Specifications

LIST OF FIGURES
7.1 Block diagram of uplink module’s hardware interconnect . . . 68
7.2 I
2
C master to slave multi-byte data exchange . . . . . . . . . 74
7.3 I
2
C slave to master multi-byte data exchange . . . . . . . . . 74
7.4 I
2
C protocol used in uplink module . . . . . . . . . . . . . . . 75
8.1 DC rail output of SMPS. . . . . . . . . . . . . . . . . . . . . . 93
8.2 Circuit diagram of s witching DC-DC converter . . . . . . . . . 94
8.3 Battery SOC vs Open circuit voltage. . . . . . . . . . . . . . . 95
8.4 SLA battery target charge voltage vs temperature. . . . . . . . 96
8.5 Battery charging circuit and main supply input. . . . . . . . . 97
8.6 finite state machine of charging algorithm. . . . . . . . . . . . 99
8.7 Discharge periods vs. discharge rates . . . . . . . . . . . . . . 101
A.1 Schematic of push-pull output single channel receiver reader . A-2
A.2 PCB Layout: push-pull output . . . . . . . . . . . . . . . . . A-3
A.3 PCB Layout: single-ended output . . . . . . . . . . . . . . . . A-4
A.4 Populated dual channel receiver board . . . . . . . . . . . . . A-5
B.1 RFID co-ordinator circuit diagram . . . . . . . . . . . . . . . B-2
B.2 RFID co-ordinator PCB top solder side . . . . . . . . . . . . . C-1
B.3 RFID co-ordinator PCB bottom solder side . . . . . . . . . . . C-1
C.1 Uplink module PCB top solder side . . . . . . . . . . . . . . . C-5
C.2 Uplink module PCB bottom solder side . . . . . . . . . . . . . C-6
C.3 Uplink module full circuit diagram . . . . . . . . . . . . . . . C-7
C.4 Uplink module populated board . . . . . . . . . . . . . . . . . C-8
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