ZHCSKL7 December 2019 – December 2019 TCAN1044V
PRODUCTION DATA.
- 1 特性
- 2 應用
- 3 說明
- 4 修訂歷史記錄
- 5 Pin Configuration and Functions
-
6 Specifications
- Table 1. Absolute Maximum Ratings
- Table 2. ESD Ratings
- Table 3. ESD Ratings
- Table 4. Recommended Operating Conditions
- Table 5. Thermal Characteristics
- Table 6. Supply Characteristics
- Table 7. Dissipation Ratings
- Table 8. Electrical Characteristics
- Table 9. Switching Characteristics
- 6.1 Typical Characteristics
- 7 Parameter Measurement Information
-
8 Detailed Description
- 8.1 Overview
- 8.2 Functional Block Diagram
- 8.3 Feature Description
- 8.4 Device Functional Modes
- 9 Application and Implementation
- 10Power Supply Recommendations
- 11Layout
- 12器件和文檔支持
- 13機械、封裝和可訂購信息
8.3.3 TXD Dominant Timeout (DTO)
During normal mode, the only mode where the CAN driver is active, the TXD DTO circuit prevents the local node from blocking network communication in the event of a hardware or software failure where TXD is held dominant longer than the timeout period tTXD_DTO. The TXD DTO circuit is triggered by a falling edge on TXD. If no rising edge is seen before the timeout period of the circuit, tTXD_DTO, the CAN driver is disabled. This frees the bus for communication between other nodes on the network. The CAN driver is reactivated when a recessive signal is seen on the TXD pin, thus clearing the dominant time out. The receiver remains active and biased to VCC/2 and the RXD output reflects the activity on the CAN bus during the TXD DTO fault.
The minimum dominant TXD time allowed by the TXD DTO circuit limits the minimum possible transmitted data rate of the device. The CAN protocol allows a maximum of eleven successive dominant bits (on TXD) for the worst case, where five successive dominant bits are followed immediately by an error frame. The minimum transmitted data rate may be calculated using Equation 1.
Figure 14. Example Timing Diagram for TXD Dominant Timeout