The HP / Agilent / Keysight 1661C is a high-performance benchtop logic analyzer designed for debugging and validating complex digital systems. It provides 102 state and timing channels, a state speed of up to 100 MHz, and a timing speed of up to 500 MHz in half-channel mode. Equipped with built-in HP-IB and RS-232C interfaces as well as a 3.5-inch floppy disk drive, it is a robust and classic troubleshooting tool for legacy and embedded hardware designs.

Specifications

General

ParameterValue
InterfacesHP-IB (GPIB), RS-232C
Display9-inch monochrome CRT (640 × 350 resolution)

Physical

ParameterValue
Power Supply115/230 V AC (-22% to +10%), 48-66 Hz, 200 W maximum
Operating Temperature0 to 55 °C
Dimensions (W×H×D)425 mm × 188 mm × 432 mm
Weight11.8 kg

Performance

ParameterValue
Number of State and Timing Channels102 channels
Maximum State Analysis Rate100 MHz
Maximum Conventional Timing Rate (Full Channel)250 MHz
Maximum Conventional Timing Rate (Half Channel)500 MHz
Maximum Transitional Timing Rate (Full Channel)125 MHz
Maximum Transitional Timing Rate (Half Channel)250 MHz
Memory Depth per Channel (Full Channel)4,096 samples
Memory Depth per Channel (Half Channel)8,192 samples
Trigger Sequence Levels12 levels
Trigger Pattern Recognizers10
Trigger Range Recognizers2
Trigger Edge/Glitch Recognizers2
Channel-to-Channel Skew< 2 ns (typical)

System Architecture

ParameterValue
Storage Type3.5-inch Floppy Disk Drive (FDD), 1.44 MB DOS format

Inputs & Outputs

ParameterValue
Probe Input Resistance100 kΩ
Probe Input Capacitanceapproximately 8 pF
External Trigger InputBNC, TTL compatible
External Trigger OutputBNC, TTL compatible

Environmental

ParameterValue
Maximum Operating Altitude4,600 m (15,000 ft)
Storage Temperature Range-40 to +75 °C

Input Probes

ParameterValue
Threshold Range-6.0 V to +6.0 V in 50 mV increments
Threshold Accuracy±(100 mV + 3% of threshold setting)
Minimum Input Voltage Swing500 mV peak-to-peak
Maximum Input Voltage±40 V peak

State Analysis

ParameterValue
Minimum Clock Pulse Width3.5 ns
Setup/Hold Time3.5/0 ns or 0/3.5 ns (user selectable, single clock, single edge)
Number of State Clocks6

Timing Analysis

ParameterValue
Minimum Glitch Width3.5 ns

Data Storage

ParameterValue
File FormatsMS-DOS, LIF
Floppy Drive Format SupportDOS (1.44 MB, 720 KB) / LIF (1.44 MB, 610 KB)

Tagging & Measurements

ParameterValue
Time Tag Resolution8 ns or 0.1% (whichever is greater)
Maximum Time Tag Duration34.4 seconds
State Tag Counter Size24-bit
Maximum State Tag Count1.67 × 10^7

Probing

ParameterValue
Input Dynamic Range±10 V
Preset ThresholdsTTL, CMOS, ECL

Power Requirements

ParameterValue
AC Input Voltage Range90 V to 264 V AC (auto-ranging)
AC Line Frequency48 Hz to 66 Hz
Maximum Power Consumption200 W

Technology

Logic Analyzer

Applications

Digital system design, hardware troubleshooting, embedded systems testing