Home page



72-P Small Outline DIMMs

The DIMMCHECK 72P (p/n INN-8484-4) enables SIMCHECK to test 72-pin SO DIMM (36x2 pin Small-Outline Dual-Inline-Memory-Module) modules with basic configurations of 18, 32, and 36 bits. This adapter can also be used with SIMCHECK II. The test can be selected by the user at 5V or 3.3V.

The DIMM module (JEDEC MO-160) has an internal architecture similar to the JEDEC 72-pin SIMM standard with the main differences being the arrangement of the 72 pins along a double sided 36x2 edge connector and the use of TSOP DRAM chips which results in a remarkably thin package. The DIMMCHECK 72P is conveniently installed in the 40-BIT PORT expansion slot, and is automatically recognized by SIMCHECK. All memory cells are fully tested, with parallel write/read of 36 bits. The test procedure is similar to the 40-BIT PORT test.

IMPORTANT NOTE: This adapter requires the SIMCHECK PLUS.

40-BIT PORT 3.3V COMPATIBILITY: Your 40-BIT PORT should have serial number #20158 or higher for compatibility with the new 3.3V tests performed with this adapter. This serial number cutoff corresponds to May 9, 1995 or later. If your 40-BIT PORT has an earlier serial number, the 3.3V tests will be actually done at 3.7V-4.1V instead of 3.0V-3.5V. Please consult application note INN-8448-APN09 "40-BIT PORT 3.3V COMPATIBILITY MODIFICATION" which comes with this adapter, or contact your dealer.


This tester connects to SIMCHECK via the 40-BIT PORT (see Section 7.8). Plug the adapter into the 40-BIT EXPANSION PORT of the 40-BIT PORT only when SIMCHECK is turned OFF.

CAUTION: Failure to turn SIMCHECK OFF when connecting or disconnecting the DIMMCHECK 72P to the 40-BIT PORT may result in damage to the PAL chip of the DIMMCHECK 72P!

HANDLING THE 72-P DIMM: The delicate DIMM socket has two latches which are pushed in the directions of the arrows on the board to release the DIMM module. The DIMM module should be inserted carefully, at about a 30 degree angle into the socket insuring that the notch, indicating pin 1, is on the left side. Push the two latches in the directions of the arrows and carefully push the DIMM to a horizontal position. The latches should go over the module's top notches for retention once the module is in the horizontal position. The DIMM is removed by releasing the latches and pulling the DIMM upward to the same insertion angle. Once lifted, the DIMM can easily slide out of the socket.

Turn SIMCHECK ON once the DIMMCHECK 72P is installed in the 40-BIT PORT and insert the first DIMM module. THERE IS NO NEED TO SETUP SIMCHECK, as it automatically recognizes this tester. After the first DIMM has been tested and SIMCHECK returns to the STANDBY mode, the presence of the DIMMCHECK 72P is recognized.

5V/3.3V VOLTAGE SELECTION: The DIMMCHECK 72P can test the DIMM modules at either 5V or 3.3V. Once the first DIMM module is inserted, press F1 to start the test. Upon initial startup, the test voltage selection menu will appear.

Press F2 to set the test at 3.3V, or press F1 to select the default 5V test (if no selection is made within a few moments, SIMCHECK will default to 5V). The BASIC test follows the voltage selection. If the 3.3V test was selected, you will see the message '3V' at the top right corner of the display during BASIC test and the final test of the EXTENSIVE test. The voltage selection menu WILL NOT APPEAR on subsequent tests - the voltage selection you have made upon startup remains in effect throughout all subsequent tests. You can change the voltage selection setting using the setup mode: from STANDBY mode, press F2, then F1, and the above voltage selection menu will reappear. After the voltage selection, the standard setup menus will appear; if no additional setups are needed, simply press ESC after your selection. You can also change the voltage selection by simply turning SIMCHECK off and on. The voltage selection menu will appear as soon as you start a new test.

3.3V vs. 5V TEST: You can distinguish between a 3.3V DIMM and a 5V DIMM by the length of the lower tab near pin 1. The 3.3V DIMM's tab is 3-3.3 mm long while the 5V DIMM's tab is 6.2-6.5 mm long. Most 5V DIMM modules will still be testable at 3.3V, but you will notice a large decrease in access time at the 3.3V tests. A 3.3V DIMM module can still be tested at the 5V test without damage, as most 3.3V DRAM chips are "5V Tolerable". You will still notice a better speed at 5V than at 3.3V, but the difference will be much smaller than with the 5V DIMMs. Future DIMM modules may come with 3.3V devices which are not 5V tolerable. Such devices should be tested only at the 3.3V setup.

The DIMMCHECK 72P test procedure is similar to the 40-BIT PORT module test.

Required EPROM Version: 2.34 or above.


Back To Home Page