AS8221

Data Sheet AS8221 F l e x R a y S t a n d a r d Tr a n s c e i v e r www.DataSheet4U.com 1 General Description This document is subjected to change without notice. The AS8221 is a high speed automotive bus driver fully conforming to the FlexRay Electrical Physical Layer Specification V2.1 Rev B. The AS8221 operates as a bi-directional interface between the FlexRay Communication Controller and the twisted-pair copper wiring. The AS8221 provides an optimized host controller interface consisting of three low-active pins. The Enable (EN) and Standby (STBN) input pins for mode handling by the microcontroller and the Error (ERRN) out pin where system, chip failures or status information are signalled to the microcontroller. Signalling logic high on the Enable and Standby pin the device will enter NORMAL mode in case no fault condition is given and in this mode the device is fully operational meaning FlexRay communication is possible. Additionally a RECEIVE-0NLY mode is implemented, which can be accessed by the microcontroller where only FlexRay streams can be received in order to avoid unwanted disturbances on the FlexRay bus while listening to the bus traffic. In the low-power modes (STANDBY and SLEEP mode) very low power consumption is achieved. In case of undervoltage at one of the supply voltages (VBAT, VCC, and VIO) the device will change its mode to a low-power mode (either STANDBY or SLEEP mode) and the device will signal an error accordingly. In case of low voltage is det...