scholarly journals Minimum dropout voltage on a serial pnp transistor of a moderately loaded voltage regulator in a gamma radiation field

2012 ◽  
Vol 27 (4) ◽  
pp. 333-340 ◽  
Author(s):  
Vladimir Vukic
Keyword(s):  
Integrated Circuit ◽  
High Current Density ◽  
Negative Influence ◽  
Radiation Hardness ◽  
Voltage Regulators ◽  
Current Gain ◽  
Voltage Regulator ◽  
Emitter Current ◽  
Moderate Load ◽  
Loaded Voltage

The main examined value in an experiment performed on moderately loaded voltage regulators was the serial pnp transistor?s minimum dropout voltage, followed by the data on the base current and forward emitter current gain. Minimum dropout voltage decreased by up to 12%, while the measured values of the forward emitter current gain decreased by 20-40% after the absorption of a total ionizing dose of 500 Gy. The oxide trapped charge increased the radiation tolerance of the serial lateral pnp transistor owing to the suppression of interface trap formation above the base area. Current flow through the serial transistor of the voltage regulator had an influence on the decrease in the power pnp transistor?s forward emitter current gain. Due to the operation with a moderate load of 100 mA, loss of emitter injection efficiency was not as important as during the operation with high current density, thus eliminating the negative influence of emitter crowding on the radiation hardness of the voltage regulator. For a moderate load, gain in the negative feedback reaction was enough to keep output voltage in the anticipated range. Only information procured from tests of the minimum dropout voltage on the moderately loaded voltage regulators were not sufficient for unequivocal determination of the examined integrated circuit?s radiation hardness.

scholarly journals Power lateral pnp transistor operating with high current density in irradiated voltage regulator

2013 ◽  
Vol 28 (2) ◽  
pp. 146-157 ◽  
Author(s):  
Vladimir Vukic ◽  
Predrag Osmokrovic
Keyword(s):  
Current Density ◽  
High Current Density ◽  
Positive Influence ◽  
Radiation Hardness ◽  
Current Gain ◽  
Voltage Regulator ◽  
Interface Traps ◽  
High Current ◽  
Oxide Trapped Charge ◽  
Trapped Charge

The operation of power lateral pnp transistors in gamma radiation field was examined by detection of the minimum dropout voltage on heavily loaded low-dropout voltage regulators LM2940CT5, clearly demonstrating their low radiation hardness, with unacceptably low values of output voltage and collector-emitter voltage volatility. In conjunction with previous results on base current and forward emitter current gain of serial transistors, it was possible to determine the positive influence of high load current on a slight improvement of voltage regulator LM2940CT5 radiation hardness. The high-current flow through the wide emitter aluminum contact of the serial transistor above the isolation oxide caused intensive annealing of the positive oxide-trapped charge, leading to decrease of the lateral pnp transistor's current gain, but also a more intensive recovery of the small-signal npn transistors in the control circuit. The high current density in the base area of the lateral pnp transistor immediately below the isolation oxide decreased the concentration of negative interface traps. Consequently, the positive influence of the reduced concentration of the oxide-trapped charge on the negative feedback reaction circuit, together with the favourable effect of reduced interface traps concentration, exceeded negative influence of the annealed oxide-trapped charge on the serial pnp transistor's forward emitter current gain.

scholarly journals Impact of forward emitter current gain and geometry of pnp power transistors on radiation tolerance of voltage regulators

2010 ◽  
Vol 25 (3) ◽  
pp. 179-185 ◽  
Author(s):  
Vladimir Vukic ◽  
Predrag Osmokrovic
Keyword(s):  
Area Ratio ◽  
Voltage Regulators ◽  
Current Gain ◽  
Maximum Output ◽  
Output Current ◽  
Emitter Current ◽  
Power Transistors ◽  
Operational Characteristics ◽  
Rapid Fall ◽  
A Minor

Low-dropout voltage regulators with various geometries and technological realisations of serial pnp power transistors were exposed to ionizing radiation. Although devices with vertical emitters were considered much less susceptible to the influence of radiation on forward emitter current gain than circuits with round emitters, the experiment showed a similar degradation of current gain in both cases. The main reason of high radiation susceptibility of the examined vertical serial pnp transistor is the implementation of an interdigitated emitter, with high perimeter-to-area ratio, causing the great increase of serial transistor?s base current, but a minor influence on the maximum output current. Transistors with round emitters with small perimeter-to-area ratio expressed a moderate current gain degradation, but a rapid fall of the emitter injection efficiency, causing a significant decrease of the maximum output current. Regardless of the similar forward emitter current gain degradation, reliability and operational characteristics of two types of low-dropout voltage regulators were completely different.

scholarly journals On-line monitoring of base current and forward emitter current gain of the voltage regulator's serial pnp transistor in a radiation environment

2012 ◽  
Vol 27 (2) ◽  
pp. 152-164 ◽  
Author(s):  
Vladimir Vukic ◽  
Predrag Osmokrovic
Keyword(s):  
Automatic Measurement ◽  
Radiation Environment ◽  
Current Gain ◽  
Maximum Output ◽  
Emitter Current ◽  
Base Current ◽  
On Line ◽  
Considerable Degradation ◽  
Loaded Voltage ◽  
Internal Consumption

A method of on-line monitoring of the low-dropout voltage regulator's operation in a radiation environment is developed in this paper. The method had to enable detection of the circuit's degradation during exploitation, without terminating its operation in an ionizing radiation field. Moreover, it had to enable automatic measurement and data collection, as well as the detection of any considerable degradation, well before the monitored voltage regulator's malfunction. The principal parameters of the voltage regulator's operation that were monitored were the serial pnp transistor's base current and the forward emitter current gain. These parameters were procured indirectly, from the data on the voltage regulator's load and quiescent currents. Since the internal consumption current in moderately and heavily loaded devices was used, the quiescent current of a negligibly loaded voltage regulator of the same type served as a reference. Results acquired by on-line monitoring demonstrated marked agreement with the results acquired from examinations of the voltage regulator's maximum output current and minimum dropout voltage in a radiation environment. The results were particularly consistent in tests with heavily loaded devices. Results obtained for moderately loaded voltage regulators and the risks accompanying the application of the presented method, were also analyzed.

