page_title: Routing (electronic design automation)
section_title: Types of routers
hierarchical_section_title: Routing (electronic design automation) / Types of routers
caption_attribution_description: English: This picture shows (left) a printed circuit board (PCB) layout, created on a computer and (right) the manufactured board, populated with parts. Both through-hole and surface mounts components have been used; the board is double-sided, with through-hole plating, green solder resist, white solder paste (visible on unsoldered holes, such as the four corner mounting holes and the nine holes down the right hand side of the board) and white silkscreen printing. Italiano: Progetto di un circuito stampato a sinistra e realizzazione a destra. Deutsch: Links das im CAD erstellte Layout einer Leiterplatte, in dem die verschiedenen Lagen mit unterschiedlichen Farben dargestellt sind. Rechts die daraus hergestellte und mit Bauelementen bestückte Leiterplatte. Español: A la izquierda la imagen de la PCB diseñada por ordenador y a la derecha la PCB manufacturada y montada. Svenska: Datordesign av ett mönsterkort (vänster) och det färdiga kretskortet (höger) 中文: 印刷電路板 Magyar: A baloldalon egy NYÁK CAD program segítségével tervezett rajza, a jobboldalon pedig a rajznak megelelően elkészített panel látható. Bahasa Indonesia: Foto dari desain sirkuit dan realisasinya 한국어: 컴퓨터로 설계된 인쇄회로기판 (왼쪽) 및 기판과 부품이식된 실장 (오른쪽). 기판은 홀로 통하는 도금, 녹색 땝납 저항, 흰 땝납 페이스트, 흰 실크스크린 프린트가 있는, 양면이다. 양쪽 표면 실장과 홀로 통하는 부품은 사용되었다.
context_page_description: In electronic design, wire routing, commonly called simply routing, is a step in the design of printed circuit boards and integrated circuits. It builds on a preceding step, called placement, which determines the location of each active element of an IC or component on a PCB. After placement, the routing step adds wires needed to properly connect the placed components while obeying all design rules for the IC. Together, the placement and routing steps of IC design are known as place and route.
  The task of all routers is the same. They are given some pre-existing polygons consisting of pins on cells, and optionally some pre-existing wiring called preroutes. Each of these polygons are associated with a net, usually by name or number. The primary task of the router is to create geometries such that all terminals assigned to the same net are connected, no terminals assigned to different nets are connected, and all design rules are obeyed. A router can fail by not connecting terminals that should be connected, by mistakenly connecting two terminals that should not be connected, or by creating a design rule violation.
context_section_description: The earliest types of EDA routers were "manual routers"—the drafter clicked a mouse on the endpoint of each line segment of each net.
  Modern PCB design software typically provides "interactive routers"—the drafter selects a pad and clicks a few places to give the EDA tool an idea of where to go, and the EDA tool tries to place wires as close to that path as possible without violating design rule checking (DRC). Some more advanced interactive routers have "push and shove" (aka "shove-aside" or "automoving") features in an interactive router; the EDA tool pushes other nets out of the way, if possible, in order to place a new wire where the drafter wants it and still avoid violating DRC.
  Modern PCB design software also typically provides "autorouters" that route all remaining unrouted connections without human intervention.
  The main types of autorouters are:
  Maze router
  Lee router
  Hadlock router
  Flood router
  Line-probe router
  Mikami–Tahuchi router
  Hightower router
  Pattern router
  Channel router
  Switchbox router
  River router
  Spine and stitch router
  Gridless router
  Area router
  Graph theory-based router
  Bloodhound router (CADSTAR by Racal-Redac / Zuken)
  Specctra (aka Allegro PCB Router) (gridless since version 10)
  Topological router
  FreeStyle Router (aka SpeedWay, a DOS-based autorouter for P-CAD)
  TopoR (a Windows-based autorouter, also used in Eremex's Delta Design)
  Toporouter (Anthony Blake's open-source router in PCB of the gEDA suite)
  TopRouter (the topological pre-router in CadSoft/Autodesk's EAGLE 7.0 and higher)
  SimplifyPCB (a topological router with a focus on bundle routing with hand-routing results)
caption: A PCB as a design on a computer (left) and realized as a board assembly populated with components (right). The board is double sided, with through-hole plating, green solder resist and a white legend. Both surface mount and through-hole components have been used.
exif: {}