MCZ33989EG Freescale Semiconductor, MCZ33989EG Datasheet - Page 53

• Manufacturer Part Number: MCZ33989EG
• Description: IC SYSTEM BASIS CHIP CAN 28-SOIC
• Manufacturer: Freescale Semiconductor

Specifications of MCZ33989EG

• Applications: *
• Interface: *
• Voltage - Supply: *
• Package / Case: 28-SOIC (7.5mm Width)
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Table 35. Current in Case of Bus Short Conditions
Notes
receive anything on RX, so the CAN protocol handler inside
the MCU increases its TEC «transmit error counter» by 8.The
sender node keeps driving TX in dominant until it reaches the
error passive level (TEC=128).
Analog Integrated Circuit Device Data
Freescale Semiconductor
34.
No failure
CANH line to gnd
CANH line to 5 V
CANH line to +VBAT
CANL line to gnd
CANL line to 5 V
CANL line to VBAT
CANH line shorted to
CANL line
The sender node drives TX and the CAN bus, but doesn’t
For the failure case which leads to loss of communication and current flow for a very short time period as illustrated in
instance for CANH to gnd, the impact of the peak current on the V2 voltage regulator is very limited. The TX, RX, and CAN signal in the
figure are placed in a CANH to CANL short circuit condition.
Condition
current
I term
150
32
55
50
0
0
0
0
peak current (mA)
current
-150
I_H
150
-55
Figure 45. CANH to CANL Short Circuit Condition
70
0
0
0
0
current
-150
-240
-70
I-L
50
0
0
0
0
Normal communication.
No communication. Current flowing from V2 pin, during CAN driver dominant
state.
communication OK.
communication OK.
communication OK.
no communication
no communication
no communication
(34)
(23 bits in recessive). Then the sender nodes drive the bus
and send only 1 dominant bit, and as nothing is received on
RX, the TEC is incremental by 8. After TX is driven 15 times,
the TEC reaches 255: then the node is in the BUS OFF state.
occurrences of 11 recessive bits (1.408 ms at 1MBauds) in
order to recover and be able to transmit again.
When it is in error passive, it sends a passive error frame
When the node is in the BUS OFF state, it needs 128
(34)
(34)
(34)
Comment
SUPPLEMENTAL APPLICATION NOTES
TYPICAL APPLICATIONS
Figure
45. So for
33989
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