The IEEE Standard 1149.1-1990, IEEE Standard Test Access Port and Boundary-Scan Architecture (JTAG) is a method for verifying designs and testing printed circuit boards after assembly. It is used as the primary means for transferring data to a nonvolatile memory of an embedded system and debugging embedded software.
This application report describes the physical connections for JTAG and design considerations to be taken into account for a custom board. It also shows how to use the JTAG interface on the SimpleLink™ MSP432E4 LaunchPad™ development kit for debugging the onboard microcontroller using an external debugger, or by using the onboard debugger for debugging an off-board microcontroller.
In the past several years, multiple digital and wireless ultrasound probes have been introduced to physicians as vision-enhanced stethoscopes, which may someday replace the traditional 150-year-old stethoscope. GE’s Vscan, Siemens’ Freestyle, SonoSite's iViz and Philips’ Lumilify are among the first wave of ultra-portable probes for physicians and rural villages. Ultrasound imaging may be the only modern imaging modality choice for rural areas because of its cost-effectiveness and portability. It is exciting to TIers to innovate and deliver solutions to serve people who may have never been served by modern medicine.
Further reducing power requirements and increasing image quality demands high channel count and low power ICs. The AFE5832LP and AFE5832 devices are designed to address these needs. The AFE5832 is industry’s first 32-CH analog front-end (AFE) solution, and the AFE5832LP is its lower power version. Both devices are pin-to-pin compatible. The AFE5832LP achieves power consumption of < 20 mW/CH, which is approximately 6× lower than the power consumption of the AFE5818 and AFE5808 devices in traditional console systems.
Functions of comfort and convenience available in all modern vehicles today (and in the foreseeable future) rely on body control modules (BCMs). BCMs work behind the scenes to operate headlights, rear lights, interior ambient lights, windshield wipers and more.
Both the quantity of BCMs in a car and the number of comfort and convenience loads that each BCM controls vary across vehicle models. From a BCM that only handles lighting functions to a BCM that includes gateway functionality and car-access support, the number of BCMs and their complexity depend on the underlying architecture of the vehicle body electronics.
BCM designs are also rapidly evolving. For example, junction boxes (also known as power distribution boxes), which distribute power to various loads using relays, are either being integrated into BCMs or converted to BCM-like modules to distribute power through semiconductor switches. More driver inputs and sensors are being connected to BCMs as the number of comfort and convenience features increases. And as the number of dedicated load-control modules (such as those for roof motor control) increases, BCM networking requirements also increase.
CAN interface has been a very popular serial communication standard in the industry due to its excellent prioritization and arbitration capabilities. In systems with different voltage domains, isolation is typically used to protect the low voltage side from the high voltage side in case of any faults. Isolation also breaks any ground loops allowing only the desired signals to be transmitted, thereby improving signal quality.
Isolated CAN is used for communication with the microcontroller in a wide range of applications such as solar inverters, circuit breakers, motor drives, PLC communication modules, telecom rectifiers, elevators, HVACs and EV charging infrastructures.
Time-sensitive networking (TSN) is an Ethernet extension defined by the Institute of Electrical and Electronic Engineers (IEEE) designed to make Ethernet-based networks more deterministic. Industries like automotive, industrial and performance audio use real-time communication with multiple network devices and will benefit from the TSN standard.
The consumer and enterprise world of Ethernet and wireless Ethernet communication is bandwidth oriented. For example, while browsing the Internet you accept a varying amount of delay before video playback starts. Although there is a preference for quick interaction, for the average user it is acceptable if one out of 100 clicks perform an order of magnitude worse. However, if a video is bad quality or even halted the typical consumer will be frustrated.
Even infrequent delays are unacceptable in control systems such as those inside automobiles, production lines or concert halls. The most important aspects for these systems are latency and jitter or variation in the latency of control data through the network. The maximum time a packet takes to reach the destination in the system defines the communication cycle or control frequency in the network.
All DC/DC converters dissipate power in the form of heat. This heat has to be managed properly so that the converter maintains operation within the recommended temperature limits. Usually, the copper on the printed circuit board (PCB) is utilized to help dissipate the heat. This application note outlines a design procedure to quickly estimate the minimum required copper area on the PCB for a successful thermal design with DC/DC power modules.
The gate driver in a motor system design is an integrated circuit (IC) that primarily deals with enhancing external power MOSFETs to drive current to a electric motor. The gate driver acts as an intermediate stage between the logic-level control inputs and the power MOSFETs. The gate driver must be robust and flexible enough to accommodate a wide variety of external MOSFET selections and external system conditions.
Texas Instrument’s Smart Gate Drive provides an intelligent solution for driving and protecting the external power MOSFETs. This feature lets system designers adjust the MOSFET slew rate, optimize switching and EMI performance, decrease bill of materials (BOM) count, automatically generate dead-time, and provide additional protection for the external power MOSFETs and motor system.
This application report describes the theory and methods behind enhancing a power MOSFET, how the IDRIVE and TDRIVE features are implemented in TI Smart Gate Drivers, and details many of the systemlevel benefits.
As gallium nitride (GaN) power FETs become readily available for power designers to use, their promise of performance improvement with higher efficiencies and greater power densities can begin to become realized. By having better material properties over silicon, loss elements such as on-state resistance Rds(on) and output capacitance Coss are smaller for an equal die area. These GaN power FET devices, included in the LMG3410x family, are typically offered in high electron mobility transistor (HEMT) structures, which along with maximizing the material property benefits eliminate the reverse recovery Qrr when the device operates in third quadrant mode (conduction from source to drain). These benefits allow GaN power FETs to operate faster and at higher frequencies than previously capable. With typical slew rates around 30 V/ns to 100 V/ns at operating voltages around 380 V to 480 V, printed circuit board (PCB) layout optimization is even more essential since parasitic inductances and capacitances from poor layouts can drastically reduce performance or even prevent operation. When pushed to their limits to maximize system gains power GaN FETs provide the device can degrade and potentially overheat without a carefully designed thermal system to dissipate the generated heat. To prevent these problems from hampering designs and limiting performance layout recommendations, peripheral component selection and thermal system design are discussed.
This cookbook design describes a temperature measurement circuit with two thermocouples using the ADS1118. Thermocouple voltage measurements are made with the ADS1118 internal voltage reference, while cold-junction compensation (CJC) measurements are made with the onboard temperature sensor. Two channels of the ADC are used for two K-type thermocouples with a temperature measurement range from –270°C to 1370°C. Included in this design are ADC register settings to configure the device and pseudo code is provided to configure and read from the device. This circuit can be used in applications such as analog input modules for PLCs, lab instrumentation, and factory automation.
The LMZM33606 is a 16 × 10 mm2 6-A rated synchronous step-down power module that features a wide operating input range from 3.5 V to 36 V with adjustable output voltage range from 1 V to 20 V. The LMZM33606 can be configured in an inverting buck-boost (IBB) topology with the output voltage inverted or negative with respect to input voltage. This application report shows how the conventional non-inverting evaluation board for the LMZM33606 can be configured for an inverting application. This application note also provides the additional level-shifter circuitry for EN and PGOOD pin if the feature is required. Note that the LMZM33604 is rated for 4A and pin-to-pin compatible with the LMZM33606.