The Tektronix TDS640A is a professional-grade 4-channel digital oscilloscope designed for high-speed, multi-channel waveform capture. Part of the legacy TDS series, it features an analog bandwidth of 500 MHz and provides a real-time sample rate of 2 GS/s simultaneously on all four channels. Equipped with an 8-bit ADC, a bright NuColor color display, a built-in floppy drive, and diverse interface connectivity, the TDS640A is tailored for demanding electronic design, debug, and characterization tasks.

Specifications

General

ParameterValue
Display7-inch monochrome CRT, 640 x 480 pixels
Warm-Up Time20 minutes
CoolingForced-air circulation
EMC ComplianceMeets FCC Part 15 Class A, EN 55011 Class A

Physical

ParameterValue
Power Supply90 to 250 V AC, 45 to 440 Hz, 300 W maximum
Operating Temperature0 to +50 °C
Dimensions (W×H×D)445 mm × 193 mm × 434 mm
Weight14.1 kg

Vertical System (Analog Channels)

ParameterValue
Number of Channels4
Analog Bandwidth (-3 dB)500 MHz
Rise Time≤ 700 ps (calculated)
Vertical Resolution (ADC Bits)8-Bit
Vertical Sensitivity Range1 mV/div to 10 V/div
DC Gain Accuracy±1.5%
Input Impedance50 Ω
Input CouplingDC, GND
Maximum Input Voltage5 V RMS (with peaks ≤ ±25 V)
Hardware Bandwidth Limits20 MHz, 100 MHz

Horizontal System (Timebase)

ParameterValue
Timebase Range500 ps/div to 5 s/div
Timebase Accuracy±100 ppm (0.01%)
Standard Record Length2,000 points per channel

Acquisition System

ParameterValue
Real-Time Sample Rate (All Channels)2 GS/s (simultaneously on all 4 channels)
Acquisition ModesSample, Envelope, Average

Trigger System

ParameterValue
Trigger SourcesCH1, CH2, CH3, CH4, AC Line, Auxiliary
Trigger ModesAuto, Normal, Single
Trigger CouplingDC, AC, Low Frequency Reject, High Frequency Reject, Noise Reject
Trigger TypesEdge, Pulse (Glitch, Width, Runt, Setup/Hold, Pattern, State)
Auxiliary Trigger InputYes
Trigger Level Range±12 divisions from center of screen (internal)
Trigger Sensitivity (Internal)0.35 div from DC to 50 MHz, 1.0 div at 500 MHz
Trigger Sensitivity (External)40 mV from DC to 50 MHz, 150 mV at 500 MHz
Trigger Holdoff Range250 ns to 12 s
Auxiliary Trigger Input Impedance1 MΩ

Display Characteristics

ParameterValue
Display TypeMonochrome CRT
Display Resolution640 × 480 pixels
Display Size7 in. (diagonal)
Waveform Display StylesVectors, Dots, Infinite Persistence, Variable Persistence
GraticulesFull, Grid, Crosshair, Frame

Measurements & Analysis

ParameterValue
Automatic Measurements25 fully automated measurements (including Amplitude, Period, Frequency, Rise/Fall Time, Width)
Cursor MeasurementsVolts, Time, Paired
Waveform Processing (Math)Add, Subtract, Multiply, Divide, Invert
Advanced Waveform DSPOptional (Option 2F)
Limit Testing / Mask TestingWaveform Pass/Fail Template Testing
Automatic Measurements Count25 automatic measurements

Input / Output Ports & Interfaces

ParameterValue
GPIB InterfaceIEEE-488.2 standard interface
RS-232 Serial PortOptional (Option 13)
Centronics Parallel PortOptional (Option 13)
VGA Output15-pin D-sub connector for external monitor
Probe Compensation Output0.5 V into ≥1 MΩ, 1 kHz

Power Requirements

ParameterValue
Line Voltage Range90 to 250 V AC
Line Frequency Range45 to 440 Hz
Power Consumption300 W maximum

Physical Characteristics

ParameterValue
Height193 mm (7.6 in.) with feet
Width445 mm (17.5 in.) with handle
Depth434 mm (17.1 in.) with cover
Net Weight14.1 kg (31 lbs.)
Shipping Weight20.0 kg (44 lbs.)

Environmental & Reliability

ParameterValue
Non-Operating Temperature-40 to +75 °C
Operating HumidityUp to 95% RH at or below +30 °C
Operating AltitudeUp to 4,570 m (15,000 ft.)
Non-Operating AltitudeUp to 12,190 m (40,000 ft.)

Standards & Compliance

ParameterValue
Safety CertificationsUL 1244, CSA C22.2, EN61010-1

Options & Accessories

ParameterValue
Memory Expansion OptionOption 1M increases record length to 120,000 points per channel
Rackmount OptionOption 1R (Rackmount Kit)

Vertical System

ParameterValue
Input Impedance Tolerance50 Ω ± 1%
Channel-to-Channel Isolation≥ 100:1 at 100 MHz, ≥ 30:1 at 500 MHz
Number of Digitizers4 (one per channel)
Offset Range±1 V (1 mV to 99.5 mV/div), ±10 V (100 mV to 995 mV/div), ±100 V (1 V to 10 V/div)

Horizontal System

ParameterValue
Delay Time Range (Pre-Trigger)0% to 100% of record
Delay Time Range (Post-Trigger)0 to 250,000 divisions

Environmental

ParameterValue
Operating Shock15 g (half-sine), 11 ms duration
Operating Vibration0.31 g RMS, 5 Hz to 500 Hz
Non-Operating Vibration2.46 g RMS, 5 Hz to 500 Hz

Display

ParameterValue
CRT Phosphor TypeP31 Green

Storage

ParameterValue
Reference Waveform Storage4 internal 2000-point waveforms

Hardware Options

ParameterValue
Option 05 Video TriggeringAdds NTSC, PAL, SECAM, and custom video triggering
Option 13 Interface ExpansionAdds RS-232 serial and Centronics parallel interfaces
Option 1F Storage ExpansionAdds 3.5-inch 1.44 MB floppy disk drive
Option 2F Math ExpansionAdds Advanced DSP Math (FFT, integration, differentiation)
Option 1K CartK212 Instrument Cart compatibility

Technology

Digital Storage Oscilloscope (DSO)

Applications

High-speed digital design, debugging, power supply characterization, and general electronics testing