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Fluke Timer Counters and Frequency Counters PM 6680B, PM6681, PM6685

Measurement Functions MeasurementFunctions

Time Interval, Pulse Width, Rise/Fall Time, Frequency, Burst Frequency, Period,Ratio f1/f2, Phase, Duty Factor, Totalize

Frequency Input A: (PM6681): 10 -10 Hz to 300 MHz(PM6680B): 10 -10 Hz to 225 MHzInput B: 10 -10 Hz to 100 MHzInput C: (Optional Input Pre-Scaler)(PM9621): 70 MHz to 1.3 GHz(PM9624): 100 MHz to 2.7 GHz(PM9625B): 150 MHz to 4.2 GHzResolution:(PM6681): 11 digits/s measurement time(PM6680B): 10 digits/s measurement time

Burst FrequencyInput A,B,C Frequency Range Input A:(PM6681): Up to 300 MHz(PM6680B): Up to 160 MHzFrequency Range Input B:Up to 100 MHzFrequency Range Input C:(PM6681) Up to 3.0 GHz with optionsStart Delay Range: (PM6681): 200 ns to 1s, 100 ns resolution

Period A Range: (PM6681): 3.3 ns to 10 10 s(PM6680B): 6 ns to 10 10 sResolution:

(PM6681): 11 digits/s measurement time(PM6680B): 10 digits/s measurement time

Ratio A/B, C/B Range: 10 -9 to 10 15 Frequency Range: Input A,B: 10 -10 Hz to 160 MHzInput C: See input C frequency range.

Time IntervalA to B

Range: 0 ns to 10 10 sResolution: (PM 6681): single shot 50 ps (1 ps average)(PM 6680B): 250 psFrequency Range: Up to 160 MHz

Pulse Width A Range: 3 ns to 10 10 s

Frequency Range: Up to 160 MHzRise and Fall Time Range: 3 ns to 10 10 s

Frequency Range: Up to 160 MHzInput Amplitude:(PM6681) > 250 mV p-p(PM6680B) > 500 mV p-p

Phase A Relative B Range: -180 to +360Resolution: 0.01

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Frequency Range: 0.03 Hz to 160 MHz

Duty Factor A Range: 0 to 1Frequency Range: 0.11 Hz to 160 MHz

Totalize A,B Range: 0 to 10 17 , 0 to 10 10 in A-B modesFrequency Range: 0 to 160 MHzA Gated by B: Event counting on input A during the presence of a pulse oninput B. Single or cumulative event counting during set measuring time.A start/stop by B: Event counting on input A between two consecutive pulseson B.Manual A-B: Input A minus input B event counting with manual start/stop.Manual/Timed A-B: Input A minus input B event counting with manualstart/stop. Stop after set measuring time. Time counted from first trigger eventon A.

AC/DC Voltage A,B Range: -50V to +50 VFrequency Range: (PM6681) DC, 1 Hz to 100 MHz(PM6680B) DC, 100 Hz to 100 MHzMode: V max, V min, V p-pResolution:(PM6681) 1.25 mV(PM6680B) 20 mVGated Volt: External masking of unwanted signal components such asovershoot

Optional TimeBase Standard: PM668-/-1-(Non -Retrofit)

Calibration adjustment tolerance *** at +23C 3C: < 1 x 10 -6 Uncertainty due to: Aging /24 hr: N/A * Aging /month: < 5 x 10 -7 Aging /year: < 5 x 10 -6 Temperature Stability (reference temp at +23C): 0-50C: < 1 x 10 -5 20C -26C: 3 x 10 -6 Line Voltage variation of 10%: < 1 x 10 -8 Power On Stability: Not SpecifiedTotal Uncertainty **** at 2 (95%) confidence interval and at 23C 3C: After 1 Year Cal interval < 7 x 10 -6 After 2 Year Cal interval < 1.2 x 10 -5 Total Uncertainty **** at 2 (95%) confidence interval and at 0-50C: After 1 Year Cal interval < 1.2 x 10 -5 After 2 Year Cal interval < 1.5 x 10 -5

TCXO: PM668-/-2-(PM9678B/021)

