Datasheet

PCA9600 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 5 — 5 May 2011 6 of 31
NXP Semiconductors
PCA9600
Dual bidirectional bus buffer
When the device driving the PCA9600 is an I
2
C-bus compatible device, then the
PCA9600 is an improvement on the P82B96 as shown in Table 4
. There will always be
exceptions however, and if the device driving the bus buffer is not I
2
C-bus compatible
(e.g., you need to use the micro already in the system and bit-bang using two GPIO pins)
then here are some considerations that would point to using the P82B96 instead:
• When the pull-up must be the weakest one possible. The spec is 200 μA for P82B96,
but it typically works even below that. And if designing for a temperature range −40 °C
up to +60 °C, then the driver when sinking 200 μA only needs to drive a guaranteed
low of 0.55 V. For the PCA9600, over that same temperature range and when sinking
1.3 mA (at −40 °C), the device driving the bus buffer must provide the required low of
0.425 V.
• When the lower operating temperature range is restricted (say 0 °C). The P82B96
larger SX voltage levels then make a better typical match with the driver, even when
the supply is as low as 3.3 V.
For an I
2
C-bus compliant driver on 3.3 V the P82B96 is required to guarantee a bus
low that is below 0.83 V. P82B96 guarantees that with a 200 μA pull-up.
• When the operating temperature range is restricted at both limits. An I
2
C driver's
typical output is well below 0.4 V and the P82B96 typically requires 0.6 V input even
at +60 °C, so there is a reasonable margin. The PCA9600 requires a typical input low
of 0.5 V so its typical margin is smaller. At 0 °C the driver requires a typical input low
of 1.16 V and P82B96 provides 0.75 V, so again the typical margin is already quite big
and even though PCA9600 is better, providing 0.7 V, that difference is not big.
8. Limiting values
[1] See also Section 10.2 “Negative undershoot below absolute minimum value”.
Table 5. Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134).
Voltages with respect to pin GND.
Symbol Parameter Conditions Min Max Unit
V
CC
supply voltage V
CC
to GND −0.3 +18 V
V
I2C-bus
I
2
C-bus voltage SX and SY;
I
2
C-bus SDA or SCL
−0.3 +18 V
V
O
output voltage TX and TY;
buffered output
[1]
−0.3 +18 V
V
I
input voltage RX and RY;
receive input
[1]
−0.3 +18 V
I
I2C-bus
I
2
C-bus current SX and SY;
I
2
C-bus SDA or SCL
- 250 mA
P
tot
total power dissipation - 300 mW
T
j
junction temperature operating range −40 +125 °C
T
stg
storage temperature −55 +125 °C
T
amb
ambient temperature operating −40 +85 °C