OrCAD

OrCAD Systems Corporation
Company type	Public (before acquisition)
Industry	Electronic design automation software
Founded	1985 in Hillsboro, Oregon, United States
Founder	John Durbetaki, Ken Seymour, Keith Seymour
Defunct	1999 (acquired)
Fate	Acquired by Cadence Design Systems in 1999; merged with Cadence Allegro in 2005
Headquarters	Hillsboro, United States
Area served	Worldwide
Key people	John Durbetaki (founder, former CEO), Michael Bosworth (CEO after 1991), Peter LoCascio (sales development)
Products	OrCAD suite (Capture, PSpice, PCB Designer Professional)
Parent	Cadence Design Systems (from 1999)
Website	www.orcad.com

OrCAD Systems Corporation was a software firm specializing in the development of OrCAD, a proprietary suite of electronic design automation (EDA) tools. This suite was widely utilized by electronic design engineers and technicians for schematic creation, mixed-signal simulations, and generating manufacturing documentation for printed circuit boards (PCBs). In 1999, Cadence Design Systems acquired OrCAD, subsequently merging it with Cadence Allegro in 2005.

Company

Established in 1985 by John Durbetaki alongside brothers Ken and Keith Seymour in Hillsboro, Oregon, OrCAD provided desktop EDA software solutions. The company’s name is derived from a blend of Oregon and CAD. Durbetaki, previously employed at Intel, initially created a schematic capture tool designed for PC expansion chassis but later redirected efforts toward affordable PC-based CAD software. Their inaugural product, SDT (Schematic Design Tools) for DOS, was introduced at the end of 1985.

In 1986, Peter LoCascio joined the team to lead sales development, coinciding with co-founder Ken Seymour’s departure. Following SDT, the company released the digital simulator VST (Verification and Simulation Tools) along with PCB layout applications. Over time, their offerings evolved into Windows-compatible tools supporting FPGA and CPLD designs. Durbetaki stepped down as CEO and head of R&D in 1991, with Michael Bosworth succeeding him.

The acquisition of Massteck Ltd. in 1995 brought OrCAD a PCB layout tool and autorouter capabilities; simultaneously, they obtained Intelligent Systems Japan KK, their Japanese distributor. The company transitioned to public ownership in 1996.

Between 1997 and 1998, OrCAD merged with MicroSim Corporation, recognized for PC-based analog and mixed-signal simulation software (PSpice), although this merger did not meet performance expectations.

On July 16, 1999, Cadence Design Systems purchased OrCAD for $121 million.

OrCAD Layout was eventually superseded by PCB Designer (Allegro PCB Designer). The latest version of OrCAD CIS schematic capture software maintains an integrated circuit database updated through downloads from manufacturers such as Analog Devices. STMicroelectronics licenses PSpice models for their power and logic semiconductor products. Additionally, Intel supplies reference PCBs created using Cadence PCB Tools in OrCAD Capture format for embedded systems and personal computing devices.

Products

The OrCAD suite offers comprehensive solutions for PCB design and analysis, including a schematic editor (Capture), an analog/mixed-signal circuit simulation tool (PSpice), and a professional-grade PCB layout application (PCB Designer Professional).

OrCAD Capture

OrCAD Capture serves as the schematic capture module within the OrCAD suite.

Unlike NI Multisim, Capture does not incorporate internal simulation capabilities but exports netlist data to OrCAD EE for simulation purposes. It also supports exporting hardware description languages such as Verilog or VHDL and can generate netlists compatible with PCB layout tools like OrCAD Layout and Allegro.

Capture features a component information system (CIS) that associates package footprints or simulation data directly with schematic symbols. It offers support for Tcl/Tk scripting to enable customization and automation within the graphical user interface.

Through the OrCAD Capture Marketplace, users can exchange and commercialize add-ons that enhance design functionality. Capture also connects to databases adhering to Microsoft’s ODBC standard, allowing seamless integration with MRP, ERP, or PDM systems during component selection processes.

