A slice or flat disk, either of semiconductor material or of such a material deposited on a substrate, in which circuits or devices are simultaneously processed and subsequently separated into chips if there is more than one device.

A signal indicating that the device addressed by the central processing unit has not yet completed its data transfer. (Ref. IEC 824.)

See "write enable".

The adhesion or weld of a thin wire, usually aluminum, to a package bonding surface, usually a plated leadframe post or finger, using an ultrasonic wire-bonding process. The wedge bond includes the compressed (ultrasonically bonded) area of the wire and the underlying bonding surface. For bonding to an aluminum alloy die bond pad, there is no wedge bond-bond pad intermetallic because the two materials are of the same composition; the two materials are recrystallized together by the ultrasonic energy of the welding process.

A spontaneous columnar or cylindrical filament, usually of monocrystalline metal, emanating from the surface of a finish.

NOTE Whiskers are not to be confused with dendrites, which are fern-like growths on the surface of a material, formed as a result of electromigration of an ionic species or during solidification.

Measurable changes in whisker length and/or whisker density after exposure to a whisker test condition for a certain duration or number of cycles.

A piece of metal of specified size and shape that is plated or dipped with a tin finish for the purpose of measuring the propensity for whisker formation and growth.

A hole formed by etching through an oxide or insulating layer on a semiconductor for the purpose of diffusion into or deposition onto a selected area of the semiconductor.

The total amount of interconnect of a net (specified in units of either length or capacitance).

A device that has a parallel data interface of 16 bits or more (usually in multiples of 16 bits), possibly with additional bits appended to provide parity or error-detection capability.

See "write protect".

The corruption of data in one location caused by the writing of data at another location.

The output signal used to reflect the status of the write-protect switch on the memory card. If the memory card write-protect switch is present, this signal will be asserted by the card when the switch is enabled, and deasserted when the switch is disabled. If the memory card has no write-protect switch, the card will connect this line to ground or V_CC, depending on the condition of the card memory. If the card can always be written, the pin will be connected to V_SS. If the card is permanently write-protected, the pin will be connected to V_CC.

See "write transfer".

A 4-arm bridge forming a diamond, all of whose arms are predominantly resistive, with three resistors of known values in three of the arms and the unknown resistor in the fourth.

NOTE 1    A voltage source, e.g., a battery, is connected across two opposite points of the diamond and a current-detecting instrument (e.g., a galvanometer) is connected across the other two points. The values of one or two of the known resistors are varied until no current flows through the galvanometer. The bridge is then balanced and the value of the unknown resistor can be calculated in terms of the other three.