公开(公告)号：DE69727356D1

公开(公告)日：2004-03-04

申请号：DE69727356

申请日：1997-05-21

Applicant: MICROCHIP TECH INC

Inventor： HULL L ,  BINGHAM GREGORY ,  FINK SCOTT ,  ROGERS CLARK ,  ELLISON SCOTT

IPC: G06F1/24 ,  G06F15/78 ,  H03L7/00

Abstract: The present invention relates to a microcontroller that may be configured to operate without the accompaniment of any external components. The microcontroller can function in a proper manner from the application of only power and signal lines with no external components required. The microcontroller has integrated internal reset and oscillator circuitry into the microcontroller. The microcontroller has also integrated simple external components such as current limiting resistors and pull up and pull down resistor into the microcontroller in order to avoid application specific external components.

公开(公告)号：DE69616266T2

公开(公告)日：2002-07-04

申请号：DE69616266

申请日：1996-07-17

Applicant: MICROCHIP TECH INC

Inventor： YACH L ,  HULL L

IPC: G11C5/14 ,  H02H3/24 ,  H02J1/00 ,  H03K17/14 ,  H03K17/22 ,  G11C16/06

Abstract: A power-on reset (10) for resetting electronic circuitry to be monitored has been provided. The power-on reset circuit includes a trip point generator (12) including the worst case component (the component that requires the greatest power supply voltage to operate) within the electronic circuitry for setting the threshold voltage for taking the electronic circuitry out of reset such that if the worst case component is operative, it is guaranteed that all components are operative and, thus, the electronic circuitry can be taken out of reset. Moreover, because the threshold voltage is based upon the worst case component of the electronic circuitry, the threshold voltage of the trip point generator will adequately track the electronic circuitry over normal process and temperature variations. Additionally, the power-on reset circuit includes a noise filter (34) for placing the electronic circuitry back into reset if variations within the power supply voltage cause the power supply voltage level to fall below a predetermined threshold for at least a minimum period of time.

公开(公告)号：DE69722169D1

公开(公告)日：2003-06-26

申请号：DE69722169

申请日：1997-09-25

Applicant: MICROCHIP TECH INC

Inventor： HULL L ,  YACH L

IPC: G11C16/06 ,  G11C5/14 ,  G11C16/30 ,  G11C16/26 ,  G11C16/08

Abstract: A technique is disclosed for reading a memory element of an EPROM array embedded in a microcontroller chip which has been scaled down from a previous design by virtue of reduced line widths of a process technology used for fabricating the chip. The microcontroller chip has a predetermined supply voltage, and the array comprises rows and columns of addressable memory elements which may be selectively accessed to read data content therefrom in a low voltage mode in which the supply voltage initially rises and ultimately reaches substantially its maximum voltage during a read cycle. A regulated reference voltage is used to exercise row and column control in the low voltage read mode by tracking the level of the supply voltage up to a certain preselected level below the maximum supply voltage, and by clamping the row and column control voltage at substantially the preselected level despite increases in the level of the supply voltage above the preselected level.

公开(公告)号：DE69714824T2

公开(公告)日：2003-05-28

申请号：DE69714824

申请日：1997-05-21

Applicant: MICROCHIP TECH INC

Inventor： HULL L ,  BINGHAM GREGORY

IPC: G06F1/10 ,  G06F1/08 ,  G06F1/12 ,  G06F15/78 ,  H03K3/0231 ,  H03K17/16 ,  H03L7/00

Abstract: A microcontroller circuit having firmware selectable oscillator trimming includes, in combination, a microcontroller, an oscillator located within the microcontroller for providing a system clock signal for the microcontroller, and a memory portion for providing trimming data to the oscillator for trimming frequency of the system clock. The microcontroller circuit includes microcontroller logic which has the trimming data stored therein for transfer to the memory portion. Additionally, the microcontroller logic permits the user to alter the trimming data after it has been transferred to the memory portion, thereby permitting the user to alter the amount of modification of the system clock frequency from the amount associated with the trimming data.

公开(公告)号：DE69714824D1

公开(公告)日：2002-09-26

申请号：DE69714824

申请日：1997-05-21

Applicant: MICROCHIP TECH INC

Inventor： HULL L ,  BINGHAM GREGORY

IPC: G06F1/10 ,  G06F1/08 ,  G06F1/12 ,  G06F15/78 ,  H03K3/0231 ,  H03K17/16 ,  H03L7/00

Abstract: A microcontroller circuit having firmware selectable oscillator trimming includes, in combination, a microcontroller, an oscillator located within the microcontroller for providing a system clock signal for the microcontroller, and a memory portion for providing trimming data to the oscillator for trimming frequency of the system clock. The microcontroller circuit includes microcontroller logic which has the trimming data stored therein for transfer to the memory portion. Additionally, the microcontroller logic permits the user to alter the trimming data after it has been transferred to the memory portion, thereby permitting the user to alter the amount of modification of the system clock frequency from the amount associated with the trimming data.

公开(公告)号：DE69616266D1

公开(公告)日：2001-11-29

申请号：DE69616266

申请日：1996-07-17

Applicant: MICROCHIP TECH INC

Inventor： YACH L ,  HULL L

IPC: G11C5/14 ,  H02H3/24 ,  H02J1/00 ,  H03K17/14 ,  H03K17/22 ,  G11C16/06

Abstract: A power-on reset (10) for resetting electronic circuitry to be monitored has been provided. The power-on reset circuit includes a trip point generator (12) including the worst case component (the component that requires the greatest power supply voltage to operate) within the electronic circuitry for setting the threshold voltage for taking the electronic circuitry out of reset such that if the worst case component is operative, it is guaranteed that all components are operative and, thus, the electronic circuitry can be taken out of reset. Moreover, because the threshold voltage is based upon the worst case component of the electronic circuitry, the threshold voltage of the trip point generator will adequately track the electronic circuitry over normal process and temperature variations. Additionally, the power-on reset circuit includes a noise filter (34) for placing the electronic circuitry back into reset if variations within the power supply voltage cause the power supply voltage level to fall below a predetermined threshold for at least a minimum period of time.