Here is a picture of the Superfly cartridge for the TI-99/4A console from Milton Bradley. Ninerpedia:Superfly cartridge
All MB cartridges use the same kind of PCB. The biggest chip on this board is supposedly the ROM. The two smaller ones top/middle are GROMs; the two ones top/right are RAM circuits. Top/left is a latch that is used for bank selection in the ROM.
I could not find specs for the big chip. I guess it is a 32Kx8 ROM. The NCR number (8342A) is different for each cartridge. The only constant seems to be the 1500536.