Knowledge of electronic environments DTG 6-8
Achievement Standard 1.47, AS91077
Knowledge of electronic environments focuses on the concepts and operational function of components that underpin the understanding of how electronic environments (functional combinations of hardware and embedded software in the real world, i.e. circuits, prototypes or products) are developed, assembled and tested.
Learning objective: DTG 6-8
Students will:
- demonstrate understanding of basic concepts and components in electronic environments.
Indicators
Students can:
- analyse basic concepts of electronics to explain the behaviour of electronic systems
- discuss the operational function of electronic components in a practical context.
Progression
As part of a junior technology and/or science programme students should learn some fundamental skills and knowledge related to electronics. Any opportunity to physically build real battery powered electric circuits where students are putting together wires, lights/LEDs, batteries, switches, motors, buzzers, solenoids, cells, or reusing circuits e.g. from electronic birthday cards. These will support early understandings with the terms open/closed, short circuit, voltage across, current through. All these concepts are better learned in real physical contexts.
At level 6 the emphasis should be on students building sound conceptual understandings of basic electronics. This can be achieved through a progression of practical exercises that are reinforced with complementary electronic theory lessons. Introduce as few concepts and components as possible at any one time and give students ample opportunity to come to full understanding.
Students should begin with building very simple single loop analogue circuits where they can focus on component recognition and accurate reading of component values. They should see that the circuit has a purpose and learn how each component contributes to the circuits overall function. They should describe this in terms of the circuit parameters of voltage as an energy level and current as a rate of flow of charge, and construction in terms of polarity, series/parallel, input/transformation process/output, and a circuit as a complete path. While students will initially build circuits from layout drawings they should also be learning about schematics at the same time and that schematics are the accepted way to define physical circuits; students then should quickly transition to building simple circuits from schematics rather than layout drawings. Understanding resistance is of primary importance and should lead into the voltage divider, which is a crucial conceptual understanding. Students need this understanding and how it relates to elementary circuit understandings in input subsystems. Analogue sensors (temperature or light) as part of voltage divider subsystems will need to be understood.
After this, students can progress to digital or binary understandings in terms of microcontroller programming and that voltage levels represent either a 1 or 0 (high or low). Multiple basic output devices can be introduced and the concepts of sequence, selection, and iteration control structures, as part of programming should be reinforced. This can be followed up by input circuits using switches and the concepts of single conditional (IF) statements to test inputs.
The Teacher Guidance section provides information that supports teachers scaffolding of learning from levels 1-8 of the curriculum. This allows for differentiation of a programme of learning.
The deliberate use of provide, guide, and support in this section signals that as students' capacity for self-management increases, teachers progressively reduce the level of scaffolding provided.
- Provide – the teacher should take full responsibility for introducing and explicitly teaching new knowledge, skills or practices.
- Guide – the students have a level of understanding and competency on which they can draw but the teacher remains primarily responsible for continuing to develop these.
- Support – the students take primary responsibility for their own learning, drawing on all their previous experiences to consolidate and extend their understanding. The teacher is supportive rather than directive.
- The Teacher Guidance also uses the term ensure to indicate when the teacher plays a monitoring role to check that conditions critical for learning are present.
Teacher guidance
To support students to develop understandings about basic concepts and components in electronic environments at level 6, teachers could:
- Provide the opportunity for students to learn about basic concepts through practical settings, for example, test conductors, insulators and semiconductor diode using a multimeter (ohms) or a light bulb and battery or learn why a circuit must be complete by identifying hidden breaks in a circuit using a multimeter.
- Guide students to identify basic components and their symbols. Support students to experiment with basic components in simple circuits to consolidate their understanding.
- Guide students to classify a provided selection of components in a tray as sensors, actuators or processors.
- Provide opportunity for discussion about the components properties in terms of energy transfer, for example, an LDR converting light to electrical energy and an LED converting electrical energy to light.
- Support students to use symbols to create schematics for simple circuits, such as a simple microcontroller circuit with at least one input and a few simple outputs.
- Provide a range of practical experiences, for example: exploring the properties of series and parallel connections using LEDs in a circuit; using a multimeter in a simple LED-resistor circuit to introduce the concept of voltage as an energy level, and the concepts of current and resistance.
- Provide opportunity for students to program a simple microcontroller to perform basic functions such as blinking LEDs controlled by a single switch. Students will be provided with the basic program structures for this.
- Guide students to examine simple two-loop circuits, including those with a microcontroller to identify and describe voltage divider and transistor switch subsystems in these.
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Contexts for teaching and learning
In electronics there is a significant opportunity to use practical contexts prior to theory, which provides students with significant motivation to learn. At this first stage of learning a sequence of mini-projects can be powerfully used to scaffold the understandings that students need as well as provide ample opportunity for repetition to reinforce understanding. Mini-projects can keep students focused in their learning and also encourage the development of motivation and self-management through repeated success.
