Audio for Entertainment Consoles

Premium sound systems are proliferating throughout automotive model lineups. These sound systems need to deliver high-quality, undistorted sound, with advanced acoustic performance.

ON Semiconductor supplies key components for high-quality audio paths, specifically compandors and low-noise amplifiers.

The SA575 compandor provides the essential compression function that ensures that all parts of the audio signal are above the inherent noise floor of the transmission medium. The device provides low noise performance of 6 µV typical and 0.05% Total Harmonic Distortion, over a wide dynamic range of >110 decibels. ON Semiconductor offers a family of compandors that allow designers to optimize supply voltage, noise parameters, and other performance parameters.

The MC33078 dual channel low noise operational amplifier provides the band-pass filtering function between the CODEC and the compandor, and the low-pass filtering function between the compandor and the transmitter. This device provides high slew rate of 7 V per µs, with low noise of 4.5 nV per root Hertz and 0.002% Total Harmonic Distortion. ON Semiconductor's family of low noise operational amplifiers include single, dual, and quad channel devices; and multiple slew rate, noise, and gain-bandwidth parameters to allow for design optimization.

High-quality, low noise audio signals are essential for premium sound systems, and ON Semiconductor's compandors and low noise operational amplifiers provide key building blocks for these audio subsystems.

Audio for Headsets

Today's automotive premium sound systems often include individual headsets. These audio subsystems need to deliver high-quality, undistorted sound, without consuming much power.

ON Semiconductor's devices supply the expandor and amplification functions for high-quality audio paths.

The SA575 compandor expands the compressed audio signal that is received by a typical wireless headset subsystem. The device provides low noise performance of 6 µV typical, while consuming only 4.2 mA maximum of supply current.

The NCP2890 amplifies the expanded audio signal, delivering 1 W of continuous average power to an 8 ohm load, while consuming only 1.9 mA maximum of supply current. The device also includes circuitry that prevents ‘pop and click' noise during turn-on and turn-off transitions.

ON Semiconductor's full portfolio of high performance audio amplifiers includes class AB and class D devices.

Compandors and audio amplifiers from ON Semiconductor deliver low noise expandor and amplifier functions for audio signals, within the low power premium audio headset subsystems found in today's automotive market.

High Speed and Fault Tolerant CAN Protection

The Controller Area Network (CAN) is a serial communications protocol designed for providing reliable high-speed data transmission in harsh environments. CAN system designers face the challenges of complying with EMI and ESD standards, while delivering reliable subsystems to the automotive market.

CAN bus protection circuits, such as the NUP2105, supplement the noise immunity level of CAN transceivers, while improving the reliability of the CAN module. The NUP2105 provides bidirectional protection for both lines of high-speed and fault tolerant CAN buses, complying with the IEC-61000 standards and dissipating up to 350 W peak power per line.

The NUP2105 provides this high level of protection with capacitance of only 30 pF maximum, enabling maximum data transmission speed. And by combining four protection elements in a single package, the device helps maintain highly reliable, compact electronic subsystems.

Pre-Drivers for LED Head Lamps

The emergence of automotive LED lighting enables the development of differentiating features, which can be delivered in subsystems with vastly enhanced reliability. These subsystems require advanced electronics to control and monitor the actual LEDs.

To help ease the design challenges inherent in the use of LEDs in head lamps, ON Semiconductor has introduced the NCV7513 FLEXMOS™ Hex Low-Side MOSFET Pre-Driver, which has been specifically designed to drive MOSFETs with lamp loads. This automotive grade pre-driver provides an unprecedented level of flexibility, by providing channel-specific control, fault-monitoring, and status reporting.

The NCV7513 drives NTD3055 MOSFETs. These 60 V devices provide 12 A of drive capability with 94 m W maximum R DS(ON) , in a space efficient DPAK package.

This LED head lamp subsystem also utilizes the CS5171 Boost Regulator, which combines high frequency operation of 280 kHz, with a highly integrated regulator circuit, resulting in an extremely compact power solution. The device provides peak switching current of 1.5 A with frequency synchronization capability, overcurrent protection, and thermal shutdown with hysteresis.

Ignition Coil Drivers

For Coil-on-Plug and Driver Coil-on-Plug ignition subsystems, IGBTs must provide fast switching speed with low conduction losses. ON Semiconductor's NGB8202N IGBT drives an ignition coil with a 1:100 turns ratio to achieve 40 KV at the spark plug.

Combining 20 A current capability with over-voltage protection, NGB8202N provides an integrated ignition coil driver component for a higher reliability circuit. And the simple microcontroller interface allows for easy implementation.

ON Semiconductor offers other IGBTs with current capability of 15 – 20 A and clamp voltages of 350 – 410 V, and delivers them in Pb-free DPAKs and D2PAKs.

Integrated Load Drivers

To operate door windows and locks, windshield wipers, and other features driven by small DC motors, control circuits will typically include a load driver, which gives a control signal from an embedded microcontroller the current it needs to drive a relay, solenoid, or inductive load.