Calibration adjustment tolerance *** at +23C 3C: < 2 x 10 -7 Uncertainty due to: Aging /24 hr: N/A * Aging /month: < 1 x 10 -7 Aging /year: < 5 x 10 -7 Temperature Stability (reference temp at +23C): 0-50C: < 1 x 10 -6 20C -26C: < 2 x 10 -7 (typical values)

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Line Voltage variation of 10%:

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** After 48 hours continuous operation*** Calibration Adjustment Tolerance: Is the maximal tolerated deviation from the true 10MHz frequencyafter a calibration. When the reference frequency does not exceed the tolerance limits at the momentof calibration, an adjustment is not needed.**** Total uncertainty: Is the total possible deviation from the true 10MHz value under influence of frequency drift due to aging and ambient temperature variations versus the reference temperature. The

operating temperature range and the calibration interval are part of this specification.

Input and Output Specifications Input A & B(PM6681)

Frequency Range:AC coupled: 10 Hz to 300 MHzDC coupled: DC to 300 MHzCoupling: AC or DCRise time: Approximately 1.1 nsImpedance: 1 M //15 pf or 50 , VSWR< 2:11 M //65 pF or 50 with PM 9611/80 rear panel inputsTrigger Slope: Positive or negativeChannel Inputs: Separate, Common A or Swapped

Max. channel timing difference: 500 psSensitivity (SineWave):20 mV, up to 100 MHz30 mV, 100 MHz to 200 MHz40 mV, 200 MHz to 250 MHz60 mV, > 250 MHzPulse Width: > 5 ns at 60 mV p-p, > 3 ns at 90 mV p-pAttenuation: X1 or X10Hysteresis Window (x1): 20 mV p-pVariable Hysteresis A (x1): 30 mV p-p to 10 V p-p up to 120 MHzDynamic Range: 60 mV p-p to 10 V p-p

Trigger Trigger Level: Read out on display

Range: (x1): -5V to + 5V(x10): -50V to + 50VResolution: (X1): 1.25 mVUncertainty: (x1): (4 mV + 1% of trigger level)

Auto Trigger Level Trigger level is automatically set to 50% of input signal.Frequency: > 1Hz

Low Pass Filter A 100 kHz fixed. > 40 dB attenuation at 1 MHz

Digital Low PassFilter

1 Hz to 5 MHz using trigger hold off

Trigger Indicator Tri-State LED indicator

Trigger Slope Positive or Negative

Damage Level 1 M Impedance: 350V (DC + AC peak) at DC to 440 Hz, falling to 12 Vrms(x1) and 120 V rms (x10) at 1 MHz50 Impedance: 12V rms

Input A & B(PM6680B)

Frequency Range: AC coupled: 10 Hz to 225 MHzDC coupled: DC to 225 MHz

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Coupling: AC or DCRise time: Approximately 1.5 nsImpedance: 1 M //30pf or 50 , VSWR < 2:11 M //80pf or 50 (with PM 9611 /80 rear panel inputsChannel Inputs: Separate, Common A or SwappedMax. channel timing difference: 1 nsSensitivity: 20 mV, up to 100 MHz30 mV, 100 MHz to 200 MHz40 mV, > 200Pulse Width: > 5 ns at 60 mV p-p, > 3 ns at 90 mV p-pAttenuation: X1 or X10Hysteresis Window (x1): 30 mV p-pVariable Hysteresis A (x1): 60 mV p-p to 10 V p-p up to 120 MHzDynamic Range: 60 mV p-p to 10 V p-p

Trigger Trigger Level: Read out on displayRange: (x1): -5.1V to + 5.1V(x10): -51V to + 51VResolution: (X1): 20 mVUncertainty: (x1): (20 mV + 1% of trigger level)

Auto Trigger Level Trigger level is automatically set to 50% of input signal.(10% and 90% for Rise/Fall Time,75% and 25% for variable hysteresis A)Frequency: > 100 Hz, > 150 mV p-p

