PCA82C251 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 04 — 25 August 2011 4 of 17
NXP Semiconductors
PCA82C251
CAN transceiver for 24 V systems
LOW level. The microcontroller should react to this condition by switching the transceiver
back to normal operation (via pin 8). Because the receiver is slower in Standby mode, the
first message will be lost at higher bit rates.
[1] If another bus node is transmitting a dominant bit, then RXD is logic 0.
[2] X = don’t care.
9. Limiting values
[1] TXD is LOW. Short-circuit protection provided for slew rates up to 5 V/s for voltages above +30 V.
[2] Short-circuit applied when TXD is HIGH, followed by TXD switched to LOW.
[3] In accordance with “IEC 60747-1”. An alternative definition of virtual junction temperature is: T
vj
=T
amb
+P
d
R
th(vj-a)
, where R
th(j-a)
is a
fixed value to be used for the calculation of T
vj
. The rating for T
vj
limits the allowable combinations of power dissipation (P
d
) and ambient
temperature (T
amb
).
[4] Classification A: human body model; C = 100 pF; R = 1500 ; V = 2000 V.
[5] Classification B: machine model; C = 200 pF; R = 25 ; V = 200 V.
Table 4. Truth table of the CAN transceiver
Supply TXD CANH CANL Bus state RXD
4.5 V to 5.5 V 0 HIGH LOW dominant 0
4.5 V to 5.5 V 1 (or floating) floating floating recessive 1
[1]
4.5 V < V
CC
<5.5V X
[2]
floating if
V
Rs
>0.75V
CC
floating if
V
Rs
> 0.75V
CC
floating X
[1]
0V<V
CC
< 4.5 V floating floating floating floating X
[2]
Table 5. Pin Rs summary
Condition forced at pin Rs Mode Resulting voltage or current at pin Rs
V
Rs
>0.75V
CC
Standby I
Rs
<10A
10 A<I
Rs
<200A Slope control 0.4V
CC
<V
Rs
<0.6V
CC
V
Rs
<0.3V
CC
High-speed I
Rs
< 500 A
Table 6. Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134). All voltages are referenced to pin 2; positive input
current.
Symbol Parameter Conditions Min Max Unit
V
CC
supply voltage 0.3 +7.0 V
V
n
DC voltage at pins 1, 4, 5 and 8 0.3 V
CC
+0.3 V
V
6
DC voltage at pin 6 (CANL) 0 V < V
CC
< 5.5 V; TXD HIGH or floating 36 +36 V
0V<V
CC
< 5.5 V; no time limit
[1]
36 +36 V
0V<V
CC
< 5.5 V; no time limit
[2]
36 +36 V
V
7
DC voltage at pins 7 (CANH) 0 V < V
CC
< 5.5 V; no time limit 36 +36 V
V
trt
transient voltage at pins 6 and 7 see Figure 8 200 +200 V
T
stg
storage temperature 55 +150 C
T
amb
ambient temperature 40 +125 C
T
vj
virtual junction temperature
[3]
40 +150 C
V
ESD
electrostatic discharge voltage
[4]
2500 +2500 V
[5]
250 +250 V
