraulics vs. Electronics Hydraulic System Electrical System Hose & Tubing Board traces & wires Check valves Note: Reference pages 5-6 in “Your Guide to the Electronic Control of Fluid Power

Equivalent Hydraulic circuit

Switch-to-Battery Switch-to-Ground Analog Freque

Switch on battery side of load

Switch on Ground side of load

Analog Also known as a/d, analog to digital, voltage to digital Provides controller with a voltage – Voltage is between 0 to the defined upper voltage range (example 0 – 5 VDC) – Steps are based on resolution Resolutions – 8 bit, range is from 0 – 255 – 10 bit, range is from 0 – 1023 – 12 bit, range is from 0 – 4095 Common use: joysticks, foot pedals,

Common analog input Output ranges can vary Example: 10% joystick (supplied with 5VDC) – Center is 2.5VDC – Maximum output is 3VDC – Minimum output is 2

The number pulses per second Frequency = 1/period Example: If tperiod = 0.001 sec Frequency = 1/0.001 = 1000 Hz Units is in Hz (cycles per second) Examples – Engine speeds – Drum count – Water f

Resistive to Digital Resistance Temperature Detector Controller measure change in resistance of sensor Example ranges 0-250 Ohms or 0-4,000 Ohms Used: – Engine temperature sensors – Fuel gauge

Sinking Sourcing Analog PWM Digi

Sourcing Output Controller connects the customer output device to battery

Sinking Output Controller connects the customer output device to ground

Varying the “ON” time will result in a higher Vdc Duty cycle is the percentage on over the full period Duty cycle = (ton)/(tperiod)x100

Is a simple on or off output. Can be sourcing or sinking If On and sourcing, supplying battery from the controller

Allows for controlling a motor/valve in two direction (bi-direction) Eg: H-bridge Battery + + Motor Switch 4 Switch 2

Other terms Debounce time Frequency gauges Resistance gauges Numbering Systems Truth tables Microcontroller

Debounce Time The amount of time required for a mechanical switch to settle in the on/off state Debounce ON Debounce OFF

Frequency gauges Driven by Sinking or Sourcing Sinking need to add a pull-up resistor between the gauge and output. Sourcing built in resister in gauge. Higher the frequency of the output, the higher the needle will rise Pull-up resistor to battery HED Sinking Output Gauge

Resistance gauges Typically driven by supplying a current across a varying resistor sensor (eg: RTD sensor) HED drives it by varying the duty cycle, which in returns looks like the resistance is varying. Can only be driven by sinking outputs Variable Resistant load or HED sinking output

Numbering Systems Decimal = base 10 Binary = base 2 Hex = base 16

What is sent down the CAN bus Example: 1001 = 9 2 Single digit is called a bit 4 bits equal a nibble – Nibble

Base is 16 Example: 7F2 = 2034 4 bits is a hex digit 16 2 hex digits are a byte (or 8 bits binary) – 1111 11112 = FF16 = byte 4 hex digits or 2 bytes is a word – FF FF16 = w

Number Chart

Truth tables A truth table tells the output response based on the table’s inputs. Example: J1939 Msg from Engine stoppe d Warning indicator lamp Left turn signal Right turn signal Engine indicator lamp Beacon light output Left indicator lamp Right indicator lamp

Newer processors have them built in – Up to five controllers = 5 CAN port If not built in – Dependant on the real estate room on the board – And memory need to store the CAN messa

Flash – Application code is stored – Saves the information even if powered off RAM (read access memory) – Stores data during process (counters, timers, variables) – Lose when powered off EEPROM – Stores data usually changed during set-up – Has limit the number of times it can be w

Training Objectives Provide knowledge / basic understanding of electronics concepts Familiarize / provide definitions of key terminology