Circuit for in-system programming of memory device
US6404174B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 27, 2000 |
| Grant date | Jun 11, 2002 |
| Priority date | — |
| Expiry date | Oct 27, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M1/0045
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A programming circuit is coupled to an input/output pin of a device and is operative to generate a selected one of a plurality of electrical stimuli, such as a programming voltage, high and low logic levels, and a high impedance output, to the device in selected electrical state, without affecting normal device operation. The programming circuit includes a switchmode power converter, a linear regulator, and a control circuit. The programming voltage is generated by the switchmode power converter only when required for programming the device. The linear regulator includes a transistor having its collector-emitter path coupled in circuit with the switchmode converter and an output node, as well as to a voltage divider network. The voltage divider network is coupled to the control input of a precision shunt regulator device, which supplies a base reference for the transistor to establish the value of a voltage to be applied provided from the output node to the device. The base of the linear regulator's transistor is also controllably coupled to ground through the collector-emitter path of a steering transistor of the control circuit. The regulator's output node is also controllably co…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.