Measurement Computing USB-1602HS-2AO - Manual (Page 42)

USB-1602HS-2AO User's Guide Specifications
42
Pacing sources
Table 12. Pacing specifications
Parameter Specification
Pacer clocks (2)
 Input pacer
 Output pacer
Input pacer:
 For pacing A/D, DIN and Counter signals
 Can be internally generated or externally supplied (XAPCR)
 XAPCR is accessible from front BNC or rear SCSI connector
Output pacer:
 For pacing DAC, DOUT and Timer/PWM signals
 Can be internally generated or externally supplied (XDPCR)
Input pacer clock sources (2)
 Internal, programmable
 External (XAPCR)
Internal, programmable:
 Analog channels from 500 ns to 1000s in 20.83 ns steps.
 DIN channels and counters from 125 ns* to 100 s in 20.83 ns steps.
 Can be configured to pace AO and/or DOUT channels
External, TTL level input (XAPCR):
 A/D channels down to 500 ns minimum
 DIN channels and counters down to 125 ns* minimum
 Can be configured to pace DAC and/or DOUT channels
Input pacer rate
Internal or external, (XAPCR) source Analog: 2 MHz maximum
Digital: 8 MHz if no analog channels are enabled. 2 MHz with
analog channels enabled.
Pacer input high voltage 2.0 V minimum, 5.5 V maximum
Pacer input low voltage 0.8 V maximum, 0 V minimum
Minimum pulse width 50 ns high, 50 ns low
Output pacer clock sources (4)
 Internal output pacer clock, (independent of input pacer clock)
 External output pacer clock, XDPCR
 Internal input pacing clock
 External input pacing clock, XAPCR
Output pacer rate
Internal or external, (XDPCR) source Analog: 1.0 MHz maximum
Digital: 8 MHz, if no analog outputs are enabled, (1 MHz if
DAC outputs are enabled)
Internal pacer routed to BNC or SCSI conn.
 Output high voltage (IOH = –2.5 mA):
 Output low voltage (IOL = 2.5 mA): XAPCR or XDPCR
 2.4 V minimum
 0.4 V maximum