MAX66140 Maxim, MAX66140 Datasheet - Page 7

• Manufacturer Part Number: MAX66140
• Description: The MAX66140 combines 1024 bits of user EEPROM with secure hash algorithm (SHA-1) challenge-and-response authentication (ISO/IEC 10118-3 SHA-1), a 64-bit unique identifier (UID), one 64-bit secret, and a 13
• Manufacturer: Maxim

first half of the bit transmission time, switching to the
lower subcarrier for the second half. See Figure 13 for
details. The transmission of the SOF pattern takes the
same time as transmitting 4 bits (approximately 151µs
at a high data rate or approximately 604µs at a low data
Figure 8. Downlink Data Coding (Case “1 Out of 4,” Carrier Not Shown)
Figure 9. Downlink SOF for “1 Out of 256” Coding (Carrier Not Shown)
PULSE POSITION "00"
PULSE POSITION "01" (1 = LSB)
PULSE POSITION "10" (0 = LSB)
PULSE POSITION "11"
~ 9.44μs
~ 9.44μs
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ABRIDGED DATA SHEET
ISO 15693-Compliant Secure Memory
~ 9.44μs
~ 28.32μs
~ 37.76μs
~ 47.20μs
~ 66.08μs
~ 9.44μs
~ 75.52μs
~ 75.52μs
~ 75.52μs
~ 75.52μs
rate). The SOF is distinct from any 4-bit data sequence.
The EOF pattern is equivalent to a SOF being transmit-
ted backwards. The exact duration of the SOF and EOF
varies slightly depending on the use of one or two sub-
carriers (Figures 14 and 15, respectively).
~ 9.44μs
~ 37.76μs
~ 9.44μs
~ 9.44μs
9