DS87C520_1 Datasheet, PDF (42/42 Pages) Dallas Semiconductor – EPROM/ROM High-Speed Micro

DS87C520/DS83C520
DATA SHEET REVISION SUMMARY
The following represent the key differences between 07/06/98 and 07/03/00 version of the DS87C520
data sheet. Please review this summary carefully.
1. Corrected P0 pinout description for TQFP package
2. Clarified point at which reset delay begins
The following represent the key differences between 02/20/97 and 07/06/98 version of the DS87C520
data sheet. Please review this summary carefully.
1. Update PMM operating current estimates
2. Added note to clarify I_IL specification.
3. Added note to prevent accidental corruption of Watchdog Timer count while changing counter length.
4. Changed minimum oscillator frequency to 1 MHz when using external crystal.
5. Changed RST pulldown resistance from 170 kΩ to 200 kΩ maximum.
6. Corrected “Data memory write with stretch” diagrams to show falling edge of ALE coincident with
rising edge of C3 clock.
The following represent the key differences between 110195 and 02/20/97 version of the DS87C520 data
sheet. Please review this summary carefully.
1. Update ALE pin description.
2. Add note pertaining to erasure window.
3. Add note pertaining to internal MOVX SRAM.
4. Change note 10 from RST=5.5V to RST=V_CC.
5. Change serial port mode 0 timing diagram label from t_QVXL to t_QVXH.
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