USB charging controller connects any portable device to automotive supplies

October 17, 2013 // By Paul Buckley
Maxim has introduced the MAX16984 automotive DC-DC converter with USB charge emulator which uses a single IC to recognise and then charge any portable device (PD) directly from a vehicle battery.

Previously, PDs like smartphones and tablets could not be dependably charged from standard OEM USB ports in vehicles, according to Maxim. Long embedded USB cables cause a voltage drop and reduce charging current, causing a PD not to charge properly. Low-cost portable USB car chargers introduce RF interference. Tthe MAX16984 brings intelligent USB charging into an automobile and solves these problems.

The single-chip solution integrates all the functions of a traditional three-chip solution. MAX16984 combines a low EMI 5-V automotive-grade DC-DC converter capable of driving up to 2.5A with dynamic voltage adjustment, which is essential for charging contemporary PDs over long automotive embedded cables; a USB Battery Charging Specification v1.2-compliant charge emulator, which conducts the necessary handshake between the PD and upstream host instructing the PD to increase its charge current; and integrated ESD diodes and USB over-voltage protection switches, which provide robust fault protection. The result is the fastest and most reliable PD charging with the smallest solution size. The MAX16984 is suitable for automotive radios and navigation modules, embedded telematics and connectivity modules, and USB-dedicated charging ports.

The device operates from a voltage up to 28V and is protected from load dump transients up to 42V; integrated output adjustment eliminates cable voltage drop.

The MAX16984’s automotive USB function communicates with a connected PD and switches to low-power mode when not in use to reduce power consumption.  The device is the only USB protection IC with integrated ESD diodes, which prevent damage to the vehicle’s radio or peripheral components.

In 5 x 5 mm, 28-pin TQFN and QFND packages, the MAX16984 is AEC-Q100 qualified and specified over the -40°C to +125°C automotive temperature range.

 Maxim Integrated;