User manual

4 U2300A Series DAQ Service Guide
1 Characteristics and Specifications
General Purpose Digital Counter
Model Number U2351A | U2352A | U2353A | U2354A
Maximum count (2³¹-1) bits
Number of channels Two independent up/down counter
Compatibility TTL
Clock source Internal or external
Base clock available 48 MHz
Maximum clock source frequency 12 MHz
Input frequency range 0.1 Hz to 6 MHz at 50% duty cycle
Pulse width measurement range 0.167 µs to 178.956 s
Analog Trigger
Model Number U2351A | U2352A | U2353A | U2354A
Trigger source All analog input channels, External analog trigger (EXTA_TRIG)
Trigger level ±Full Scale for internal; ±10 V for external
Trigger conditions Above high, below low and window (software selectable)
Trigger level resolution 8 bits
Bandwidth 400 kHz
Input Impedance for EXTA_TRIG 20 kΩ
Coupling DC
Overvoltage Protection Continuous for ± 35 V maximum
Digital Trigger
Model Number U2351A | U2352A | U2353A | U2354A
Compatibility TTL/CMOS
Response Rising or falling edge
Pulse width 20 ns minimum
Calibration
[3]
Model Number U2351A | U2352A | U2353A | U2354A
On board reference voltage 5 V
Temperature drift ±2 ppm/°C
Stability ±6 ppm/1000 hours