Investigating packaging effects on bandgap references

This thesis investigates packaging effects on precision bandgap voltage references used in LTC switching regulators. Packaging stress causes a mean offset and room temperature distribution widening of the bandgap reference output voltage, as well as inconsistent temperature characteristics. Bandgap references with and without a proprietary stress-relief mechanism were compared to determine the impact of packaging stress on reference performance. References without stress-relief showed a mean offset of -2.3mV and spread of 10mV, while references with stress-relief showed a mean offset of -2.0mV and spread of 3.6mV. References with stress relief exhibited more consistent temperature coefficients than references without stress relief. A test chip was fabricated to allow measurement of VBE and AVBE within the bandgap reference. Parts with stress-relief showed tighter VBE and AVBE distributions, as well as more favorable temperature characteristics. The experiments in this thesis show that stress-relief is effective at improving bandgap reference performance.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• Palakodety, Ravi (Ravi Kiran)

Advisor dc:contributor.advisor

• Tick Houk and Charles Sodini.

• Electrical Engineering and Computer Science.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/41665

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/41665