PCA9557 Series

8-bit 2.3- to 5.5-V I2C/SMBus I/O expander with reset & config registers

Catalog

8-bit 2.3- to 5.5-V I2C/SMBus I/O expander with reset & config registers

Part	Interface	Voltage - Supply [Min]	Voltage - Supply [Max]	Output Type	Clock Frequency	Current - Output Source/Sink [custom]	Current - Output Source/Sink [custom]	Mounting Type	Supplier Device Package	Number of I/O	Package / Case [x]	Package / Case	Package / Case [y]	Operating Temperature [Max]	Operating Temperature [Min]	Features	Package / Case [custom]	Package / Case [custom]
Texas Instruments PCA9557PW	I2C SMBus	2.3 V	5.5 V	Open Drain Push-Pull	400 kHz	10 mA	25 mA	Surface Mount	16-TSSOP	8	0.173 in	16-TSSOP	4.4 mm	85 °C	-40 °C	POR
Texas Instruments PCA9557D	I2C SMBus	2.3 V	5.5 V	Open Drain Push-Pull	400 kHz	10 mA	25 mA	Surface Mount	16-SOIC	8	0.154 in	16-SOIC	3.9 mm	85 °C	-40 °C	POR
Texas Instruments PCA9557PWT	I2C SMBus	2.3 V	5.5 V	Open Drain Push-Pull	400 kHz	10 mA	25 mA	Surface Mount	16-TSSOP	8	0.173 in	16-TSSOP	4.4 mm	85 °C	-40 °C	POR
Texas Instruments PCA9557DB	I2C SMBus	2.3 V	5.5 V	Open Drain Push-Pull	400 kHz	10 mA	25 mA	Surface Mount	16-SSOP	8		16-SSOP		85 °C	-40 °C	POR	0.209 in	5.3 mm
Texas Instruments PCA9557RGYR	I2C SMBus	2.3 V	5.5 V	Open Drain Push-Pull	400 kHz	10 mA	25 mA	Surface Mount	16-VQFN (4x3.5)	8		16-VFQFN Exposed Pad		85 °C	-40 °C	POR
Texas Instruments PCA9557DBR	I2C SMBus	2.3 V	5.5 V	Open Drain Push-Pull	400 kHz	10 mA	25 mA	Surface Mount	16-SSOP	8		16-SSOP		85 °C	-40 °C	POR	0.209 in	5.3 mm
Texas Instruments PCA9557DR	I2C SMBus	2.3 V	5.5 V	Open Drain Push-Pull	400 kHz	10 mA	25 mA	Surface Mount	16-SOIC	8	0.154 in	16-SOIC	3.9 mm	85 °C	-40 °C	POR

Catalog

8-bit 2.3- to 5.5-V I2C/SMBus I/O expander with reset & config registers

Key Features

• Low standby current consumption of 1µA maximumI2C to parallel port expanderOperating power-supply voltage range of 2.3V to 5.5V5V Tolerant I/O ports400kHz Fast I2C busThree hardware address pins allow for use of up to eight devices on I2C/SMBusLower-voltage higher-performance migration path for PCA9556Input and output configuration registerPolarity inversion registerActive-low reset inputInternal power-on resetHigh-impedance open drain on P0Power up with all channels configured as inputsNo glitch on power upNoise filter on SCL or SDA inputsLatched outputs with high current drive maximum capability for directly driving LEDsLatch-up performance exceeds 100mA per JESD 78, class IIESD protection exceeds JESD 222000V Human-body model (A114-A)200V Machine model (A115-A)1000V Charged-device model (C101)Low standby current consumption of 1µA maximumI2C to parallel port expanderOperating power-supply voltage range of 2.3V to 5.5V5V Tolerant I/O ports400kHz Fast I2C busThree hardware address pins allow for use of up to eight devices on I2C/SMBusLower-voltage higher-performance migration path for PCA9556Input and output configuration registerPolarity inversion registerActive-low reset inputInternal power-on resetHigh-impedance open drain on P0Power up with all channels configured as inputsNo glitch on power upNoise filter on SCL or SDA inputsLatched outputs with high current drive maximum capability for directly driving LEDsLatch-up performance exceeds 100mA per JESD 78, class IIESD protection exceeds JESD 222000V Human-body model (A114-A)200V Machine model (A115-A)1000V Charged-device model (C101)

Description

This 8-bit I/O expander for the two-line bidirectional bus (I2C) is designed for 2.3V to 5.5V VCC operation. The device provides general-purpose remote I/O expansion for most microcontroller families through the I2C interface [serial clock (SCL) and serial data (SDA)]. The PCA9557 consists of one 8-bit configuration (input or output selection), input port, output port, and polarity inversion (active-high) registers. At power on, the I/Os are configured as inputs. However, the system controller 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 or output register. The polarity of the input port register can be inverted with the polarity inversion register. All registers can be read by the system controller. The device outputs (latched) have high-current drive capability for directly driving LEDs. The device has low current consumption. The system controller can reset the PCA9557 in the event of a timeout or other improper operation by asserting a low in the active-low reset (RESET) input. The power-on reset puts the registers in their default state and initializes the I2C/SMBus state machine. Asserting RESET causes the same reset/initialization to occur without depowering the part. Three hardware pins (A0, A1, and A2) are used to program and vary the fixed I2C address, allowing up to eight devices to share the same I2C bus or SMBus. This 8-bit I/O expander for the two-line bidirectional bus (I2C) is designed for 2.3V to 5.5V VCC operation. The device provides general-purpose remote I/O expansion for most microcontroller families through the I2C interface [serial clock (SCL) and serial data (SDA)]. The PCA9557 consists of one 8-bit configuration (input or output selection), input port, output port, and polarity inversion (active-high) registers. At power on, the I/Os are configured as inputs. However, the system controller 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 or output register. The polarity of the input port register can be inverted with the polarity inversion register. All registers can be read by the system controller. The device outputs (latched) have high-current drive capability for directly driving LEDs. The device has low current consumption. The system controller can reset the PCA9557 in the event of a timeout or other improper operation by asserting a low in the active-low reset (RESET) input. The power-on reset puts the registers in their default state and initializes the I2C/SMBus state machine. Asserting RESET causes the same reset/initialization to occur without depowering the part. Three hardware pins (A0, A1, and A2) are used to program and vary the fixed I2C address, allowing up to eight devices to share the same I2C bus or SMBus.