NetDAQ
Service Manual
2-2
2-31.
Digital Kernel ............................................................................... 2-13
2-32.
Reset Circuits............................................................................ 2-14
2-33.
Microprocessor ......................................................................... 2-14
2-34.
Address Decoding..................................................................... 2-16
2-35.
Flash Memory........................................................................... 2-18
2-36.
Static RAM ............................................................................... 2-18
2-37.
Real-Time Clock....................................................................... 2-19
2-38.
FPGA (Field Programmable Gate Array)................................. 2-19
2-39.
Serial Communication (Guard Crossing) ................................. 2-21
2-40.
RS-232 Interface....................................................................... 2-21
2-41.
Ethernet Interface ..................................................................... 2-22
2-42.
Digital Inputs and Outputs............................................................ 2-24
2-43.
Digital Input Threshold ............................................................ 2-24
2-44.
Digital Input Buffers................................................................. 2-24
2-45.
Digital and Alarm Output Drivers ............................................ 2-25
2-46.
Totalizer Input .......................................................................... 2-25
2-47.
External Trigger Circuits .......................................................... 2-25
2-48.
A2 Display PCA Circuit Description................................................. 2-26
2-49.
Main PCA Connector ................................................................... 2-26
2-50.
Front Panel Switches .................................................................... 2-27
2-51.
Display.......................................................................................... 2-28
2-52.
Beeper Drive Circuit..................................................................... 2-28
2-53.
Watchdog Timer and Reset Circuit .............................................. 2-29
2-54.
Display Controller ........................................................................ 2-29
2-55.
A3 A/D Converter PCA Circuit Description ..................................... 2-31
2-56.
Stallion Chip ................................................................................. 2-33
2-57.
Input Protection ............................................................................ 2-33
2-58.
Input Signal Conditioning ............................................................ 2-33
2-59.
Function Relays ............................................................................ 2-33
2-60.
Channel Selection Circuitry ......................................................... 2-34
2-61.
DC Volts and Thermocouples Measurement Circuitry................ 2-34
2-62.
Ohms and RTD Measurement Circuitry....................................... 2-36
2-63.
AC Volts Measurement Circuitry................................................. 2-37
2-64.
Frequency Measurements............................................................. 2-37
2-65.
Active Filter (ACV Filter) ............................................................ 2-37
2-66.
Voltage Reference Circuit ............................................................ 2-38
2-67.
Analog/Digital Converter Circuit ................................................. 2-39
2-68.
Autozero ................................................................................... 2-39
2-69.
Integrate .................................................................................... 2-40
2-70.
Deintegrate1.............................................................................. 2-42
2-71.
Deintegrate2.............................................................................. 2-42
2-72.
Overhead................................................................................... 2-42
2-73.
Inguard Digital Kernel Circuitry .................................................. 2-42
2-74.
Open Thermocouple Detect Circuitry............................................ 2-43
2-75.
A4 Analog Input PCA Circuit Description........................................ 2-43
2-76.
A1 Main to A3 A/D Converter Communications .................................. 2-44
2-77.
Special Codes..................................................................................... 2-44
2-78.
Resets ................................................................................................. 2-44
Summary of Contents for NetDAQ 2640A
Page 14: ...NetDAQ Service Manual x...
Page 46: ...NetDAQ Service Manual 2 4...
Page 106: ...NetDAQ Service Manual 2 64...
Page 108: ...NetDAQ Service Manual 3 2...
Page 164: ...NetDAQ Service Manual 4 42...
Page 206: ...NetDAQ Service Manual 6 2...
Page 218: ...NetDAQ Service Manual 6 14 2645A 1601 Figure 6 2 A1 Main PCA Assembly...
Page 220: ...NetDAQ Service Manual 6 16 2620A 1601 Figure 6 3 A2 Display PCA Assembly...
Page 230: ...NetDAQ Service Manual 6 26 2645A 1603 Figure 6 5 2645A A3 A D Converter PCA Assembly...
Page 234: ...NetDAQ Service Manual 7 2...
Page 242: ...2640A 2645A Service Manual 7 10 Figure 7 2 A2 Display PCA Assembly 2620A 1602...
Page 243: ...Schematic Diagrams 7 7 11 Figure 7 2 A2 Display PCA Assembly cont 2620A 1002...
Page 251: ...Schematic Diagrams 7 7 19 2645A 1603 Figure 7 4 2645A A3 A D Converter PCA Assembly 2645A 1603...
Page 258: ...2640A 2645A Service Manual 7 26 Figure 7 5 A4 Analog Input PCA Assembly 2620A 1604...
Page 260: ...2640A 2645A Service Manual 7 28...