When designing this type of load driver circuit, engineers face severe space constraints, high reliability needs, tight budgets, and a desire to use standard components and even entire standardized circuits.

ON Semiconductor's NUD3124 load driver provides 150 mA of drive current, while integrating the drive circuit into a single standard component. The device includes protection from inductive voltage spikes, thereby eliminating the need for separate free-wheeling diodes in the circuit. Since it accepts standard logic level signals, it can be controlled directly from microcontrollers or other standard logic, without an additional translation device.

ON Semiconductor offers additional load drivers, including the NUD3160. With a 60 V drain-to-source voltage, this device can prevent relays from activating during load-dump conditions, and is also suited for higher voltage trucking subsystems . NUD3124 and NUD3160 also comply with reverse battery, dual voltage jump start, and ESD requirements. Both devices are packaged in Pb-free, single and dual versions.

The integration levels of ON Semiconductor's load drivers eliminate the need for additional components, reducing circuit design time, reducing the bill-of-materials, and improving the drive circuit's overall reliability. And, since they drive a wide range of relays, as well as solenoids and inductive loads, they enable re-use of standard drive circuits for the many DC motor loads which are required in today's automotive market.

With the NUD3100 series, the resulting drive circuits will be standardized and re-usable, physically small, cost-effective, and highly reliable – while effectively delivering the necessary drive current.

Voltage Regulation and Supervision for Microcontrollers

As electronics in general and microcontrollers in particular continue to become more numerous in automobiles, designers must pay closer attention to the load that these subsystems place on the battery. Low quiescent current has become a key attribute of the ICs which regulate the voltage to the microcontroller.

The NCV8664 Low Dropout Linear Regulator delivers 150 mA with ±2.0% accuracy. The device combines careful management of light load current consumption with a low-leakage process to achieve typical quiescent current of only 22 µA; and maximum quiescent current of only 30 µA across the -40 to +85 ° C temperature range. This performance assists designers in meeting the new 100 µA maximum module quiescent current.

ON Semiconductor's portfolio includes LDO Regulators that deliver up to 1.5 A, and provide output voltages as low as 0.9 V.

For Supervisory circuits, ON offers devices such as the NCP302 Voltage Detector, accurate to ±2.0%, and including an externally programmable time delay generator. These combined features prevent erratic system reset operation. The device operates with a typical quiescent current of only 0.5 µA.

LED Drivers for Interior Lighting

Using LEDs in automotive lighting applications, delivers faster turn-on time, higher reliability and resistance to shock and vibration, and lower heat dissipation and power consumption, compared to incandescent bulbs.

Circuits using LEDs require a constant current flow, to maintain consistent brightness. Pulse-width-modulation to control dimming features is also frequently desired in today's market. Standard LED driver components can meet these needs in cost-effective, small form factors.

ON Semiconductor's NUD4001 LED driver maintains a constant current up to 350 mA, delivering improved accuracy, with the use of a single active component. The device tolerates input voltages up to 60 V, and maintains a constant light output during battery drain. Dimming features in lighting subsystems can be easily implemented by modulating a control signal.

ON Semiconductor is developing additional LED drivers that deliver constant currents of up to 2 A. In addition, ON offers switching regulators which can also control LED circuits.

For dome lights and other interior lights, tail lights, and directional lights using LEDs as the light source, ON Semiconductor's LED driver components deliver constant brightness and dimming control, with standard components that can reduce parts count and increase reliability.

Protected Switch Drivers for Small Motors

Today's automobiles include higher numbers of small motors, for subsystems ranging from pumps to antennas. ON Semiconductor's Self-Protected MOSFETs integrate protection features with power switches, enabling more robust, higher reliability drive circuits for small motors.

The NID5003N provides 20 A of drive, and includes short circuit protection, current limiting, over-voltage clamped protection, and ESD protection. The device also includes thermal shutdown with automatic restart, eliminating the need for a separate restart circuit.

Other devices in the family offer different combinations of R DS(on) and current capability.

ON Semiconductor's Self-Protected MOSFETs provide protection against faults, and eliminate the need for separate fuses, while delivering the performance needed to drive small motors in an automotive environment.

Driver for Outside Rear-View Mirrors

Outside rear-view mirrors have evolved from relatively simple assemblies with mechanical positioning controls, into complex electronic subsystems with motors for mirror positioning and assembly folding, turn indicators and puddle lights, and heating elements.  Designers must deliver all this functionality within tight space constraints.

Providing six independent high-side and low-side drivers, the NCV7708 Hex Driver provides the functionality and flexibility to drive various motor and LED combinations for outside rear-view mirror assemblies, and other complex automotive subsystems.  The device not only includes six separately controllable drivers, but incorporates freewheeling and clamping diodes.

A standard SPI interface allows the drivers to be configured for high-side, low-side, and H-bridge control, and also allows for comprehensive fault status to be reported.  The device can also enter a sleep mode in which it draws only 1 µA typical, to minimize power drain.

The advanced features and integrated functionality of the NCV7708 enable the design of smaller, more reliable circuits for use in complex motor and lighting drive subsystems.