PCA9525D NXP [NXP Semiconductors], PCA9525D Datasheet - Page 7

• Manufacturer Part Number: PCA9525D
• Description: Simple 2-wire bus buffer
• Manufacturer: NXP [NXP Semiconductors]

NXP Semiconductors
PCA9525
Product data sheet
Fig 5.
Fig 7.
(mV)
V
OL
(V)
V
100
I
80
60
40
20
5
4
3
2
1
0
0
2
T
0
T
pull-up resistance
Typical input levels versus supply voltage
Typical LOW-level output voltage versus
amb
amb
V
DD
= 25 °C
= 25 °C
= 5.5 V
2.7 V
9.1 Bidirectional data buffer
2
3
V
V
V
lock
IH
IL
The bidirectional data buffer will determine which side has first fallen below V
that side of the buffer control over the direction of the buffer. For the purpose of this one
LOW-going pulse, that side now becomes the ‘input’ (be it SDA_IN or SDA_OUT).
When the ‘input’ side falls to near V
LOW. It will continue to hold the ‘output’ low until the ‘input’ exceeds V
‘output’ is released and will rise as fast as it is permitted by the load and pull-up to which it
is attached. (Assuming, of course, that the ‘output’ is not otherwise held LOW by some
other device on the bus on that side of the buffer.)
When the ‘input’ side again exceeds V
At this point, if the ‘output’ side was being held LOW (< V
immediately gain control and now become the ‘input’. What was the ‘input’ will now
become the ‘output’, and the process will repeat as above, but in the opposite direction.
4
4
6
5
All information provided in this document is subject to legal disclaimers.
8
V
R
002aaf333
002aaf335
DD
PU
(V)
(kΩ)
Rev. 1 — 25 February 2011
10
6
Fig 6.
Fig 8.
IL
V
, it will begin to drive the ‘output’ side of the buffer
I(hys)
(V)
unlock
(mV)
V
1000
OL
800
600
400
200
300
200
100
0
0
−50
, it will release its control of the buffer direction.
2
Typical V
voltage
I
Typical LOW-level output voltage versus
ambient temperature
OL
= 4 mA
T
V
amb
DD
= 5.5 V
= +85 °C
IH
3
0
2.7 V
+25 °C
−40 °C
− V
IL
lock
hysteresis versus supply
) by another device, it will
50
4
Simple 2-wire bus buffer
100
IH
PCA9525
5
© NXP B.V. 2011. All rights reserved.
at which point the
T
V
amb
002aaf334
002aaf336
DD
(V)
(C)
lock
150
6
and give
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