LIN-I/O Follower

The UJA1023 is a stand-alone Local Interconnect Network (LIN) I/O follower that replaces basic components commonly used in electronic control units for input and output handling. The UJA1023 contains a LIN 2.0 controller, an integrated LIN transceiver which is LIN 2.0 / SAE J2602 compliant and LIN 1.3 compatible, a 30 kΩ termination resistor necessary for LIN-followers, and eight I/O ports which are configurable via the LIN bus.

An automatic bit rate synchronization circuit adapts to any (leader) bit rate between 1 kbit/s and 20 kbit/s. For this, an oscillator is integrated.

The LIN protocol will be handled autonomously and both Node Address (NAD) and LIN frame Identifier (ID) programming will be done by a leader request and an optional follower response message in combination with a daisy chain or plug coding function.

The eight bidirectional I/O pins are configurable via LIN bus messages and can have the following functions:

• Input:
  • Standard input pin
  • Local wake-up
  • Edge capturing on falling, rising or both edges
  • Analog input pin
  • Switch matrix (in combination with output pins
• Output:
  • Standard output pin as high-side driver, low-side driver or push-pull driver
  • Cyclic sense mode for local wake-up
  • PWM mode, for example, for back light illumination
  • Switch matrix (in combination with input pins)

On entering a low-power mode it is possible to hold the last output state or to change over to a user programmable output state. In case of a failure (e.g. LIN bus short to ground) the output changes over to a user programmable limp home output state and the low-power Limp home mode will be entered.

Due to the advanced low-power behavior the power consumption of the UJA1023 in low-power mode is minimal.