TH8055
Single Wire CAN Transceiver
2.5 VBAT INPUT pin
Vehicle Battery Voltage
The transceiver is fully operational as described in Table Static Characteristics over the range 5 < V
BAT
< 18
volts as measured between the GND pin and the V
BAT
pin.
For 0 < V
BAT
< 4.95 volts, the bus is passive (not be driven dominant) and RxD is undriven (high), regardless
of the state of the TxD pin (undervoltage lockout).
The transceiver operates in normal mode when 18V > V
Bat IC
> 27V at 85°C for one minute. Other active
modes are possible until thermal shutdown (because of increased power dissipation), the transceiver does
not disturb normal communication.
2.6 CAN BUS input/output pin
Wave Shaping in normal and wake up mode
Wave shaping is incorporated into the transmitter to minimize EMI radiated emissions. An important
contributor to emissions is the rise and fall times during output transitions at the “corners” of the voltage
waveform. The resultant waveform is one half of a sin wave of frequency 50 - 65 kHz at the rising waveform
edge and one quarter of this sin wave at falling or trailing edge.
Wave Shaping in high speed mode
Wave shaping control of the rising and falling waveform edges are disabled during high speed mode. EMI
emissions requirements are waived during this mode. The waveform rise time in this mode is less than one
µs.
Short circuits
If the CAN BUS pin is shorted to ground for any duration of time, the current is limited as specified in table
“static characteristics” and an over temperature shut down circuit disables the output high side drive source
transistor before the local die temperature exceeds the damage limit threshold.
Loss of ground
In case of a valid loss of ground condition, the LOAD pin is switched into high impedance state. The CANH
transmission is continued until the undervoltage lock out voltage threshold is detected.
Loss of battery
In case of loss of battery (VBAT = 0 or open) the transceiver do not disturb bus communication. The
maximum reverse current into power supply system doesn‘t exceed 1mA.
TH8055 - Datasheet
3901008055
Page 6 of 20
May 2004
Rev 005
MELEXIS [ Melexis Microelectronic Systems ]
