Abstract: A controlled area network (CAN) driver provides improved symmetry between its differential output signals CAN-H and CAN-L, and provides protection for its low voltage devices from voltage transients occurring on its output lines. A plurality of CAN drivers 80 are serially interconnected to form a driver system, wherein each downstream driver stage receives a time-delayed form of the digital input signal TxD, each stage providing a time-delayed contribution to the differential output signals of the overall driver system.

Abstract: An EEPROM cell (10) formed on a substrate (18) using conventional process steps is provided. The cell (10) includes first (12) and second (14) conductive regions in the substrate (18) below the substrate's outer surface (28), and the first (12) and second (14) conductive regions are laterally displaced from one another by a predetermined distance (32). The cell (10) also includes an insulating layer (20) outwardly from the outer surface (28) of the substrate (18) positioned so that its edges are substantially in alignment between the first (12) and second (14) conductive regions. The cell (10) further includes a floating gate layer (22) outwardly from the insulating layer (20) and in substantially the same shape as the insulating layer (20). The cell (10) also includes a diffusion region (24 or 26) that extends laterally from at least one of the first (12) and second (14) conductive regions so as to overlap with the insulating layer (20).

Abstract: A voltage level shifting circuit (60) and method for accomplishing a voltage level change includes a voltage level shifting circuit (65) to change an input voltage to a shifted voltage level. A second stage (67) is connected between a voltage source at the shifted voltage level (68) and the reference potential. The second stage (67) includes active devices (66,82) that are controlled by the voltage level shifting circuit (65). The second stage (67) also includes slope resistors (86,88) connected in series between the active devices (66,82) of the second stage (67).

Abstract: An integrated circuit chip (10, 50, 100) may comprise an integrated circuit (14, 54, 108, 110, 112) formed in a semiconductor layer (12, 52, 102). A thermal contact (16, 56, 116) may be formed at a high temperature region of the integrated circuit (14, 54, 108, 110, 112). A thick plated metal layer (40, 80, 140) may be generally isolated from the integrated circuit (14, 54, 108, 110, 112). The thick plated metal layer (40, 80, 140) may include a base (42, 82, 142) and an exposed surface (44, 84, 144) opposite the base (42, 82, 142). The base (42, 82, 142) may be coupled to the thermal contact (16, 56, 116) to receive thermal energy of the high temperature region. The exposed surface (44, 84, 144) may dissipate thermal energy received by the thick plated metal layer (40, 80, 140).

Abstract: A internal circuitry protection scheme which protects on-IC circuitry when an external pin is shorted to a higher than normal voltage. The disclosed solution eliminates cross-talk due to a parasitic NPN.

Abstract: A circuit for protecting a transistor against electrical transients. The circuit comprises a first diode coupled between a first terminal coupled to a power supply and a control terminal of the protected transistor. The circuit also comprises a second diode and a resistor coupling the control terminal of the protected transistor to a reference potential. A second transistor is coupled in shunt to the protected transistor. The voltage on the control terminal of the second transistor is determined by the current through the resistor. The embodiments may be implemented in an integrated circuit wherein the second, shunting transistor is formed from parasitic elements within the semiconductor body in which the protected transistor is formed. In one embodiment, the protected MOS transistor is formed in an n-well 504 and a shunting bipolar transistor is formed between the n-well 504 and an n-doped guard ring 500 formed adjacent to the n-well in the p-doped substrate 508.

Abstract: A transistor including a source region 506 in a semiconductor body 502; a bulk region 508 in the semiconductor body adjacent the source region; a drain region in the semiconductor body adjacent the bulk region but opposite the source region, the drain region including doped regions 504,514 of n and p dopant types; and a field plate 516 formed over the semiconductor body adjacent the drain region between the drain region and the bulk region.

Abstract: A switch-mode power regulator includes a turn-on controller 52 to limit, during a fixed period of time, the initial current passing through the regulator following turn-on. During this time period the storage elements of the regulator must achieve an acceptable level of stability without excessive current flow. Turn-on controller 52 comprises a divider 72 which clocks zeroes along the length of a shift register 74 which is initially preset to all ones. The outputs of the shift register are coupled to a decoder 76, whose input signals are sequentially steered to its output under the control of a counter 70. The output signal from decoder 76 functions as the power regulator switching signal from turn-on controller 52. Counter 70 cycles many times for each data shift of shift register 74. Thus, turn-on controller 52 generates a train of negative pulses which increase in length monotonically for the duration of the sequence.

Abstract: An internal circuitry protection scheme which protects on-IC circuitry when an external regulator voltage pin is shorted to a higher voltage. The circuit prevents damage to the on-die circuitry that is on the internal voltage rail, by clamping the received voltage, thereby eliminating the chance of damaging the on die circuitry. The circuit offers protection even if the voltage difference is large, but the difference remains small between the internal rail and the external regulated voltage under normal operation.

Abstract: An optimized power output clamping structure, includes a power output transistor having a first breakdown voltage and a breakdown structure having a second breakdown voltage coupled to the power output transistor. The second breakdown voltage is less than the first breakdown voltage and follows the first breakdown voltage across all temperature and semiconductor process variations. This feature allows a reduction in breakdown voltage guardbanding and increases output structure reliability. A method of protecting a circuit from inductive flyback is also disclosed. The method includes the steps of driving an inductive load with drive circuitry, turning off the inductive load, and clamping an inductive voltage at a voltage magnitude that protects the drive circuitry from breakdown across all temperature and processing variations.