OrCAD PSpice

OrCAD EE PSpice is a SPICE-derived simulator designed for verifying analog and mixed-signal circuits. It primarily models circuits created in OrCAD Capture and can optionally interface with MATLAB/Simulink through the Simulink to PSpice Interface (SLPS). Together, Capture and PSpice Designer provide a comprehensive environment for schematic design and circuit simulation.

Initially developed by MicroSim in 1984 and later acquired by OrCAD in 1998, PSpice Designer is available in two variants: PSpice Designer and PSpice Designer Plus. The Plus edition incorporates the PSpice Advanced Analysis module, which enhances simulation capabilities and contributes to improved design robustness and yield.

The Advanced Analysis suite offers tools such as Sensitivity, Monte Carlo, Smoke (Stress), Optimizer, and Parametric Plotter analyses, enabling detailed evaluation of circuit behavior. Integration with SLPS facilitates co-simulation for system-level validation.

Circuit descriptions are processed through PSpice files, generating graphical simulation outputs within the OrCAD EE platform. OrCAD EE expands upon the core PSpice functionality by including features like automatic optimization, waveform capture, advanced analysis, curve fitting, and post-simulation data processing.

The software package contains an extensive library featuring approximately 33,000 device models for analog and mixed-signal components, alongside a model editor, support for parameterized devices, auto-convergence mechanisms, checkpoint restart capability, multiple solver options, and a magnetic component editor.

History

SPICE was developed at the University of California, Berkeley during the early 1970s, with SPICE 2 enhancing CAD support by the mid-1970s. In January 1984, PSpice was introduced as the first Berkeley SPICE version compatible with IBM PCs. It later incorporated a waveform viewer and analyzer named Probe. Subsequent versions expanded support to platforms including DEC/VAX minicomputers, Sun workstations, Apple Macintosh systems, and Microsoft Windows. The 1988 release of version 3.06 included a "Student Version" that restricted circuits to ten transistors, fostering educational use by simplifying electronic component and circuit study.

Analyses

PSpice executes simulations driven by source definitions and control instructions, offering:

DC Analysis — calculates steady-state voltages at nodes and branch currents for DC sources over parameter ranges using Linear sweep, Logarithmic sweep, or List sweep methods.
Transient Analysis — evaluates time-dependent nodal voltages and branch currents for sources such as sinusoidal or switched DC over specified time periods.
AC Analysis — determines small-signal frequency responses by calculating magnitude and phase of nodal voltages and branch currents across frequency sweeps.

The operating temperature can be adjusted; default node parameters are set assuming 27 °C ambient conditions.

PSpice User Community

An online platform supports users with resources including datasheets, application notes, tutorials, instructional videos, as well as details on regional training sessions and webinars. This portal also provides access to an extensive repository of over 33,000 PSpice models available through the PSpice Lite Download.

PSpice Lite delivers full software capabilities but restricts circuit size and complexity limits, making it well suited for student use.

OrCAD PCB Designer

OrCAD PCB Designer is a printed circuit board design software included in the OrCAD suite, equipped with automation features for PCB layout, board-level verification, and design rule validation (DRC).

Users can develop designs either manually or by utilizing the built-in Auto-Router, which accommodates curved routing paths, geometric figures, and ground planes. It offers tight integration with OrCAD Capture through the component information system (CIS), connecting schematic symbols directly to their corresponding PCB footprints.

PCB Designer file formats

As of 2019, the primary supported file extensions are:

File extension	Description
.brd	PCB board design file
.mdd	Module placement replicate file
.dra and .psm	Package symbol files
.dra and .bsm	Mechanical symbol files
.dra and .osm	Format symbol files
.dra and .ssm	Shape symbol files
.dra and .fsm	Flash symbol files
.pad	Padstack files for vias
pstxchip.dat, pstxnet.dat, pstxprt.dat	Netlist data files
pstdedb.cdsz	Netlist with constraints manager activated
.dsn	Schematic design file
.opj	Schematic project file (reproducible)
.olb	Schematic library file

OrCAD Library Builder

This tool facilitates library creation adhering to IPC-7351 guidelines for generating symbols and footprints. It also enables automated STEP file creation from footprint data, improving compatibility with mechanical CAD systems.

External links

, OrCAD
AiPCBA