An initial breadboard circuit using a battery, a switch, wire links, resistors, and an LED will help students develop conceptual understandings such as open/closed circuits, series/parallel circuits, polarity, basic specifications for component, as well as voltage and current. Students can be introduced to the conceptual understandings required in linking schematics to actual components. Understandings can be developed through a set of exercises including component recognition, accurate reading of component values, proficiency in component handling, and using a mulitmeter to measure voltage and current.
A temperature (thermistor)/darkness (LDR) detector circuit using a single MOSFET transistor (for example, 2N7000) or a BJT transistor (for example, BC337) with a small range of output devices (for example, LED, buzzer, small dc vibra-motor) gives students the opportunity to develop sound understandings of voltage dividers and input / transformation process/output subsystems as well as interpreting schematics.
Students would then move on to develop a range of microcontroller based mini-projects. With programming of microcontrollers a number of stages of understanding would need to be built up progressively. Initially multiple LED outputs could be controlled to produce a Knightrider like pattern and support student’s understanding of the sequential nature of computer programs. Next switches or other binary input devices as input subsystems would be used and students would learn about reading inputs and testing these using simple Boolean Logic to control different LED patterns. Mini-projects such as a moisture meter, motion detector, dice and countdown timer (using LEDs and/or 7-segment display) will support a basic understanding of variables. At this level students do not need to progress beyond two or three switch/binary input devices and two or three output devices with their microcontroller. Whereas too few I/O devices will hinder students’ abilities to generalise the concepts that they need to learn, too many may confuse them. Learning can be reinforced by reference to real electronic devices, which have simple electronic control and readily identifiable I/O e.g. a washing machine in terms of its I/O features, traffic lights in terms of multiple sensors and multiple outputs.
Students are required to use their workshop environment and equipment in a safe and correct manner at all times. Teachers should refer to the relevant sections in Safety in Technology Education: A Guidance Manual for New Zealand Schools.
Literacy considerations
Students need ongoing support to develop accurate language around component names and symbols. They need to use voltage and current (but not power) correctly and know basic specifications/parameters for usual components they will encounter (for example, LEDs, microcontrollers, batteries). With a simple circuit (for example, battery, switch, LED and current limit resistor) students should be learning to express circuit potentials around the circuit using voltage and current concepts correctly. These literacy skills are essential for their progression in electronics at later stages.
Systems concepts should be reinforced frequently and students should become comfortable with describing the function of input and output subsystems as collections of components to perform a specific role. Students should especially be familiar with the voltage divider as a commonly used input subsystem and the LED and current limiting resistor combinations as an output subsystem. They will need to understand that most individual components do not function as subsystems but require ancillary components to function.
A highly important consideration for student literacy is the crucial conceptual understanding of schematics, layout diagrams and physical circuits as one and the same. Students must begin early on in their learning to see a schematic as a ‘map’ for a physical circuit and learn to refer to each diagram and the physical circuit interchangeably.
Students will need to be taught how to use standard communication methods for their work, this includes such things as learning to draw system block diagrams, or how to use CAD programs to draw electronic circuits and layout diagrams.
Generic understanding of the academic terms
- To describe is a statement that gives details about the outcome or idea.
- To explain is to describe in detail with reasons – often including the how and why.
- To discuss requires an explanation that is comprehensive, detailed, broad and show evidence of some complexity in thinking. It may be a reasoned argument presenting a particular point of view, or a comparison and contrast between two ideas or concepts; or it may be a detailed reasoning and relationship between several complex ideas.
For assessment purposes a range of authentic assessment methods are appropriate including: classroom observation, teacher conferencing, practical work, peer discussions. Assignments, tests, and quizzes can also be relevant.
Resources to support teaching and learning
Other resources
Websites and textbooks exist to support basic electronics understandings - such as
http://www.falstad.com/circuit/. Also some electronics magazines regularly provide basic electronic learning courses (e.g. Everyday practical Electronics and Silicon Chip). When identifying a resource for novice learners it needs to be critiqued in light of its intended audience as often these resources are aimed at advancing students more quickly than is required at level 6. Careful selection rather than blanket use is recommended.
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Assessment for qualifications
The following achievement standard(s) could assess learning outcomes from this learning objective:
- AS91077 Digital Technologies 1.47: Demonstrate understanding of basic concepts used in the design and construction of electronic environments
Key messages from the standard
Students will need to demonstrate understanding by describing the operation of common components and a range of basic concepts to meet the assessment criteria. The concepts demonstrated must be contextualised within an electronic environment and demonstrated during the students own practice not for instance as part of isolated component research tasks. Students should be able to correctly build a basic circuit (incorporating a microcontroller), and describe each component’s contribution to the circuit.
The step-up to merit requires students to explain in more detail what is happening in the basic circuit (incorporating a microcontroller), and what some of the components are doing to assist the function of the overall circuit. Most of these concepts should be accurate and not confused.
The step-up to excellence requires students to discuss the functioning of components within their circuit giving examples of what impacts alternative values/component types might have on the overall operation of the circuit.
For the most up to date information, teachers should be referring to the latest version of the standards, conditions of assessment and assessment resources on TKI and the moderators reports, clarifications documents and student exemplars on the NZQA website. See links below.
Resources to support student achievement
Last updated November 7, 2022
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