Counter/Timer Specifications
Specifications
These specifications are typical for 25 °C unless otherwise noted.
Timing I/O
General-Purpose Up/Down Counter/Timers
Number of channels
DMA channels
NI 6601 ......................................................
NI 6602/6608.............................................
1
3
NI 6601 ...................................................... 4 up/down counters
NI 6602/6608............................................. 8 up/down counters
Counter size/number of bits............................. 32 bits
Prescalers (per counter) ................................... 3 bits (divided by 8)
1 bit (divided by 2)
Disabled (by default)
Power-on state ................................................. Input (high-Z), pulled low
Pull down current: 10 µA (min) to 200 µA (max)
Hysteresis......................................................... 300 mV Schmitt triggers
Compatibility .................................................... 5 V TTL/CMOS
Oven-Controlled Crystal Oscillator (OCXO) (NI 6608 Only)
Frequency ......................................................... 10 MHz
OCXO accuracy................................................. 0.00000ꢁ5ꢀ (ꢁ5 ppb)
Warm-up time (to within 0.02 ppm
of operating frequency) ............................. 5 minutes
Frequency stability versus
supply voltage change ( 5ꢀ).................... ≤ 0.005 ppm
Temperature stability (0 to 50 °C).................... ≤ 0.005 ppm
Drift in frequency ............................................. ≤ 0.00045 ppm/day
≤ 0.045 ppm/year
Allowed frequency adjustment........................ 0.5 ppm, typical
Digital logic levels
Level
Minimum
Maximum
Note: You can use the OCXO to replace the PXI 10 MHz backplane clock when the PXI-6608 is installed
in the PXI star trigger slot (Slot 2). You can also use it as the counter source or gate in any slot.
Input low voltage
Input high voltage
Output low voltage (Iout = 4 mA)
Output high voltage (Iout = 4 mA)
-0.3 V
2.0 V
–
0.8 V
5.25 V
0.4 V
–
Digital I/O
2.4 V
Number of channels......................................... Up to 32 input/output
Compatibility .................................................... 5 V TTL/CMOS
Power-on state ................................................. Input (high-Z), pulled low
Pulldown current .............................................. 10 µA (min) to 200 µA (max)
Hysteresis......................................................... 300 mV Schmitt triggers
Data transfers .................................................. Unstrobed I/O
Base clocks available
NI 6601 ...................................................... 100 kHz and 20 MHz
NI 6602/6608............................................. 100 kHz, 20 MHz, and 80 MHz
Base clock accuracy (NI 6601 and NI 6602) .... 0.005ꢀ (50 ppm)1
Base clock (OCXO) accuracy (NI 6608)............. 0.00000ꢁ5ꢀ (ꢁ5 ppb)
Maximum source frequency
External source selections ............................... I/O connector, RTSI/PXI Trigger lines, software selectable
External gate selections................................... I/O connector, RTSI/PXI Trigger lines, software selectable
1 If a PXI-6608 is installed in slot 2 of a PXI chassis, then the PXI-6608 and any PXI-6602
installed in that chassis inherit a base clock accuracy of 0.00000ꢁ5ꢀ (ꢁ5 ppb).
Digital logic levels
Level
Minimum
Maximum
Input low voltage
Input high voltage
Output low voltage (Iout = 4 mA)
Output high voltage (Iout = 4 mA)
-0.3 V
2.0 V
–
0.8 V
5.25 V
0.4 V
–
2.4 V
Family
Without Prescaling With Prescaling
NI 6601
NI 6602
NI 6608
20 MHz
80 MHz
80 MHz
60 MHz
125 MHz
125 MHz
RTSI Bus (PCI Only)
Trigger lines......................................................
Minimum pulse width
ꢁ
for trigger and clock .................................. 25 ns
Minimum source pulse duration
With prescalers ......................................... 3.5 ns; edge-detect mode
Without prescalers.................................... 5 ns; edge-detect mode
Minimum gate pulse duration.......................... 5 ns; edge-detect mode
Frequency ranges to measure or generate
PXI Trigger Bus (PXI Only)
Trigger lines......................................................
Star trigger .......................................................
6
1
Bus Interface
Data Transfers
PCI, PXI ............................................................. Master, slave
Family
Frequency to Measure
Min/Max Frequency to Generate
NI 6601
NI 6602
NI 6608
20 MHz
80 MHz
80 MHz
10 MHz
40 MHz
40 MHz
Power Requirements
Device
+5 VDC ( 5ꢀ)ꢁ
Power Available at I/O Connector
NI 6601
NI 6602
NI 6608
0.4 to 0.ꢁ5 A
0.5 to 1.5 A
1 to 2.5 A
+4.65 to +5.25 VDC, 1 A
+4.65 to +5.25 VDC, 1 A
+4.65 to +5.25 VDC, 1 A
For more information, please visit ni.com/info and enter exatzz.
Transfer modes................................................. DMA, interrupts, programmed I/O
*Excludes power consumed through I/O connector
Transfer rates
DMA1,2
Finite Operation
Interrupt1,3
Finite Operation
Physical
Dimensions (not including connectors)
Buffer Size (S)
Rate (MS/s)
Buffer Size (S)
Rate (kS/s)
PCI.............................................................. 1ꢁ.5 by 9.9 cm (6.9 by 3.9 in.)
PXI.............................................................. 16.0 by 10.0 cm (6.3 by 3.9 in.)
I/O connector.................................................... 68-pin male SCSI-II type
100
1,000
10,000
5.0
4.2
2.0
1.8
100
1,000
10,000
55
49
49
48
100,000
100,000
Environment
1Values may vary depending on your computer hardware, operating system and system
activity. Benchmark data was determined on a Pentium II 400 MHz computer with 64 MB
RAM running Windows 98 and LabVIEW using one counter of a PCI-6602. 2The number of
simultaneous DMA transfers you can perform is equivalent to the DMA channels available on
your device. 3The rate is based on one counter using the interrupts. If multiple counters
share interrupts, the transfer rate per counter is lower.
Operating temperature..................................... 0 to 50 °C
Storage temperature........................................ -20 to ꢁ0 °C
Relative humidity ............................................. 10 to 90ꢀ, noncondensing
Certifications and Compliances
CE Mark Compliance
Continuous Operation
Buffer Size (MS) Rate (kS/s)
Continuous Operation
Buffer Size (kS) Rate (kS/s)
50 15
50
28
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