Search Results

TIGHTLY MATCHED, MONOLITHIC DUAL, NPN TRANSISTOR < Back LS3250 Series - Dual TIGHTLY MATCHED, MONOLITHIC DUAL, NPN TRANSISTOR Previous Next

LOG CONFORMANCE, MONOLITHIC DUAL, NPN TRANSISTOR < Back LS318 LOG CONFORMANCE, MONOLITHIC DUAL, NPN TRANSISTOR Previous Next

< Back Designing Audio Circuits and Systems Linear Systems Jul 25, 2024 Exploring Phono Preamp Circuits with Bob Cordell’s New Book At Linear Systems, we are always on the lookout for innovative and educational resources to share with our community of designers and engineers. This Friday, we are thrilled to spotlight a phono preamp circuit from our friend Bob Cordell’s excellent new book, “Designing Audio Circuits and Systems.” Bob Cordell is a respected authority in the field of audio electronics, and his latest book is a treasure trove of knowledge for anyone interested in audio circuit design. The book is packed with detailed explanations, practical insights, and a wide range of circuits that cater to both beginners and seasoned designers. One of the standout chapters for us is Chapter 15, which delves into the design of moving magnet phono preamps. Phono preamps are essential for amplifying the signal from a turntable to a level that can be processed by a standard audio system. The moving magnet preamp circuit featured in Chapter 15 is not only a fantastic educational tool but also a highly practical design for anyone looking to enhance their vinyl listening experience. To bring this design to life, we captured the schematic in QSPICE, our go-to tool for electronic circuit simulation. QSPICE allows us to create accurate simulations, enabling designers to tweak and optimize their circuits with ease. With just a few clicks, you can dive into simulations and start experimenting with the design parameters to see how they affect the performance of the preamp. Whether you are an audio enthusiast, a professional designer, or someone with a keen interest in electronics, Bob Cordell’s book and this phono preamp circuit offer a wealth of knowledge and a fun project to work on. We highly recommend adding “Designing Audio Circuits and Systems” to your library and exploring the many circuits it has to offer. Stay tuned for more exciting designs and insights from Linear Systems. Happy designing!

SINGLE, ULTRA-LOW NOISE, P-CHANNEL JFET AMPLIFIER < Back LSJ/SST74 Series SINGLE, ULTRA-LOW NOISE, P-CHANNEL JFET AMPLIFIER The LSJ/SST74 Single, Ultra-Low noise, P-Channel JFET Amplifier is a direct replacement for the Toshiba 2SJ74. It is ideal for Ultra-Low Noise Audio/Acoustic Applications. Available in the TO-92 3L RoHS, SOT-89 3L RoHS, as well as in die form. Advanced screening options are available for our diverse product lineup, featuring JFETS, Bipolar transistors, MOSFETs, current regulators, and Diodes. Our special screening covers all the parameters listed in the standard datasheet, including comprehensive package pin-out. Connect with our experienced technical team to discuss your specific needs and tailor your requirements—email us at support@linearsystems.com or call (510) 490-9160. MOQ applies to these specialized services. Ordering Information: Below are the options you have when ordering this part series: LSJ74A TO-92 3L RoHS LSJ74B TO-92 3L RoHS LSJ74C TO-92 3L RoHS LSJ74D TO-92 3L RoHS SST74A SOT-23 3L RoHS SST74B SOT-23 3L RoHS SST74C SOT-23 3L RoHS SST74D SOT-23 3L RoHS Datasheet Spice Model Application Notes

< Back J201 App Note Introduction Linear Systems products enable customers to build the lowest-noise signal chains possible. The J201 N-channel JFET is optimized for high gain. The part is particularly suitable for use in low power or high impedance amplifiers. Read More

