Eric M Berman

US Patent:

54559375, Oct 3, 1995

Filed:

Jun 30, 1994

Appl. No.:

8/268673

Inventors:

Eric Berman - Hicksville NY
Greg Italiano - Hicksville NY
Ajay Padgaonkar - Sugarland TX
Ray Allen - Mesa AZ

Assignee:

Microchip Technology, Inc. - Chandler AZ

International Classification:

G11C 700
G01R 3128

US Classification:

395500

Abstract:

A microcontroller fabricated on a semiconductor chip has an on-chip EPROM program memory with programmable EPROM configuration fuses located in a limited number of addresses of the on-chip program memory, the condition of each of EPROM fuse being defined as blown or not blown according to the value of the bit stored in the respective address of the on-chip program memory. The operating modes of the microcontroller are configurable by appropriately programming at least some of the EPROM fuses. Testing of the microcontroller in at least some of the operating modes is achieved by using latches outside the program memory to emulate the EPROM fuses, while suppressing the capability to set the condition of the EPROM fuses during the testing. Upon completion of the testing, control of the operating modes of the microcontroller is returned to the EPROM fuses, and the latches are precluded from further emulating the EPROM fuses.

US Patent:

54041724, Apr 4, 1995

Filed:

Mar 2, 1992

Appl. No.:

7/845734

Inventors:

Eric B. Berman - Commack NY
William B. H. Jorden - Malverne NY
Philip R. McLaughlin - Huntington NY
William Posner - Plainview NY

Assignee:

EEG Enterprises, Inc. - Farmingdale NY
Extratek, Inc. - Hicksville NY

International Classification:

H04N 7087

US Classification:

348465

Abstract:

A data and synchronization extraction circuit for processing composite video signals containing closed captioning data is disclosed. A dual mode voltage clamp is realized in CMOS technology which includes temperature compensated current sources in the form of complementary current mirrors. A modified version of such current sources is also disclosed which permits trimming of the current after manufacture and packaging. Sync pulses are separated by doubling the amplitude of a composite video signal with an amplifier and comparing the amplified signal with a back porch level derived by a sample-and-hold device. Frequency and phase synchronization is accomplished by a combination of a frequency lock loop and a phase lock loop working in concert to generate a control voltage for a voltage controlled oscillator in a flywheel mode. The voltage controlled oscillator provides a clean source of timing information for the circuit. The effects of impulse noise in the detection of vertical retrace pulses are eliminated by the use of digital counting circuits which count the requisite number of horizontal synchronization pluses which occur between valid retrace pulse and which block pluses that appear at other times.

US Patent:

54468647, Aug 29, 1995

Filed:

Mar 7, 1994

Appl. No.:

8/207886

Inventors:

Martin Burghardt - Oberneuching, DE
Eric Berman - Hicksville NY
Ajay Padgaonkar - Sugarland TX
Ray Allen - Mesa AZ

Assignee:

Microchip Technology, Inc. - Chandler AZ

International Classification:

G06F 1214

US Classification:

395427

Abstract:

A microcontroller fabricated on a semiconductor chip has an on-chip EPROM program memory. The microcontroller is selectively configurable to operate in any one of a plurality of predetermined operating modes, including at least one secure microcontroller mode. A plurality of EPROM configuration fuses used for configuring the microcontroller and protecting its program memory from read, verify or write through any instruction initiated from other than a predetermined secure area of the chip, are mapped into the on-chip EPROM program memory as bits in respective address locations thereof. The value of a bit representing any one of said fuses is effective to determine the condition of the respective fuse. That condition is observed by reading the value of the respective bit for that fuse stored in the EPROM program memory. The chip security is enabled by configuring the microcontroller in a code protected mode by programming the bits representing the desired fuses in the EPROM program memory to effectively blow or erase each fuse according to the desired configuration.