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USB DMX interface schematic

The schematic above is marked as revisino 1.2, but it is identical to the 1.3 revision with 1 excpetion. The is a 100R resistor on the RD & WR lines between IC2 & IC1. I will update the schematic as soon as I get a chance to reflect this.

The following table lists all the parts you need to make up a PCB without a case. I have also provided a potential supplier for each of the items, although in many cases there are many different suppliers who will be able to provide the same or compatble parts.

You can also order the PCB and programemd PIC, or a full kit of all the parts from the Ordering section.

Part Value Supplier Code
IC1 PIC16F874A-I/L Farnell 976-1195
Socket Farnell 1101356
Socket Farnell 110-3851
IC3 DS2016 Farnell 795-914
Socket Farnell 428-5645
IC4 NDP6020P Farnell 101-7724
IC5 NKE0505SC Farnell 115-8357
IC6, IC7 6N137 Farnell 999-4866
Socket Farnell 428-5566
IC8 MAX488CPA Farnell 972-5598
Socket Farnell 428-5566
R1, R2, R5 10K Farnell 934-2419
R3, R4 470R Farnell 934-3245
R6 - R9 22R Farnell 477-680
R10, R11 120R Farnell 770-024
R12, R13 100R Farnell 934-2397
R14 * 1K Farnell 934-2400
C1, C2 22pF Farnell 746-990
C3 - C7 100nF Farnell 121-6444
C8 - C9 * 100nF Farnell 121-6444
XTL1 HC49/4H 20Mhz Farnell 971-2879
D1 - D4 BZX85-C5V6 Farnell 984-4252
CON2 KK 22-27-2051 Farnell 973-1679
(Socket) KK 22-01-2055 Farnell 973-1679
(Crimp Terminals) KK 08-50-0106 Farnell 101-3097

* Required when using the UM245R conversion module

If you are going to use the suggested case, you must not put IC3 in a socket, and you will not need CON2. You can also use the cheaper socket type from IC3 on IC2 as there is no pressure from inserting the USB leads. The following table lists the additional parts that you will require.

Part Value Supplier Code
XLR Socket NC5FDM3H Canford 40-583
USB Socket NAUSB CPC CN09520
Endplate x 2 50220-20 CPC EN55922
Extrusion x 2 10201-20 CPC EN55949
2U Plain moudle 20201-20 CPC EN55876
2U XLR module 20511-20 CPC EN55880
B6x6 Screw x 4 95606 CPC EN55983
B8x13 Screw x 8 95813 CPC EN55985
USB connector Open lead CPC CS03078

schematic_1_2.pdf (28KB)