< Back Military Sensor Signal Chains Introduction Higher-performance sensors are becoming increasingly important to modern battlefield systems. Sensors ranging from sonobuoys to radiation detectors are critical, leading-edge components of C4ISR systems. Better sensor systems enable earlier threat detection and more effective countermeasures. Military systems employ a wide range of sensors – nuclear, biological, and chemical sensing, infrared, electro-optical, laser, radar, and acoustical – that all have one aspect in common: the requirement for ultra-low-noise signal chains to produce the best possible sensor signal. Less-than-optimal front-end amplification means C4ISR clients receive inadequate information and are not able to make effective, real-time decisions. This paper describes techniques to employ to create the lowest-noise, most effect front-end amplification for sensor signal chains. Advanced lithography design and fab process techniques enable the creation of discrete components uniquely capable of performing the critical initial amplification of sensor signals. Integrated circuits contain a wide range of components and can include specialized design features that preclude design optimization for low noise. As this paper documents, ultra-low-noise discrete components added to an IC-based circuit will produce the lowest-noise signal chain. Though this paper focuses on the LSK489 dual monolithic Nchannel JFET, many other Linear Systems parts -- including the LSK389, LSK170 and LSK189 -- also are excellent sensor system components. Linear Systems is the world leader in ultra-low-noise monolithic dual JFETs and other front-end discrete components key to high-performance sensing systems. For over three decades, Linear Systems has led the development of this class of devices, and it continues to advance their design and introduce new sensor-specific parts. Read More

< Back LS26VPS/VNS Press Release Linear Systems Mar 17, 2023 New JFET Voltage-Controlled Resistors NEWS RELEASE FOR INFORMATION CONTACT: Linear Systems, Inc. Sales Department Phone: (510) 490-9160 Email: sales@linearsystems.com Build lower-voltage, lower-power circuits using Linear Systems' industry-leading voltage-controlled resistors. Linear Systems has expanded its family of JFET Voltage-Controlled Resistors (VCRs) for reduced-power circuits over IC-based devices. Two new additions to the JFET Voltage-Controlled Resistor Family include the LS26VNS, a Single N-Channel JFET VCR, and the LS26VPS, a Single P-Channel JFET VCR. Both the N and P-channel versions are made from the same die geometry, making them complementary. They join the existing VCR11N, a Dual N-Channel VCR. The advantages of using VCRs for voltage-controlled amplifier or voltage-controlled gain systems include: - VCR-based devices operate with lower voltage and power consumption, enabling battery-powered systems to last significantly longer. - VCR JFETs can be used with low-power op amps to provide a low-power solution for voltage-controlled gain systems. - With low voltage op amps such as the LMV358 or TLC272, VCR JFETs perform voltage-controlled gain at extremely low supply voltages, down to a single 3.3V power supply. Circuits can be designed for very low power consumption when combined with low voltage, low power op amps. For instance, using an LSK389A as a VCR for these low voltage circuits can provide significant efficiency gains. - Matched pair JFET VCRs (VCR11N or LSK389A) can provide two identical channels of voltage-controlled gain, where the control voltage tracks both channels. This can be used in stereo audio signal attenuation. In contrast, typical active voltage-controlled amplifiers drain more current and require higher minimum power supply voltages, needing at least +/- 4 volts for a specialized voltage control amplifier integrated circuit. P-Channel JFETs, including a J177, can be designed as a VCR circuit with a single power supply. For example, the P-Channel JFET VCR circuit is ideal with positive supply voltages since its control voltage to the gate is also positive. Product Details: - LS26VNS N-Channel Single JFET VCR: Drain-source resistance is controlled by a DC bias voltage (VGS) applied to a high impedance gate terminal. Minimum RDS of 14 Ω occurs when VGS = -1.0V. As VGS approaches the pinch-off voltage of -6.0V, RDS rapidly increases to the maximum value of 38 Ω. - LS26VPS P-Channel Single JFET VCR: Drain-source resistance is controlled by a DC bias voltage (VGS) applied to a high impedance gate terminal. Minimum RDS of 20 Ω occurs when VGS = 3.0V. As VGS approaches the pinch-off voltage of 7.5V, RDS rapidly increases to the maximum value of 50 Ω. Summary of Features : - LS26VNS (N-Channel Single) - RDS(on) 14-38 Ω - BVgss 30 Volts - Available in TO-92 3L, SOT-23 3L, DFN 8L, and Bare Die options - LS26VPS (P-Channel Single) - RDS(on) 20-50 Ω - BVgss 30 Volts - Available in TO-92 3L, SOT-23 3L, DFN 8L, and Bare Die options Applications: - Variable Gain Controls - Voltage Controlled Oscillators - Signal Attenuators - Musical Effects Applications - Adaptive Analog Filters - Automatic Gain Control Circuits - Clock Generators - Compressors - Electrometers - Energy Harvesters - Expanders - Hearing Aids - Light Dimmers - Modulators - Mixers - Artificial Neural Networks - Programmable Gain Amplifiers - Phased Arrays - Phase Lock Loops - Phase Controlled Dimming Circuits - Phase Delay and Advance Circuits - Tunable Filters - Variable Attenuators - Voltage Controlled Multivibrators - Waveform Generators Pricing and Availability: - 1,000+ pieces of the LS26VNS and LS26VPS in the TO-92 3L, SOT-23 3L, and DFN 8L packages are priced at $1.23 (USD) each. - Production quantities are available now with delivery from factory stock to 8 weeks. This product line is supported by application notes, datasheets, and SPICE models. For further technical resources, please click HERE . About Linear Systems: Founded in 1987, Linear Systems is a full-service, privately-held designer and manufacturer of small-signal discrete semiconductors. The Fremont, CA-based company was founded by John H. Hall, co-founder of Intersil and founder of Micro Power Systems. Linear Systems' product line includes Ultra-Low-Noise N-Channel and P-Channel Dual and Single JFETs, High-Speed Lateral DMOS Switches, Bipolar Transistors, BIFET Amplifiers, Current-Regulating Diodes, Low-Leakage Diodes, MOSFETs, PhotoFETs, and Voltage-Controlled Resistors. Datasheets, application notes, SPICE models, and additional information can be found at www.linearsystems.com. For more information, contact Linear Systems at (510) 490-9160 or email sales@linearsystems.com. https://www.linearsystems.com/voltagecontrolledresistors/ls26vps