Low Pass Filter A 100 kHz fixed. > 40 dB attenuation at 1 MHz

Digital Low PassFilter

1 Hz to 5 MHz using trigger hold off

Trigger indicator Tri-State LED indicator

Trigger Slope Positive or Negative

Max. Voltagewithout Damage

1 M Impedance: 350V (DC + AC peak) at DC to 440 Hz, falling to 12 Vrms(x1) and 120 V rms (x10) at 1 MHz.50 Impedance: 12V rms

Optional Pre-Scalers Input C (PM 9621) Frequency Range: 70 MHz to 1.3 GHz

Pre-Scaler Factor: 256 (PM6680B), 512 (PM6681)Sensitivity:

10 mV rms to 12V rms, 70 to 900 MHz15 mV rms to 12V rms, 900 to 1100 MHz40 mV rms to 12V rms, 1100 to 1300 MHzAmplitude Modulation:DC to 0.1 MH: Up to 94% depth0.1 to 6 MHz: Up to 85% depthMinimum signal must exceed Input SensitivityImpedance: 50 nominal, AC coupled, VSWR < 2:1Max. Voltage without Damage: 12V rms pin diode protected

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Connector: BNC

Input C (PM 9624) Frequency Range: 100 MHz to 2.7 GHzPre-Scaler Factor: 16 (PM6680B), 32 (PM6681)Sensitivity: 20 mV rms to 12V rms, 100 to 300 MHz

10 mV rms to 12V rms, 0.3 GHz to 2.5 GHz20 mV rms to 12V rms, 2.5 GHz to 2.7 GHzAmplitude Modulation: DC to 0.1 MHz: Up to 94% depth0.1 to 6 MHz: Up to 85% depthMinimum signal must exceed Input SensitivityImpedance: 50 nominal, ac coupled, VSWR < 2.5:1Max. Voltage without Damage: 12V rms pin diode protectedConnector: Type N Female

Input C (PM9625B)

Frequency Range: 150 MHz to 4.2 GHzPre-Scaler Factor: 32 (PM6680B), 64 (PM6681)Sensitivity:

20 mV rms to 1V rms, 150 to 300 MHz10 mV rms to 1V rms, 0.3 GHz to 2.2 GHz15 mV rms to 1V rms, 2.2 GHz to 3.5 GHz25 mV rms to 1V rms, 3.5 GHz to 4.2 GHz50 mV rms to 1V rms, 4.2 GHz to 4.5 GHzAmplitude Modulation: DC to 0.1 MHz: Up to 94% depth0.1 to 6 MHz Up to 85% depthMinimum signal must exceed Input SensitivityImpedance: 50 nominal, AC coupled, VSWR < 2.5:1Damage Level: 12V rms pin diode protectedConnector: Type N Female

Rear Panel Inputs And Outputs ExternalReference Input D

Range: (PM6681): 1,2,5 or 10 MHz, > 200 mV signal.(PM6680B): 10 MHz, > 500 mV signal.

Arming Input E Most measurement functions can be performed via arming input.Range: (PM 6681): DC to 100 MHz(PM 6680B): DC to 50 MHzSlew Rate: > 2V/sTrigger Level: TTL, 1.4V nominalTrigger Slope: Positive or Negative

Damage Level: 25V peak ReferenceOutput G

Frequency: 10 MHz, Sine WaveOutput: > 0.5 V rms into 50 load, > 0.7 V rms into hi impedance load. ACcoupled

Gate OpenOutput H

Ouput Level: Closed: < 0.4 VOpen: > 1.4 V into 50 Internal Delay: 20 ns

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Trigger LevelOutputs

Output Level: (PM6681): Trigger Level/Attn Setting(PM6680B): Trigger Level/(10 * Attn Setting)Impedance: (PM6681) 100 (PM6680B) 3 k

ProbeCompensationOutput

Buffered outputs for input A & B signals. Best used for adjustment of probes tobest pulse response for the combination of probe and counter input.

Analog output (Included with GPIB option only)0 to 4.98 V in 20 mV steps, derived from three consecutive digits selected fromthe measurement result.

