MENU

Diagnostics chip integrates configurable automotive buses and power management functions

Diagnostics chip integrates configurable automotive buses and power management functions

Technology News |
By eeNews Europe



Designed and produced for Launch Tech Co., Ltd, a leader in professional automotive diagnostics equipment, the JV700 is a custom analog ASIC that resides in a small dongle that plugs into the vehicle’s ODB-II connector (typically located under the dash). The JV700 incorporates all the critical analog functions required to interface and communicate through the ODB-II connector with all major automotive buses. The chip receives instructions to configure a complex array of low RDS(on) MOSFET switches that properly align the chip’s five bus transceivers to the correct ODB-II pins based on the vehicle’s make, model, year and VIN. The JV700 then communicates the vehicle information via a serial bus to a nearby microcontroller where the data is processed and communicated via Bluetooth to a cell phone or mobile computer for viewing.

The JV700 communicates with all of the standard ODB-II accessible Bus Protocols and can manage any three simultaneously:

  • ISO15765-4 (CAN)
  • ISO14230-4 (KWP2000)
  • ISO9141-2
  • J1850 VPW
  • J1850 PWM

The JV700 is packaged in a standard 48 pin QFN package. In addition to the switch matrix and five automotive bus transceivers, the chip also includes several power management elements (dc-dc converters and LDOs).

Launch Tech CTO, Oliver Zhang, said: “Without the JV700 Analog ASIC, we would not have been able to create this state of the art diagnosis system. Consumers can now check their own vehicles for DTC errors and clear the codes themselves.”

Diagnostic Trouble Code (DTCs) are how ODB-II identifies and communicates to technicians where and what on-board problems exist. The first number in the DTC indicates whether the code is an SAE generic code (applies to all ODB-II systems) or is specific to the vehicle manufacturer. The remaining three numbers provide information regarding the specific vehicle system and circuit. An analysis of a typical ODBII code is shown below.

While the communication protocol standards are universal, not every make and model uses the same pins on the ODB-II connector to access the information, making universal diagnosis all but impossible without the circuitry found in the JV700.

To further complicate diagnostic testing, there remain several pins in the ODB-II connector that are unspecified and their use is left to the vehicle manufacturer’s discretion.  These unassigned pins are available for use by the manufacturer for things  such as airbags, alarms, remotes, and more and their use varies widely among the world’s car manufacturers and even among different models produced by a single manufacturer.  The JV700 can connect and communicate with the unassigned pins to read and manage the peripheral information as well.

Once the JV700 orients its configuration for the appropriate make, model, year vehicle, the information it accesses is communication across a serial bus to a microcontroller and the results are then communicated wirelessly to be viewed on a cell phone or mobile computer via Bluetooth. A typical mobile phone display will look something like this:

Automotive environments require that additional protection, not typically required in more mainstream applications be designed into the IC. The JV700 incorporates all required protection features typically found in automotive semiconductors, including Reverse Battery Protection, Double-Battery Jump Start, which occurs when a tow truck or other service personnel use 24 V to jump-start a disabled vehicle or otherwise charge a dead battery, and high ESD Protection.

Visit JVD at www.jvdinc.com

If you enjoyed this article, you will like the following ones: don't miss them by subscribing to :    eeNews on Google News

Share:

Linked Articles
10s