SD211DE SINGLE, HIGH-SPEED N-CHANNEL LATERAL DMOS FET SWITCH < Back SD/SST211 Series SD211DE SINGLE, HIGH-SPEED N-CHANNEL LATERAL DMOS FET SWITCH The SD/SST211 Series is a Single, High-Speed N-Channel Lateral DMOS FET Switch with Zener Diode Protection, ideal for Ultra-High Speed Switching Applications. Linear Systems acquired the Siliconix Lateral DMOS FET Switch product line, so our version is the same maskset, same process and is an exact pin-for-pin replacement. The series is available in the TO-72 4L RoHS and SOT-143 4L RoHS package, as well as bare die. Advanced screening options are available for our diverse product lineup, featuring JFETS, Bipolar transistors, MOSFETs, current regulators, and Diodes. Our special screening covers all the parameters listed in the standard datasheet, including comprehensive package pin-out. Connect with our experienced technical team to discuss your specific needs and tailor your requirements—email us at support@linearsystems.com or call (510) 490-9160. MOQ applies to these specialized services. Ordering Information Below are the options you have when ordering this part series: SD211DE TO-72 4L RoHS SD213DE TO-72 4L RoHS SD215DE TO-72 4L RoHS SST211 SOT-143 4L RoHS SST213 SOT-143 4L RoHS SST215 SOT-143 4L RoHS Datasheet Spice Model Applicaton Notes

MONOLITHIC DUAL, NPN TRANSISTOR < Back IT120 Series MONOLITHIC DUAL, NPN TRANSISTOR The IT120 Series Monolithic Dual, NPN Transistor is a direct replacement for the Intersil IT120 Series. It is ideal for Small Signal Transistor Amplifier & Switching Applications. It is available the in TO-71 6L RoHS, TO-78 6L RoHS, PDIP 8L ROHS and SOIC 8L RoHS package, as well as bare die. Advanced screening options are available for our diverse product lineup, featuring JFETS, Bipolar transistors, MOSFETs, current regulators, and Diodes. Our special screening covers all the parameters listed in the standard datasheet, including comprehensive package pin-out. Connect with our experienced technical team to discuss your specific needs and tailor your requirements—email us at support@linearsystems.com or call (510) 490-9160. MOQ applies to these specialized services. Ordering Information: All Part Numbers within this Product Series IT120A PDIP 8L RoHS IT120 PDIP 8L RoHS IT121 PDIP 8L RoHS IT122 PDIP 8L RoHS IT120A SOIC 8L RoHS IT120 SOIC 8L RoHS IT121 SOIC 8L RoHS IT122 SOIC 8L RoHS IT120A Die IT120 Die IT121 Die IT122 Die Datasheet Spice Model Application Notes