Auxiliary Functions Trigger Hold-Off Time Delay Range:

(PM 6681): 60 ns to 1.34s, 10 ns resolution(PM 6680B): 200 ns to 1.6s, 100 ns resolution

Event Delay Range B: (PM 6681): 2 to 2 24 -1, max. 100 MHz(PM 6680B): 2 to 2 24 -1, max. 20 MHz

External Arming External signal on input E can be used to inhibit start and/or stop triggering.

Arming Delay Arming can be delayed with respect to the external arming trigger event untileither the preset arming time has elapsed or the preset number of triggerevents on B has occurred.Time Delay Range B & E: 200 ns to 1.6 s, 100 ns resolutionEvent Delay Range B: 2 to 2 24 -1, negative slope (up to 20 MHz)

Statistics

Min, Max, Mean and Standard Deviation. Statistics may be applied to allmeasurement functions with the exception of Manual Totalize.

Sample Size: (PM 6681): 1 to 2 x 10 -9 samples(PM 6680B): 1 to 65535 samples

Mathematics Mathematics may be applied to all measuring functions.Functions: (K*X+L)/M or (K/X+l)/M where: X is the current reading and K,L,and M are selectable constants.

Other Functions Measuring time (PM 6681): Single cycle, 80, 160, 320, 640, 1280 ns and 20 s to 20s (or to

400s for some functions)

(PM 6680B): Single cycle, 0.8, 1.6, 3.2, 6.4, 12.8 s and 50 s to 20s (or to400s for some functions)

Display Hold Freezes measuring result, until a new measurement is initiated via Restart

Settings 20 instrument settings can be saved and recalled from internal non-volatilememory. 10 can be user protected.

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Auxiliary Menu Gives access to additional functions

Display 10-digit LCD with high-luminance backlight

GPIB Interface Programmable Functions: All front panel accessibleInterface Functions: SH1, AH1, T6, L4, SR1, RL1, DC1, DT1, E2Time Stamping (PM 6681): 125 ns resolution

MeasurementRate *

Via GPIB: (PM6681): 250 readings/s(PM6680B): 125 readings/sTo Internal Memory: (PM6681): 8k readings/s(PM6680B): 2k readings/sInternal Memory Size: (PM 6681): * Up to 6100 readings(PM 6680B): * Up to 2600 readingsData Output: ASCII, IEEE double precision floating point

Software:

TimeViewTM

Time & FrequencyAnalysis Software

TimeView runs on an IBM PC/AT or compatible with VGA/EGA monitor.

Data CaptureModes andMeasurement Rate

Free Running Measurement: (PM6681) 8k readings/s(PM6680B) 2k readings/sRepetitive Sampling: Up to 10 MHzContinuous Single-Period: PM 6681: Up to 40k readings/s (200 ns resolution)PM 6680B: N/AWaveform Capture: Available with PM6681Data Analysis Features: Measurement data vs. time, FFT Graph, Root AllanVariance, Smoothing function, Zoom function, Cursor measurements,Distribution Histogram, Setup and Measurement, Data Archive and Printing

*Depending on measurement function and internal data format

General Specifications EnvironmentalData

Operating Temp: (PM 6681): 0C to +50C(PM 6680B): 0C to +55CFan option is required when: 1.Ambient temp. >50C2. Internal rack temp. >45; while mounted with no free air convection spaceand oven oscillator PM 9690 or PM 9691 is installed

Storage Temperature: -40C to +70CVibration: 3G at 55 Hz per MIL-T-28800DShock: Half-sine 40G per MIL-T-28800D. Bench handling. Shipping container.Reliability: MTBF 30 000 h (calculated)Safety: According to CE-regulation 73/23 EN61010-1 CAT II, Pollution Degree 2EMC: According to CE regulation 89/336:Emission according to EN 50081-1, EN 55011Immunity according to EN 50082-1, inclusive IEC 801-2, -3, -4

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PowerRequirements

90V rms to 265V rms, 45 Hz to 440 Hz, 35W

Mechanical Data Width: 315 mm (12.4 in)Height: 86 mm (3.4 in)Depth: 395 mm (15.6 in)

Weight: Net 4 kg (8.5 lb),Shipping 7 kg (15 lb)