PCA9538 Datasheet, PDF (1/29 Pages) NXP Semiconductors – 8-bit I2C and SMBus low power I/O port with interrupt and reset

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PCA9538
REMOTE 8-BIT I²C AND SMBus LOW-POWER I/O EXPANDER
WITH INTERRUPT OUTPUT, RESET, AND CONFIGURATION REGISTERS
SCPS126D – SEPTEMBER 2006 – REVISED MARCH 2007
FEATURES
• Low Standby Current Consumption of
1 µA Max
• I²C to Parallel Port Expander
• Open-Drain Active-Low Interrupt Output
• Active-Low Reset Input
• Operating Power-Supply Voltage Range of
2.3 V to 5.5 V
• 5-V Tolerant I/O Ports
• 400-kHz Fast I²C Bus
• Two Hardware Address Pins Allow up to Four
Devices on the I²C/SMBus
• Input/Output Configuration Register
• Polarity Inversion Register
• Power-Up With All Channels Configured as
Inputs
• No Glitch on Power Up
• Noise Filter on SCL/SDA Inputs
• Latched Outputs With High-Current Drive
Maximum Capability for Directly Driving LEDs
• Latch-Up Performance Exceeds 100 mA Per
JESD 78, Class II
• ESD Protection Exceeds JESD 22
– 2000-V Human-Body Model (A114-A)
– 200-V Machine Model (A115-A)
– 1000-V Charged-Device Model (C101)
DB, DBQ, DGV, DW, OR PW PACKAGE
(TOP VIEW)
RGV PACKAGE
(TOP VIEW)
RGT PACKAGE
(TOP VIEW)
A0 ¹
A1 ²
RESET ³
P0 ⁴
P1 ⁵
P2 ⁶
P3 ⁷
GND ⁸
16 _VCC
15 _SDA
14 _SCL
13 _INT
12 _P7
11 _P6
10 _P5
9 _P4
16 15 14 13
RESET 1
12 SCL
P0 2
11 INT
P1 3
10 P7
P2 4
9 P6
567 8
RESET
P0
P1
P2
16 15 14 13
1
12
2
11
3
10
4
9
567 8
SCL
INT
P7
P6
DESCRIPTION/ORDERING INFORMATION
This 8-bit I/O expander for the two-line bidirectional bus (I²C) is designed for 2.3-V to 5.5-V V_CC operation. It
provides general-purpose remote I/O expansion for most microcontroller families via the I²C interface [serial
clock (SCL), serial data (SDA)].
The PCA9538 consists of one 8-bit Configuration (input or output selection), Input Port, Output Port, and Polarity
Inversion (active high or active low) registers. At power on, the I/Os are configured as inputs. However, the
system master can enable the I/Os as either inputs or outputs by writing to the I/O configuration bits. The data
for each input or output is kept in the corresponding Input Port or Output Port register. The polarity of the Input
Port register can be inverted with the Polarity Inversion register. All registers can be read by the system master.
The system master can reset the PCA9538 in the event of a timeout or other improper operation by asserting a
low in the RESET input. The power-on reset puts the registers in their default state and initializes the I²C/SMBus
state machine. The RESET pin causes the same reset/initialization to occur without powering down the part.
The PCA9538 open-drain interrupt (INT) output is activated when any input state differs from its corresponding
Input Port register state and is used to indicate to the system master that an input state has changed.
INT can be connected to the interrupt input of a microcontroller. By sending an interrupt signal on this line, the
remote I/O can inform the microcontroller if there is incoming data on its ports without having to communicate via
the I²C bus. Thus, the PCA9538 can remain a simple slave device.
The device outputs (latched) have high-current drive capability for directly driving LEDs. It has low current
consumption.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2006–2007, Texas Instruments Incorporated