Abstract: The device has a semiconductor chip having active circuitry in the face thereof. The circuitry has busing over it containing two conductive layers having a plurality of contacts and vias with spacings between them that alternate with respect to one another to provide current ballasting and improved switching uniformity. The spacings between the alternating contacts and vias provide regions of maximum conductor thickness and therefore reduces the busing resistance. Staggering the rows of alternating contacts and vias provides further current ballasting. A first conducting layer is used to contact and provide electrically isolated low resistive conducting paths to the various semiconductor regions while the second conducting region is used to provide selective contact to the first conductive layer, thus providing a means of busing large currents over active semiconductor area without sacrificing performance parameters.

Abstract: A switch mode regulator circuit is provided to facilitate the conversion from one voltage level to another in a substantially power lossless manner. The circuit is particularly advantageous in instances where the power supply can be operable in a discontinuous mode, as inductor-capacitor oscillatory transients ("ringing"), along with its associated voltage spikes at the associated output transistor source, can be avoided. Such transients and their associated voltages are avoided by clamping the gate-source voltage on the circuit's output NMOS transistor over the entire positive operation voltage range.

Abstract: A testable temperature warning circuit (120) in an integrated circuit substrate (124) provides a warning if the substrate temperature exceeds a critical temperature. A programming circuit (140) controls a selection, circuit (128) to establish a programmably selectable temperature at either the critical temperature or a second predetermined temperature lower than the critical temperature to enable the warning circuit operation to be tested at a temperature lower than the critical temperature. In one embodiment, the selection circuit 128 comprises a current source that produces a voltage drop across the resistor 121 and base-emitter of the transistor 122 produces a substrate temperature indicating current of magnitude related to the temperature of the substrate. The substrate temperature indicating current at the second temperature is extrapolatingly related to the substrate temperature indicating current at the critical temperature.

Abstract: A circuit and method for providing a low drop out voltage regulator. A source follower circuit is provided having a transistor (MD1) with an output terminal for driving a load at its source terminal and a voltage supply coupled to the drain terminal. At least one diode (D1) is coupled between the gate terminal and a ground reference to provide a predetermined voltage at the gate of the transistor (MD1). A voltage multiplier circuit is provided having an input (IN) for receiving an oscillating input voltage and a charge storage device (39) coupled between the oscillating input and a voltage reference (Vref), and being further coupled in series with the voltage reference and then to the gate terminal of the transistor (MD1). The oscillating input voltage is used to charge the charge storage device (39) to a voltage approximately equal to the voltage reference.

Abstract: The device has a semiconductor chip having active circuitry in the face thereof. The circuitry has busing over it containing two conductive layers having a plurality of contacts and vias with spacings between them that alternate with respect to one another to provide current ballasting and improved switching uniformity. The spacings between the alternating contacts and vias provide regions of maximum conductor thickness and therefore reduces the busing resistance. Staggering the rows of alternating contacts and vias provides further current ballasting. A first conducting layer is used to contact and provide electrically isolated low resistive conducting paths to the various semiconductor regions while the second conducting region is used to provide selective contact to the first conductive layer, thus providing a means of busing large currents over active semiconductor area without sacrificing performance parameters.

Abstract: In accordance with the present invention, an output current limit circuit for protecting a power MOS output device of an integrated circuit from an excessive drain current comprises a power MOS device 110, sensing circuitry 30 to sense a predetermined trigger current, and limitation circuitry 20 to reduce a gate-source voltage on MOS output device 110 to a predetermined approximately fixed value. A drain current I.sub.D flows through power MOS device 110 from output terminal 102 in response to the gate-source voltage. A short circuit condition may allow an excessive amount of drain current I.sub.D to flow through output terminal 102. The gate-source voltage is reduced in response to sensing the trigger current. Reducing the gate-source voltage raises a drain-source resistance of MOS device 110 and reduces drain current I.sub.D so that MOS device 110 is not damaged by the short circuit condition.

Abstract: In accordance with the present invention, an output current limit circuit for protecting a power MOS output device of an integrated circuit from an excessive drain current comprises a power MOS device 110, a means 30 to sense a predetermined trigger current, and a means 20 to reduce a gate-source voltage on MOS output device 110 to a predetermined approximately fixed value. A drain current I.sub.D flows through power MOS device 110 from output terminal 102 in response to the gate-source voltage. A short circuit condition may allow an excessive amount of drain current I.sub.D to flow through output terminal 102. The gate-source voltage is reduced in response to sensing the trigger current. Reducing the gate-source voltage raises a drain-source resistance of MOS device 110 and reduces drain current I.sub.D so that MOS device 110 is not damaged by the short circuit condition.

Abstract: A circuit for programming an EEPROM 42 which is used to provide trim adjustment for an integrated circuit (IC). The programming circuit provides the capability of programming the EEPROM 42 indefinitely, employing interfaces which are available even after the IC is packaged and encapsulated. Furthermore, it provides the manufacturer or enduser the capability of disabling the programming function permanently, to thereby prevent any inadvertent modifications of the EEPROM 42 data. The programming circuit includes a one-bit EEPROM 32, a nonvolatile memory element which retains its programmed logic state whether or not it is powered up. EEPROM 32 is set during final probe test by the application of a voltage to a probe pad 30 coupled to its set input terminal. Probe pad 30 is exposed such that it may be contacted by a probe prior to IC encapsulation, but is inaccessible after encapsulation.

Abstract: An integrated power device comprises a power transistor (26) and a plurality of sense transistors (38), (40), (42), (44), and (46). Sense transistors (38), (40), (42), and (44) are constructed around the periphery of the active area occupied by power transistor (26). Sense transistor (46) is located within the interior of the active area occupied by power transistor (26) and contact is made to the necessary source region (64) of transistor (46) using a second level of metal interconnect to form a source contact (74).