The TTU-2820™’s GPS receiver has the following specifications:
50 channel GPS receiver
Accuracy: 2.5 meter CEP (with SA off)
-162dBm Tracking Sensitivity
] 3.4 I/O Descriptions
The TTU-2820™ provides the following I/O:
Digital Inputs
Input 0: Ignition Sense (Always biased low)
Input 1: Generic Digital Input (high or low bias per S-158)
Input 2: Generic Digital Input (high or low bias per S-158)
Input 3: Not Available
Input 4: Not Available
Input 5: Motion Sensor (low = no motion, high = motion)
Input 6: Power Switch State (low = external power, high = internal battery)
Input 7: Battery Voltage Critical Sensor ( low = VBatt ok, high = VBatt low.
3500mV threshold)
Input 8: High Temperature Sensor (low = below Temp Threshold, high = above
Temp threshold. Temp Threshold = 300)
Analog to Digital Inputs
A/D 0: External Power Supply Monitor
A/D 1: Generic External Analog to Digital Input
A/D 2: GPS Antenna Monitor
A/D 3: uP Temperature
A/D 4: uP Voltage
A/D 5: Battery Voltage
A/D 6: Temperature Sensor
A/D 7: Vcc Sys
Outputs:
Output 0: Standard Open Collector Relay Output
Output 1: Standard Open Collector Relay Output
Output 2: Standard Open Collector Relay Output
Output 3: Not Available
Output 4: Power Supply Switch (cleared = switch to external power, set = switch
to internal power)
Output 5: Enable/Disable Battery charging (cleared = enable battery charging, set
= disable battery charging)