< Back Interfacing Sensors & Transducers Introduction Abstract: A discussion of methods of amplifying and signal-conditioning for sensors with low level outputs in the presence of high ambient electrical noise sources. Advantages and disadvantages of some common amplifier circuits are considered. Read More

LOW NOISE N-CHANNEL JFET GENERAL PURPOSE AMPLIFIER < Back J/SST210 Series LOW NOISE N-CHANNEL JFET GENERAL PURPOSE AMPLIFIER The J/SST210 Series Single, Low Noise, N-Channel JFET, General Purpose Amplifier is a direct replacement for Fairchild, NXP and Siliconix-Vishay equivalent part. It is ideal for General Purpose and Low Noise Applications. Available in the TO-92 3L RoHS, SOT-23 3L RoHS package, as well as die form. Advanced screening options are available for our diverse product lineup, featuring JFETS, Bipolar transistors, MOSFETs, current regulators, and Diodes. Our special screening covers all the parameters listed in the standard datasheet, including comprehensive package pin-out. Connect with our experienced technical team to discuss your specific needs and tailor your requirements—email us at support@linearsystems.com or call (510) 490-9160. MOQ applies to these specialized services. Ordering Information Below are the options you have when ordering this part series: J210 TO-92 3L RoHS J211 TO-92 3L RoHS J212 TO-92 3L RoHS SST210 SOT-23 3L RoHS SST211 SOT-23 3L RoHS SST212 SOT-23 3L RoHS J210 Die J211 Die J212 Die Datasheet Spice Model Application Notes

< Back LS844 App Note Introduction Introduction For circuits designed to work with high impedance sources, ranging from electrometers to microphone preamplifiers, the use of a low-noise, high-impedance device between the input and the op amp is needed in order to optimize performance. At first glance, one of Linear Systems’ most popular parts, the LSK389 ultra-low-noise dual JFET would appear to be a good choice for such an application. The part’s high input impedance (1 T) and low noise (1 nV/√Hz at 1kHz and 2mA drain current) enables power transfer while adding almost no noise to the signal. But further examination of the LSK389’s specification shows an input capacitance of over 20pF. This will cause intermodulation distortion as the circuit’s input signal increases in frequency if the source impedance is high. This is because the JFET junction capacitances are nonlinear. This will be especially the case where common source amplifier arrangements allow the Miller effect to multiply the effective value of the gatedrain capacitance. Further, the LSK389’s input impedance will fall to a lower value as the frequency increases relative to a part with lower input capacitance. A better design choice is Linear Systems’ LS844. Though the LS844 has slightly higher noise (2.5 nV/√Hz vs. 1.0 nV/√Hz) its much lower input capacitance of only 4pF means that it will maintain its high input impedance as the frequency of the input signal rises. More importantly, using the lower-capacitance LS844 will create a circuit that is much less susceptible to intermodulation distortion than one using the LSK389. The LS844’s lower gate-to-drain capacitance enables more effective, elegant audio circuit designs. The relatively high capacitance of the LSK389 often requires designers to use a cascode circuit to provide the ability to handle higher bandwidths without intermodulation distortion. The cascode does this by eliminating the Miller effect that can multiply the effective gate-drain capacitance and its associated nonlinear effects. However, the cascode adds complexity and noise contributed by the cascode transistors. The LS844 is an N-channel dual low-noise, lowcapacitance, tightly matched monolithic field effect transistor. It features: • 3ms transconductance at 2mA drain current • 1000 G input impedance • 60V breakdown voltage • gate-drain capacitance of only 1.5pF • 4pF input capacitance • 2.5 nV/√Hz noise at 1kHz • best low-noise/low-capacitance combination in the industry • lowest input capacitance per unit gate length in the industry • lowest noise for a given gate length in the industry • tight Vgs matching at operating bias The LS844 is particularly well suited to low-noise, highgain audio and instrumentation circuits operating from battery voltages up to 60 volts. 48V phantom-powered circuits, like those used in microphone preamplifiers, are especially benefited by the features of the LS844. Low operating Vgs, high gm, tight matching, low noise and low capacitance make it well-suited to numerous audio and instrumentation applications. Sensors, which play such an important role in today’s world, benefit greatly from the performance delivered by the LS844. Such sensor technologies include piezo, quartz, condenser, electret, and MEMs devices. These devices benefit from the LS844’s combination of low input capacitance and low noise. Electrometer applications also benefit from these characteristics. Read More