scholarly journals New Double Current Controlled CFA (DCC–CFA) Based Voltage–Mode Oscillator with Independent Electronic Control of Oscillation Condition and Frequency

2013 ◽  
Vol 64 (2) ◽  
pp. 65-75 ◽  
Author(s):  
Roman Šotner ◽  
Norbert Herencsár ◽  
Jan Jeřábek ◽  
Radek Dvořák ◽  
Aslihan Kartci ◽  
...  
Keyword(s):  
Integrated Circuit ◽  
Active Element ◽  
Frequency Tuning ◽  
Current Gain ◽  
Intrinsic Resistance ◽  
Current Feedback ◽  
Voltage Mode ◽  
Simultaneous Control ◽  
Bicmos Technology ◽  
Electronically Tunable

In this paper, a new electronically tunable quadrature oscillator (ETQO) based on two modified versions of current feedback amplifiers (CFAs), the so called double current controlled CFA (DCC-CFAs) is presented. The frequency of oscillation (FO) of the proposed voltage-mode (VM) ETQO is electronically adjustable by current gain or by varying the intrinsic resistance of the X terminal of the active element used. The condition of oscillation (CO) is adjustable by current gain independently with respect to frequency of oscillation. Simultaneous control of current gain and intrinsic resistance allows linear control of FO and provides extension of frequency tuning range. In the proposed circuit all the capacitors are grounded. The use of only grounded capacitors makes the proposed circuit ideal for integrated circuit implementation. The presented active element realized by using BiCMOS technology and the behavior of proposed circuit are discussed in details. The theoretical results are verified by SPICE simulations based on CMOS ON-Semi C5 0.5 μm and bipolar ultra high frequency transistor arrays Intersil HFA 3096 process parameters.

Package Voltage Regulators: The Answer for Power Management Challenges

2019 ◽  
Vol 2019 (1) ◽  
pp. 000438-000443 ◽  
Author(s):  
Joseph Meyer ◽  
Reza Moghimi ◽  
Noah Sturcken
Keyword(s):  
Integrated Circuit ◽  
High Performance ◽  
Power Conversion ◽  
Cmos Technology ◽  
Voltage Regulation ◽  
Voltage Regulators ◽  
Electronic Systems ◽  
Single Chip ◽  
Fully Integrated ◽  
Computational Performance

Abstract The generational scaling of CMOS device geometries, as predicted by Moore's law, has significantly outpaced advances in CMOS package and power electronics technology. The conduction of power to a high-performance integrated circuit (IC) die typically requires close to 50% of package and IC I/O and is increasing with trends towards lower supply voltages and higher power density that occur in advanced CMOS nodes. The disparity in scaling of logic, package, and I/O technology has created a significant bottleneck that has become a dominant constraint on computational performance. By performing power conversion and voltage regulation in-package, this limitation can be mitigated. Integration of thin-film ferromagnetic inductors with CMOS technology enables single-chip power converters to be co-packaged with processors, high bandwidth memory (HBM), and/or other modules. This paper highlights the advantages of fully integrated package voltage regulators (PVRs), which include: reducing package I/O allocated for power, eliminating the need for upstream power-conversion stages, and improving transient response. These benefits substantially reduce the size, weight, and power of modern electronic systems.

Hot Electron Transistors Using Si/CoSi2

1987 ◽  
Vol 102 ◽  
Author(s):  
A. F. J. Levi ◽  
R. T. Tung ◽  
J. L. Batstone ◽  
M. Anzlowar
Keyword(s):  
Current Gain ◽  
Material System ◽  
Hot Electron ◽  
Metal Base ◽  
Emitter Current ◽  
Recent Advances ◽  
Electron Transistors

ABSTRACTWe have explored the possibility of fabricating a metal base transistor in the Si/CoSi2 material system. Utilizing recent advances in the growth of thin, pinhole free, CoSi2 layers on Si(111) we have measured the transistor characteristics of a Si/CoSi2/Si structure. The observed low common emitter current gain is attributed to an absence of current carrying states in the CoSi2 transistor base.

4H-SiC Bipolar Junction Transistors with a Current Gain of 108

2008 ◽  
Vol 600-603 ◽  
pp. 1159-1162 ◽  
Author(s):  
Q. Jon Zhang ◽  
Charlotte Jonas ◽  
Albert A. Burk ◽  
Craig Capell ◽  
Jonathan Young ◽  
...  
Keyword(s):  
High Temperatures ◽  
Breakdown Voltage ◽  
Current Gain ◽  
Bipolar Junction Transistors ◽  
High Current ◽  
Emitter Current ◽  
Wide Range ◽  
Operating Temperatures ◽  
A Current

4H-SiC BJTs with a common emitter current gain (b) of 108 at 25°C have been demonstrated. The high current gain was accomplished by using a base as thin as 0.25 μm. The current gain decreases at high temperatures but is still greater than 40 at 300°C. The device demonstrates an open emitter breakdown voltage (BVCBO) of 1150 V, and an open base breakdown voltage (BVCEO) of 250 V. A low specific on-resistance of 3.6 mW-cm2 at 25°C was achieved. The BJTs have shown blocking capabilities over a wide range of operating temperatures up to 300°C.

Sign in / Sign up

Export Citation Format

Share Document