Electric vehicles and connected, automotive technologies are projected to spike in adoption, with electric vehicles (EVs) estimated to surpass internal combustion engine (ICE) vehicles by 2036 and connected technologies anticipated to generate $1,600 per vehicle by 2035.
To keep pace with this demand, semiconductor manufacturers, including Rohm, Toshiba, and Nexperia, have released new chips that target various automotive applications.
Rohm Releases New N-Channel MOSFETs
Rohm Semiconductor recently released a new series of N-channel MOSFETs with different voltage ratings of 40 V, 60 V, and 100 V, targeting automotive motors for doors, seat positioning, and power windows. The new devices also support car infotainment, displays, LED lighting, and advanced driver assistance systems (ADAS). Rohm released ten new models in three new package types: DFN2020Y7LSAA (2 mm × 2 mm) and HSMT8AG (3.3 mm × 3.3 mm) for space-constrained ADAS applications and TO-252 (6.6 mm × 10.0 mm) for larger power applications.
The compact N-channel MOSFETs employ a split-gate structure, where the gate is split into multiple parts to regulate electron flow and achieve low on-resistance. This low on-resistance significantly reduces power loss and heat generation across the device.
Inner circuit of the RF9G120BKFRA, an N-channel 40-V, 120A MOSFET. Image used courtesy of Rohm Semiconductor
Rohm plans to mass produce two new packages—DFN3333 (3.3 mm × 3.3 mm) and HPLF5060 (5 mm × 6 mm)—in October 2024, with 80-V products to follow in 2025.
Toshiba Unveils Gate Driver IC
Toshiba recently announced a new gate driver IC, the TB9103FTG (datasheet linked), for automotive brushed DC motors, including latch and lock motors that power backdoors and sliding doors and drive motors for power seats and power windows. The IC can be used alongside an N-channel MOSFET to replace mechanical relays and mechanical switches. The device can be used as a one-channel, H-bridge driver or a two-channel, half-bridge gate driver.
Functional block diagram of the TB9103FTG. Image used courtesy of Toshiba
Toshiba claims that its TB9103FTG can streamline gate driver functions and increase performance for brush DC motors that don’t require speed control. The device includes a built-in charge pump circuit to ensure that external MOSFETs that drive the motors receive their required voltage. The IC also has a gate monitoring function to prevent through-currents.
TB9103FTG is housed in a 4 mm × 4 mm package. It features low-power standby operation, a sleep function, and multiple fault detection functions, including VB/VCC low-voltage detection, VCP high-voltage detection, gate-source voltage detection, gate voltage fault shutdown, drain-source voltage detection, and overcurrent/overheat shutdown.
Nexperia Develops Transformer Drivers for EVs
Nexperia has also released new transformer push-pull drivers—the NXF6501-Q100, NXF6505A-Q100, and NXF6505B-Q100 (datasheets linked)—for small, low-EMI, and low-noise power supplies. These power supplies can be used in various components and systems within EVs and HEVs, including battery management systems (BMS), DC-DC converters, traction inverters, motor control, and on-board chargers. They can also be used in industrial applications like telecommunications, industrial automation equipment, solar inverters, energy meters, programmable logic controllers (PLC), and medical applications.
Functional block diagram of the NXF6501. Image used courtesy of Nexperia
The push-pull drivers offer 6 W of power delivery with an efficiency of 90%, according to Nexperia. The transformer drivers use an oscillator and gate drive circuit to produce output signals that drive N-channel power switches. Clock signals can also be applied to the NXF6505A and NXF6505B to control switching harmonics and synchronize multiple devices.
Nexperia claims the NXF650x(A/B)-Q100 series can efficiently drive compact, center-tapped transformers from a 2.25 V to 5.5 V power supply with a high output current of 1.2 A at 5 V. For size-constrained applications, the devices include an internal oscillator and a gate drive circuit to drive internal ground-referenced, N-channel power switches with complementary output signals. The NXF6501 and NXF6505B include a 440-kHz internal oscillator, while the NXF6505A integrates a 160 kHz oscillator. Designers can alternatively apply a clock signal externally to the NXF6505A and NXF6505B to precisely control switching harmonics or synchronize multiple NFX6505x(A/B) -Q100 devices.
The new series leverages slew rate control and spread-spectrum clocking (SSC) to minimize noise and electromagnetic interference (EMI). The transformer drivers also have a range of protection features for safety-critical EVs, including over-current protection, thermal shutdown, under-voltage protection, and lockout break-before-make circuitry. The transformer drivers also use a soft-start feature that prevents a high influx of current when being powered up with large load capacitors. Fail-safe inputs prevent back-powering of the local power supply.
What circuit-level innovations do you see changing the automotive landscape most? Share your thoughts in the comments below.
