AVT-822 Embedded J1939 Controller
Hardware Revision Descriptions
Order Number Descriptions
Updated: 21 August 2014

Revision A1
Released: 14 March 2014
Embedded J1939 Controller. With J1708 interface as well. Special for one customer.
Build quantity: 4
Used this microcontroller (because I had them in-stock): MC9S12DG256CPVE.
Problems noted and corrected in the next revision.
Remove R8 and R9.
R14 to VCC.
C18, C19, and R15 to GND.
U8-14 to VCC.
Rotate P1 180 degrees.
Print a big "1" next to P1 and P3 to easily show pin #1 location
Rotate P4 180 degrees and flip.
Rotate P5 180 degrees and flip.
Move F1 to give more room next to P2 and the "+" solder pad.
R11, R12, R13, and C17 are not installed.
The first two of these boards used a switching power supply in place of the TO-220 voltage regulator.
Subsequent operational power dissipation testing indicated that the power consumption of the board and, hence, power dissipation of a linear regulator indicated it would be okay to use a linear regulator even with an input supply to +28 VDC.

Revision A2
Released: 21 March 2014
Build quantity: 30
Changed microcontroller to this: MC9S12DG128CPVE.
Slightly increased the size of the pads adjacent to P2, P4, P5, P6, and P7 to better accommodate soldering wire directly to the holes.
Changed the location of pin #1 for P2, P4, and P5 so that pin #1 is always 'up' or closer to the 'top' edge of the board.
Re-oriented the 'Debug' connector (P1) so that the comm adapter board hangs off the board, not above the board.
Do not install: R6, R7, R8, R9, R11, R12, R13, C17, P1, P4, P5, P6, P7.
Use customer provided wire harnesses for the boards in place of the P1, P4, and P7.
Solder the tab of the TO-220 voltage regulator to the via under the tab. This is done to prevent vibration of the TO-220 package and thus fatigue to the leads with eventual failure. This will not be an issue when the voltage regulator is replaced with a D2PAK device.
Thermal analysis indicated that the TO-220 package can be replaced with a D2PAK.

Revision A3
Released: pending as of 28 March 2014
Build quantity: 410 (in two builds of 60 and 350)
Final version. Assembled qty. 60 of these boards. Captured the manufacturing files and turned them over to the contract manufacturer for high quantity build.
Replaced the fuse (polyswitch) with an SMD030 device.  Was SMD050 on earlier versions.
Replaced the voltage regulator with a D2PAK device, MC7805ABD2T. Was a TO-220 device on previous versions.
Laid a big bare copper plane under the voltage regulator to improve heat dissipation.
Moved one or more bypass caps around for better spatial displacement.
Spread the pins apart for the input power wires.
Moved some components away from the edge of the board to give more room for the holder in the pick 'n place machine.
Corrected VCC to U8.

Revision xx
Released: xxx

Revision xxx
General release: xxx
Description xxx

Order Number Descriptions

AVT-822-007 : AVT-822 board only.
Status: Production boards are in-stock and available for immediate shipping.

Site Map