Question: What are the differences between FM25V20A-DGTR and FM25V20A-DGQTR
Answer: The differences are as follows:
Operating Frequency / Speed Grade
The FM25V20A-DGQTR can operate up to 33 MHz while the DGTR part can be used up to 40 MHz.
The FM25V20A-DGQTR can operate up to 105 ºC while the DGTR part can operate up to 85 ºC.
The FM25V20A-DGQTR only comes in an 8-pin DFN package while the DGTR part comes in both 8-pin DFN and 8-pin SOIC packages.
The FM25V20A devices are capable of being accessed at least 10^14 times, reads or writes. An F-RAM memory operates with a read and restore mechanism. Therefore, an endurance cycle is applied on a row basis for each access (read or write) to the memory array. The F-RAM architecture is based on an array of rows and columns of 32K rows of 64 bits each. The entire row is internally accessed once whether a single byte or all eight bytes are read or written. Each byte in the row is counted only once in an endurance calculation. The following tables show endurance calculations for a 64-byte repeating loop, which includes an opcode, a starting address, and a sequential 64-byte data stream. This causes each byte to experience one endurance cycle through the loop.
The time to reach endurance limit for DGQTR for a repeating 64-byte loop is listed in the following table.
The time to reach endurance limit for DGTR for a repeating 64-byte loop is listed in the following table.