M396F V2.7

Replica of a 386SX Mainboard

PCB Revision History

  • V0.1 Initial revision 2022 made with Sprint-Layout
  • V0.2 Silkscreen updated, component positions and mounting holes modified

Specs

This replica of a 386SX motherboard is based on the SARC RC2016A chipset. Supported are 386SX or CX486SLC 25/33/40 MHz CPUs. A socket for the optional 80387SX coprocessor is available. The RAM reaches from 512kb to 16MB. I recommend faster 60ns RAM. The manual, jumper settings and useful downloads can be found here https://theretroweb.com/motherboards/s/pcchips-m396f-ver.2.6#downloads

Images

Top view

blank PCB

Bill of materials

Quantity Description PCB/Schematic's Reference
4 CAP CER 30 pF RM 5,0 C11, C13, C36, C38
3 CAP CER 47 pF RM 5,0 C12, C15, C66
1 CAP CER 220 pF CXX (Backside see notice)
1 CAP CER 4,7 nF RM 5,0 C16
1 CAP CER 100 pF nF RM 5,0 C65
10 CAP CER 100 nF RM 5,0 C10, C17, C20, C22, C32, C33, C43, C45, C47, C50
14 CAP ELKO 10 uF 25V RM 2,5 C1, C2, C4, C9, C14, C18, C28, C29, C34, C37, C40, C44, C46, C48
2 DIODE 1N4148 D1, D2
6 16 Bit ISA Socket J2, J3, J4, J5, J6, J7
1 AT Power connector J8
1 Battery BAT
1 CON 4 PIN JP1 external Battery
1 CON 2 PIN JP2 Display type
1 CON 5 PIN JP3 Power LED / Key lock
1 CON 4 PIN JP4 Speaker
1 CON 2 PIN JP5 Turbo LED
1 CON 2 PIN JP6 Turbo switch
1 CON 2 PIN JP7 Reset switch
3 CON 3 PIN JP8, JP9, JP10 CPU clock select
1 3906 Q1
2 3904 Q2, Q3
2 RES 0 Ohm 5% 1/4W L1, L2
2 RES 22 Ohm 5% 1/4W R20, R25
2 RES 56 Ohm 5% 1/4W R17, R18
1 RES 150 Ohm 5% 1/4W R27
1 RES 220 Ohm 5% 1W R7
2 RES 330 Ohm 5% 1/4W R13, R28
3 RES 470 Ohm 5% 1W R8, R23, R26
2 RES 1 k Ohm 5% 1/4W R6, R31
4 RES 4,7 k Ohm 5% 1/4W R14, R15, R16, R22
9 RES 10 k Ohm 5% 1/4W R2, R3, R4, R9, R10, R19, R21, R29, R30
1 RES 51 k Ohm 5% 1/4W R5
2 RES 1 M Ohm 5% 1/4W R12, R24
1 RES 2 M Ohm 5% 1/4W R11
2 RES Network 4,7 k Ohm bussed RP1, RP2
1 RES Network 330 Ohm bussed RP3
3 RES Network 10 Ohm parallel RP4, RP5, RP6
1 RES Network 100 Ohm parallel RP7
1 IC SARC 6042 o. VIA VT82C42 U1
1 IC 74HC05AP U2
1 IC BIOS U3
1 IC W85C168 U4
1 IC TC4069UBP U5
1 IC PLL52C05S o. TK9107-2 U6
1 IC CPU U7
1 IC Coprocessor U8
1 IC Chipset U9
4 IC RAM (60ns) U10, U11, U12, U13
1 Quarz 32,768 kHz X1
1 Quarz 14,31818 MHz X2

Notice

Backside position CXX (CAP CER 220 pF axial or 0805 SMD)

Mounting holes

This board uses the mounting holes marked in green. Modern AT cases often only have the red marked holes.

Licence

The project is free for non-commercial reproduktion. Do not sell it on ebay or other platforms for profit. Do not make a closed source. Share your experiences and ideas with the community.