--- azemark: 2 title: AzeMark circuit schematics author: - AzeForge examples x-circuit-symbol-convention: iec --- # Circuit schematics Circuit blocks describe analog and digital schematics without coordinates: components, named nodes, and terminal bindings carry the topology, and the renderer resolves the wires. Every file in this family fixes one symbol convention, here IEC, so the shapes of sources, gates, and flip-flops stay consistent across the examples. ## Analog schematics Analog sections bind passive elements, sources, and semiconductors to named nodes; a terminal that is never bound is a compile error, so each example closes every pin it declares. The simplest analog form is a resistive divider that taps a fixed fraction of the supply rail. :::: circuit id: divider-bias-network title: Resistive divider bias network ---- - kind: node ref: rail - kind: node ref: tap - kind: node ref: return role: reference label: 0 V return - kind: voltage-source ref: V1 value: 12 V mode: dc - kind: resistor ref: R1 value: 1 kohm - kind: resistor ref: R2 value: 2 kohm - kind: connect terminal: V1.positive node: rail - kind: connect terminal: V1.negative node: return - kind: connect terminal: R1.a node: rail - kind: connect terminal: R1.b node: tap - kind: connect terminal: R2.a node: tap - kind: connect terminal: R2.b node: return :::: Filtering is the same topology with a capacitor in place of the lower resistor, plus a voltage annotation that names the two nodes it spans. :::: circuit id: rc-lowpass-filter title: RC low-pass filter description: single pole RC filter with a labeled output ---- - kind: node ref: drive - kind: node ref: out - kind: node ref: return role: reference - kind: voltage-source ref: V1 value: 5 V mode: dc - kind: resistor ref: R1 value: 1 kohm - kind: capacitor ref: C1 value: 100 nF - kind: connect terminal: V1.positive node: drive - kind: connect terminal: V1.negative node: return - kind: connect terminal: R1.a node: drive - kind: connect terminal: R1.b node: out - kind: connect terminal: C1.a node: out - kind: connect terminal: C1.b node: return - kind: current-label terminal: R1.a direction: into - kind: voltage-label positive: out negative: return :::: The deepest analog form stages an amplifier with a dependent source: the op-amp senses a divided fraction of its own output, and a transresistance stage converts the sensed drive into a ground-referenced level across a load resistor. :::: circuit id: opamp-transresistance-stage title: Op-amp stage with a transresistance dependent source description: non-inverting amplifier buffering a CCVS stage flow: left-to-right ---- - kind: node ref: input - kind: node ref: feedback - kind: node ref: drive - kind: node ref: sense - kind: node ref: rail-positive - kind: node ref: rail-negative - kind: node ref: return role: reference - kind: voltage-source ref: V1 value: 5 V mode: dc - kind: voltage-source ref: V2 value: 15 V mode: dc - kind: voltage-source ref: V3 value: 15 V mode: dc - kind: resistor ref: R1 value: 10 kohm - kind: resistor ref: R2 value: 1 kohm - kind: resistor ref: R3 value: 220 ohm - kind: op-amp ref: U1 name: gain stage - kind: dependent-source ref: E1 value: 1 kohm mode: CCVS - kind: connect terminal: V1.positive node: input - kind: connect terminal: V1.negative node: return - kind: connect terminal: V2.positive node: rail-positive - kind: connect terminal: V2.negative node: return - kind: connect terminal: V3.positive node: rail-negative - kind: connect terminal: V3.negative node: return - kind: connect terminal: U1.nonInverting node: input - kind: connect terminal: U1.inverting node: feedback - kind: connect terminal: U1.output node: drive - kind: connect terminal: U1.positiveSupply node: rail-positive - kind: connect terminal: U1.negativeSupply node: rail-negative - kind: connect terminal: R1.a node: drive - kind: connect terminal: R1.b node: feedback - kind: connect