Bilateral zener trim
US4451839A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 19, 1983 |
| Grant date | May 29, 1984 |
| Priority date | — |
| Expiry date | Apr 19, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D84/221
Abstract
In an integrated circuit, back to back zener diodes are connected between circuit pads and each zener diode shunts a resistor in a series string. When a suitable pulse is applied to the pair, the back biased diode will be selectively shorted. Thus, the pulse polarity will determine which diode will short and which resistor will be bypassed. In this manner a pair of pads can be used to selectively short out either one or both of a pair of diodes and a trimming section can be created using only half of the pads required in the case where each zener is contacted separately. The invention is directed to a structure in which the forward biased zener diode is protected so that only the reverse biased diode shorts out when the pulse is applied.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.