pca9539d NXP Semiconductors, pca9539d Datasheet - Page 11

• Manufacturer Part Number: pca9539d
• Description: 16-bit I2c And Smbus, Low Power I/o Port With Interrupt And Reset
• Manufacturer: NXP Semiconductors

Philips Semiconductors
TYPICAL APPLICATION
Minimizing I
When the I/Os are used to control LEDs, they are normally connected to V
diode, when the LED is off the I/O V
specified as I
Designs needing to minimize current consumption, such as battery power applications, should consider maintaining the I/O pins greater than or
equal to V
voltage by at least 1.2 V. Both of these methods maintain the I/O V
the LED is off.
2006 Sep 21
16-bit I
I/O port with interrupt and reset
(5 V)
V
DD
Figure 12. High value resistor in parallel with the LED
NOTE: Device address configured as 1110100 for this example
CONTROLLER
DD
MASTER
I/O
I/O
I/O
2
when the LED is off. Figure 12 shows a high value resistor in parallel with the LED. Figure 13 shows V
GND
0.0
0.1
0.6
C-bus and SMBus low power
DD
V
DD
, I/O
, I/O
, I/O
DD
in the DC characteristics table.
RESET
0.2
0.4
0.7
when the I/O is used to control LEDs
V
SDA
, I/O
, I/O
, and I/O
DD
SCL
LEDx
INT
0.3
0.5
, configured as outputs
, configured as inputs
10 k
1.0
to I/O
1.7
LED
IN
10 k
configured as inputs
is about 1.2 V less than V
100 k
10 k
V
DD
10 k
Figure 11. Typical application
SW02086
DD
RESET
A1
A0
SDA
INT
SCL
IN
. The supply current, I
PCA9539
V
at or above V
DD
11
V
SS
DD
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
1.0
1.1
1.3
1.4
1.5
1.6
1.7
1.2
through a resistor as shown in Figure 11. Since the LED acts as a
2 k
DD
Figure 13. Device supplied by a lower voltage
and prevents additional supply current consumption when
DD
, increases as V
NUMERIC
10 DIGIT
KEYPAD
100 k
( 3)
ALARM
(e.g. alarm system)
V
3.3 V
SUBSYSTEM 3
DD
LEDx
(e.g. temp sensor)
INT
SUBSYSTEM 1
IN
becomes lower than V
LED
DD
5 V
less than the LED supply
Controlled Switch
(e.g. CBT device)
ENABLE
PCA9539
Product data sheet
RESET
SUBSYSTEM 2
(e.g. counter)
A
B
SW02094
DD
SW02087
and is
V
DD