hcs361 Microchip Technology Inc., hcs361 Datasheet - Page 13

• Manufacturer Part Number: hcs361
• Description: Keeloq Code Hopping Encoder
• Manufacturer: Microchip Technology Inc.

FIGURE 4-2:
2002 Microchip Technology Inc.
WAKE-UP:
CODE WORD:
WAKE-UP (TXWAK=1)
VPWM BIT ENCODING:
VPWM TRANSMISSION SEQUENCE:
1
T
18xT
BP
E
1
Dead Time
VPWM TRANSMISSION FORMAT (MOD = 1)
Preamble
T
BP
6
33% Duty Cycle Wake-Up sequence 250xT
Preamble Header Encrypt Fixed
10xT
on Transition Low to High
on Transition High to Low
SPM=1
SPM=0
Pulse
E
Sync
10
1st CODE WORD
10xT
E
Header
Code Word
T
E
T
BP
Encrypted Portion
T
T
T
BP
E
T
2
E
X
BP
LOGIC 0
LOGIC 0
T
E
Guard
E
Preamble Header Encrypt
84
T
T
E
2
BP
T
X
LOGIC 1
BP
LOGIC 1
Fixed Code Portion
T
E
Dead Time 258xT
HCS361
DS40146E-page 13
E
Guard
Time