1. The Schematic View

The circuit Schematic shall be included in the PCB assembly drawing. This shall include the following:-

1. The circuit diagram.

2. The connector pin numbering and functions.

3. Where a mechanical movement or contact system influences inputs or outputs of the circuit, such mechanical features should be represented in the schematic to aid understanding.

4. Passive component values shall be shown on the schematic.

5. Semiconductor part numbers.

6. All components will be identified by a designator that shall be referred to in the bill of materials and PCB assembly drawings. Refer to the table below for the prefixes to be used for each component type.

Resistor	R
Capacitor	C
Diode	D
Transistor	Q
IC	U
LED	LED
Inductor	L
Connector	CON
Crystal	X
Switch	SW

7. Components shown on the schematic but not fitted must be identified by drawing a broken line box around the component. There should be text adjacent to the box “NOT FITTED”. Alternatively, the component may be crossed out on the schematic, and a note reading “CROSSED OUT COMPONENTS IN THE SCHEMATIC VIEW ARE NOT TO BE FITTED” shall be included. The best way to denote this shall be chosen according to the complexity of the schematic and the grouping of the components in question, in such a way as maintain clarity and avoid clutter in the schematic.

8. Signals and terminal names required to improve understanding in other documents and software should also be shown in the schematic.

9. For simplicity the schematic may be drawn in blocks with off page connectors.

10. The schematic may be spread over several sheets if necessary for clarity.

2. Bill Of Materials

The Bill Of Materials (BOM) Table must identify all electronic components and their description in an unambiguous way. The component reference designators used in the BOM must be consistent with those shown in the Schematic View. All components shown in the schematic view have to be listed in the BOM. Those which are not to be mounted should be placed in separate lines and have an entry of ‘0’ in the ‘Quantity’ column (see Table 1).

The table shall have the following format: -

BILL OF MATERIALS TABLE 1
REF. DES.	QTY	DESCRIPTION	PACKAGE	PREFERRED SUPPLIER	ALT. SUPPLIER	PART NOS
R1	1	RESISTOR 270Ω 1% - 0.25W	1206	VISHAY	PHICOMP	CRCW-1206-270F-100-RT6
R2	0	NOT FITTED	1206	N/A	N/A	N/A
C1,C2	2	CERAMIC CAPACITOR 20%, 10nF, 50V	0603	PANASONIC	VISHAY	ECJ1VB1H103M