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Maxim’s power management IC reduces space and noise in instrument clusters.

Maxim chips help trim space requirements in dashboards

Whether design teams are trying to cram more features and functions into dashboards or striving to increase efficiency, design groups want chips that save space and reduce weight. Maxim Integrated Products is focusing on these challenges with a pair of products that reduce board space and let engineers transition to lighter-weight cabling.

Maxim unveiled two devices aimed at reducing space in cramped dashboards. The 3.12-GB/s Gigabit Multimedia Serial Link SerDes chipset lets designers of high-resolution automotive infotainment systems use lighter, less expensive coaxial cables. The other device, the MAX16993 power management IC (PMIC), squeezes three channels into a chip that can operate with smaller external components, cutting board space requirements in half.

The PMIC, designed primarily for instrument cluster and center stack displays, consumes just 25 μA of quiescent current, meeting automaker requirements that limit instrument cluster module consumption to less than 100 μA in standby mode. The chip integrates a high-switching-frequency controller and two output converters capable of 3 A each, reducing space requirements over discrete designs.

“Users can save more than 50% in board space versus using three separate dc-dc converters and larger external components,” said Dan Dempsey, Executive Director in the Automotive Business Unit at Maxim Integrated. “Running at 2.1 MHz lets designers use smaller inductors and capacitors. Instead of using parts packaged in metal cans, we let them use ceramic capacitors, which are much smaller.”

He noted that this frequency also helps electronic designers avoid interference with AM bands. Normally, dc-dc converters operate in lower frequencies so they must be shielded to avoid this interference. But at 2.1 MHz, all AM bandwidth noise is eliminated, Dempsey said. The PMIC also trims power consumption, which is getting increased attention as automakers struggle to meet tighter fuel consumption rules.

“As carmakers focus more on emissions and low power electronic components, more are using dc-dc converters instead of low dropout (LDO) regulators,” Dempsey said. “When you go from an LDO to a dc-dc converter, you’re going from somewhere around 50% efficiency to 80-90% efficiency.”

The three channels can be set to work with parts that have different voltages. For example, channels may be linked to conventional 5-volt ICs or to lower voltages like 3.3 V.

The SerDes chipset lets developers transition from the shielded twisted pair cables now common in infotainment systems to coax cables, which can trim cabling weight by 50%. It also extends cable lengths to 15 m (49 ft) to support rear-seat entertainment displays.

Each serializer and deserializer improves EMI performance by offering spread-spectrum capability without requiring an external spread-spectrum clock. The chipset can work with high-resolution center stack and rear-seat displays while also supporting megapixel camera systems. The chips can drive 1920 x 720 pixel displays with 24-bit color resolution.

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