Diagnostics chip integrates configurable automotive buses and power management functions

October 28, 2013 // By Paul Buckley
Fabless analog ASIC company, JVD Inc., has started volume production of the company's automotive integrated circuit, the JV700, an ODB-II Diagnostics Interface/Controller. 

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