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PCB Drilling Machine (3)

PCB construction

The controller board contains all the electronics for the plate motor and four drill arms. As a matter of course, the board population is in accordance with the actual number of drill arms you have in use.All the components of the circuit can be built onto a single-sided printed circuit board. The PCB and component layout are shown in Figure 1. The power supply (as far as the transformers) is also built onto the circuit board: it provides a +30 V supply for the solenoids and stepper motor drivers, +15 V for the drill motors, and +5 V for the logic, regulated by IC1. The layout is very straightforward: along one long edge of the board we have the stepper motor drivers, each with a pair of terminal posts (K11-K20) for connection to the stepper motor windings. Since comparatively high currents flow through the ICs, they should be soldered directly to the board without sockets.
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Basic version, w/o tool arm
R1,R2,R41,R43,R44 = 10kOhm
R11,R14 = 1kOhm
R12,R15 = 1Ohm , 1W
R13,R16 = 56kOhm
R42 = 220Ohm
R45,R46,R47 = 560Ohm
R48 = 8-way resistor array 47kOhm
R49 = 1kOhm 5
C1,C2,C60,C61,C65 = 100nF, 5mm lead pitch
C3,C4,C5 = 3300µ F 50V radial
C22,C25,C26,C29 = 100nF, 2.5mm lead pitch
C23,C27 = 820pF, 2.5mm lead pitch
C24,C28 = 820pF, 5mm lead pitch
C63,C64 = 15pF
B1,B2 = GBU6B
D12 = LED, red, 3 mm dia.
IC1 = 7805
IC2 = GAL 16R8 (programmed, order code 010024-31)
IC3,IC4 = PBL3717A
IC13 = PIC16C64-20P (programmed, order code 010024-41)
IC14 = 74HC165
K1,K2 = 2-way PCB terminal block, lead pitch 5mm
K11,K12 = 2-way pinheader, 0.1in. lead pitch
K21 = 25-way sub-D plug, angled pins, PCB mount
F1,F2 = fuse, 2A (T) time lag with PCB mount holder and cap
BU1-BU4,BO1-BO4,JP1 = 2-way SIL pinheader
JP2 = jumper
X1 = 20MHz quartz crystal
PCB, order code 010024-1

(external components)
1 mains transformer for 2 drill arms: toroidal 2 x 12V 80VA
T9,T10,T11 = SFH309-F4 or LTR4206E
Stepper motors type KH2JM2-851

(for Tool Arm #1, replicate for other arms)
R8,R10 = 100Ohm
R17,R20 = 1kOhm
R18,R21 = 1Ohm , 1W
R19,R22 = 56kOhm
C16,C20 = 100nF, 5mm lead pitch
C30,C33,C34,C37 = 100n, 2.5mm lead pitch
C17,C21 = 220nF, 5mm lead pitch
C31,C35 = 820pF, 2.5mm lead pitch
C32,C36 = 820pF, 5mm lead pitch
D6,D8 = BUV27-200
T6,T8 = BUZ11
IC5,IC6 = PBL3717A
K8,K10 = 2-way pinheader, lead pitch 3.96mm
K13,K14 = 2-way pinheader, lead pitch 2.54mm
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