terminal: R2.a node: feedback - kind: connect terminal: R2.b node: return - kind: connect terminal: E1.controlPositive node: drive - kind: connect terminal: E1.controlNegative node: return - kind: connect terminal: E1.positive node: sense - kind: connect terminal: E1.negative node: return - kind: connect terminal: R3.a node: sense - kind: connect terminal: R3.b node: return :::: ## Digital schematics Digital sections use the same node and terminal model: gates, multiplexers, flip-flops, and the digital input and output symbols that give a schematic its boundary pins. A two-level gate network shows how a shared intermediate node feeds a second stage. :::: circuit id: gate-network-sum title: Two-level gate network ---- - kind: node ref: a - kind: node ref: b - kind: node ref: c - kind: node ref: partial - kind: node ref: y - kind: digital-input ref: A name: A - kind: digital-input ref: B name: B - kind: digital-input ref: C name: C - kind: and ref: U1 inputs: 2 - kind: or ref: U2 inputs: 2 - kind: digital-output ref: Y name: Y - kind: connect terminal: A.out node: a - kind: connect terminal: B.out node: b - kind: connect terminal: C.out node: c - kind: connect terminal: U1.in1 node: a - kind: connect terminal: U1.in2 node: b - kind: connect terminal: U1.out node: partial - kind: connect terminal: U2.in1 node: partial - kind: connect terminal: U2.in2 node: c - kind: connect terminal: U2.out node: y - kind: connect terminal: Y.in node: y :::: A flip-flop stage adds a clocked element, with the data and clock nets shared between the boundary pins and the register. :::: circuit id: flipflop-capture-stage title: Clocked capture stage description: one D flip-flop between boundary pins ---- - kind: node ref: data-net - kind: node ref: clock-net - kind: node ref: q-net - kind: digital-input ref: D name: D - kind: digital-input ref: CLK name: CLK - kind: d-flip-flop ref: FF1 - kind: digital-output ref: Q name: Q - kind: connect terminal: D.out node: data-net - kind: connect terminal: CLK.out node: clock-net - kind: connect terminal: FF1.d node: data-net - kind: connect terminal: FF1.clk node: clock-net - kind: connect terminal: FF1.q node: q-net - kind: connect terminal: Q.in node: q-net :::: The full clocked chain pairs two registers with a multiplexer that selects among the registered value, the second register, and two external inputs. :::: circuit id: clocked-logic number: true title: Clocked logic acceptance circuit ---- - kind: node ref: din - kind: node ref: en - kind: node ref: clk - kind: node ref: u1-out - kind: node ref: ff1-q - kind: node ref: ff2-q - kind: node ref: d2 - kind: node ref: d3 - kind: node ref: s0 - kind: node ref: s1 - kind: node ref: sel - kind: digital-input ref: DIN name: DIN - kind: digital-input ref: EN name: EN - kind: digital-input ref: CLK name: CLK - kind: digital-input ref: D2 name: D2 - kind: digital-input ref: D3 name: D3 - kind: digital-input ref: S0 name: S0 - kind: digital-input ref: S1 name: S1 - kind: digital-output ref: SEL name: SEL - kind: and ref: U1 inputs: 2 - kind: d-flip-flop ref: FF1 - kind: d-flip-flop ref: FF2 - kind: mux-4to1 ref: M1 - kind: connect terminal: DIN.out node: din - kind: connect terminal: EN.out node: en - kind: connect terminal: CLK.out node: clk - kind: connect terminal: D2.out node: d2 - kind: connect terminal: D3.out node: d3 - kind: connect terminal: S0.out node: s0 - kind: connect terminal: S1.out node: s1 - kind: connect terminal: U1.in1 node: din - kind: connect terminal: U1.in2 node: en - kind: connect terminal: U1.out node: u1-out - kind: connect terminal: FF1.d node: u1-out - kind: connect terminal: FF1.clk node: clk - kind: connect terminal: FF1.q node: ff1-q - kind: connect terminal: FF2.d node: ff1-q - kind: connect terminal: FF2.clk node: clk - kind: connect terminal: FF2.q node: ff2-q - kind: connect terminal: M1.d0 node: ff1-q - kind: connect terminal: M1.d1 node: ff2-q - kind: connect terminal: M1.d2 node: d2 - kind: connect terminal: M1.d3 node: d3 - kind: connect terminal: M1.s0 node: s0 - kind: connect terminal: M1.s1 node: s1 - kind: connect terminal: M1.out node: sel - kind: connect terminal: SEL.in node: sel :::: ## Floating and disconnected Circuits A Circuit is a graph, not a netlist check: a schematic with no reference node still compiles, and two separate subcircuits in one block are legal. Those cases are reported as warnings so an author can see them without the compiler rejecting the drawing. A floating clocked circuit declares a spare node it never wires and omits any ground reference; the node is reported as unused while the block still compiles. :::: circuit id: floating-clock-circuit number: true title: Floating clocked logic circuit ---- - kind: node ref: din - kind: node ref: en - kind: node ref: clk - kind: node ref: u1-out - kind: node ref: ff1-q - kind: node ref: ff2-q - kind: node ref: d2 - kind: node ref: d3 - kind: node ref: s0 - kind: node ref: s1 - kind: node ref: sel - kind: node ref: spare label: intentionally unused - kind: digital-input ref: DIN name: DIN - kind: digital-input ref: EN name: EN - kind: digital-input ref: CLK name: CLK - kind: digital-input ref: D2 name: D2 - kind: digital-input ref: D3 name: D3 - kind: digital-input ref: S0 name: S0 - kind: digital-input ref: S1 name: S1 - kind: digital-output ref: SEL name: SEL - kind: and ref: U1 inputs: 2 - kind: d-flip-flop ref: FF1 - kind: d-flip-flop ref: FF2 - kind: mux-4to1 ref: M1 // bindings - kind: connect terminal: DIN.out node: din - kind: connect terminal: EN.out node: en - kind: connect terminal: CLK.out node: clk - kind: connect terminal: D2.out node: d2 - kind: connect terminal: D3.out node: d3 - kind: connect terminal: S0.out node: s0 - kind: connect terminal: S1.out node: s1 - kind: connect terminal: U1.in1 node: din - kind: connect terminal: U1.in2 node: en - kind: connect terminal: U1.out node: u1-out - kind: connect terminal: FF1.d node: u1-out - kind: connect terminal: FF1.clk node: clk - kind: connect terminal: FF1.q node: ff1-q - kind: connect terminal: FF2.d node: ff1-q - kind: connect terminal: FF2.clk node: clk - kind: connect terminal: FF2.q node: ff2-q - kind: connect terminal: M1.d0 node: ff1-q - kind: connect terminal: M1.d1 node: ff2-q - kind: connect terminal: M1.d2 node: d2 - kind: connect terminal: M1.d3 node: d3 - kind: connect terminal: M1.s0 node: s0 - kind: connect terminal: M1.s1 node: s1 - kind: connect terminal: M1.out node: sel - kind: connect terminal: SEL.in node: sel :::: Disconnected teaching schematics place two unrelated subcircuits side by side, with a spare node left over from an earlier revision; both warning conditions fire and nothing is reported as an error. :::: circuit id: disconnected-instructional number: true title: Disconnected instructional schematic with warnings ---- - kind: node ref: n1 - kind: node ref: n2 - kind: node ref: n3 - kind: node ref: n4 - kind: node ref: n5 - kind: node ref: n6 label: unused spare // First component-bearing subgraph: simple RC low-pass. - kind: voltage-source ref: V1 value: 5 V - kind: resistor ref: R1 value: 1 kohm - kind: capacitor ref: C1 value: 1 uF // Second component-bearing subgraph: LED with series resistor. - kind: voltage-source ref: V2 value: 3 V - kind: resistor ref: R2 value: 220 ohm - kind: led ref: LED1 - kind: connect terminal: V1.positive node: n1 - kind: connect terminal: V1.negative node: n2 - kind: connect terminal: R1.a node: n1 - kind: connect terminal: R1.b node: n3 - kind: connect terminal: C1.a node: n3 - kind: connect terminal: C1.b node: n2 - kind: connect terminal: V2.positive node: n4 - kind: connect terminal: V2.negative node: n5 - kind: connect terminal: R2.a node: n4 - kind: connect terminal: R2.b node: n5 - kind: connect terminal: LED1.anode node: n5 - kind: connect terminal: LED1.cathode node: n4 ::::