Skip to main content

We use cookies to understand how you use our site and improve your experience. See our Privacy Policy.

PCA9557DR

8-Bit I/O Expander

The PCA9557DR is a 8-bit i/o expander from Texas Instruments. View the full PCA9557DR datasheet below including key specifications, electrical characteristics, absolute maximum ratings.

PCA9557DR shares its datasheet with PCA9557, whose page lists every part number it covers.

Official PCA9557DR datasheet (PDF) — the source this page was extracted from.

Manufacturer

Texas Instruments

Category

8-Bit I/O Expander

PCA9557DR Key Specifications

ParameterValue
Standby supply current (ICC)0.25 μA typ, 0.9 μA max at VCC = 3.6 V, fSCL = 0 kHz
Operating supply current12 μA typ, 22 μA max at VCC = 3.6 V, fSCL = 400 kHz
Power-on reset voltage (VPOR)1.65 V typ, 2.1 V max
P-port IOL8 mA min at VOL = 0.55 V, 10 mA min at VOL = 0.7 V (VCC 2.3–5.5 V)
SDA IOL3 mA min at VOL = 0.4 V (VCC 2.3–5.5 V)
Input leakage (P port)1 μA max
Input capacitanceSCL 4 pF typ; SDA 5.5 pF typ; P port 7.5 pF typ
Output data valid from SCL250 ns max (P0), 200 ns max (P1–P7)

PCA9557DR Overview

Part: PCA9557 — Texas Instruments

Type: I2C/SMBus 8-bit I/O Expander

Description: Remote 8-bit I2C and SMBus I/O expander with reset and configuration registers, 2.3–5.5 V supply, 400 kHz Fast-mode I2C, 5 V tolerant I/Os and 1 μA maximum standby current.

Operating Conditions:

  • Supply voltage: 2.3–5.5 V
  • Operating temperature: -40 to 85 °C
  • I2C clock: up to 400 kHz (Fast mode)
  • P-port output current: IOL max 25 mA (P7–P0); IOH max -10 mA (P7–P1)

Absolute Maximum Ratings:

  • Max supply voltage: 6 V (VCC); input and output voltage max 6 V
  • Continuous output low current: 50 mA; continuous output high current: -50 mA
  • Continuous current through VCC: 160 mA; through GND: -250 mA
  • Storage temperature: -65 to 150 °C

Key Specs:

  • Standby supply current (ICC): 0.25 μA typ, 0.9 μA max at VCC = 3.6 V, fSCL = 0 kHz
  • Operating supply current: 12 μA typ, 22 μA max at VCC = 3.6 V, fSCL = 400 kHz
  • Power-on reset voltage (VPOR): 1.65 V typ, 2.1 V max
  • P-port IOL: 8 mA min at VOL = 0.55 V, 10 mA min at VOL = 0.7 V (VCC 2.3–5.5 V)
  • SDA IOL: 3 mA min at VOL = 0.4 V (VCC 2.3–5.5 V)
  • Input leakage (P port): 1 μA max
  • Input capacitance: SCL 4 pF typ; SDA 5.5 pF typ; P port 7.5 pF typ
  • Output data valid from SCL: 250 ns max (P0), 200 ns max (P1–P7)

Features:

  • I2C to parallel port expander
  • 5 V tolerant I/O ports
  • Three hardware address pins allow up to eight devices on one bus
  • Input/output configuration register and polarity inversion register
  • Active-low reset input and internal power-on reset
  • High-impedance open-drain on P0
  • Powers up with all channels as inputs, with no glitch on power-up
  • Noise filter on SCL and SDA inputs
  • Latched outputs with high current drive for directly driving LEDs
  • Latch-up performance exceeds 100 mA per JESD 78, class II
  • ESD: HBM ±2000 V, CDM ±1000 V

Applications:

  • Telecom shelters: filter units
  • Servers
  • Routers (telecom switching equipment)
  • Personal computers
  • Personal electronics
  • Industrial automation
  • Products with limited GPIO

Package:

  • D (SOIC, 16) – 9.9 mm × 6 mm
  • DB (SSOP, 16) – 6.2 mm × 7.8 mm
  • DGV (TVSOP, 16) – 3.6 mm × 6.4 mm
  • PW (TSSOP, 16) – 5 mm × 6.4 mm
  • RGY (VQFN, 16) – 4 mm × 3.5 mm
  • RGV (VQFN, 16) – 4 mm × 4 mm

PCA9557DR Features

  • Low standby current consumption of 1μA maximum
  • I 2 C to parallel port expander
  • Operating power-supply voltage range of 2.3V to 5.5V
  • 5V Tolerant I/O ports
  • 400kHz Fast I 2 C bus
  • Three hardware address pins allow for use of up to eight devices on I 2 C/SMBus
  • Lower-voltage higher-performance migration path for PCA9556
  • Input and output configuration register
  • Polarity inversion register
  • Active-low reset input
  • Internal power-on reset
  • High-impedance open drain on P0
  • Power up with all channels configured as inputs
  • No glitch on power up
  • Noise filter on SCL or SDA inputs
  • Latched outputs with high current drive maximum capability for directly driving LEDs
  • Latch-up performance exceeds 100mA per JESD 78, class II
  • ESD protection exceeds JESD 22
  • -2000V Human-body model (A114-A)
  • -200V Machine model (A115-A)
  • -1000V Charged-device model (C101)

PCA9557DR Applications

PCA9557DR Pin Configuration

Figure 4-1. D, DB, DGV, PW Package, 16-Pin SOIC, SSOP, TVSOP, or TSSOP (Top View)

Figure 4-2. RGY or RGV Package, 16-Pin VQFN or VQFN (Top View)

Table 4-1. Pin Functions

PIN - NAMEPIN - NO.TYPE (1)DESCRIPTION
SCL1ISerial clock bus. Connect to V CC through a pullup resistor.
SDA2I/OSerial data bus. Connect to V CC through a pullup resistor.
A03IAddress input. Connect directly to V CC or ground.
A14IAddress input. Connect directly to V CC or ground.
A25IAddress input. Connect directly to V CC or ground.
P06I/OP-port input/output. High impedance open-drain design structure. Connect to V CC through a pullup resistor.
P17I/OP-port input/output. Push-pull design structure
GND8GGround
P29I/OP-port input/output. Push-pull design structure
P310I/OP-port input/output. Push-pull design structure
P411I/OP-port input/output. Push-pull design structure
P512I/OP-port input/output. Push-pull design structure
P613I/OP-port input/output. Push-pull design structure
P714I/OP-port input/output. Push-pull design structure
RESET15IActive-low reset input. Connect to V CC through a pullup resistor if no active connection is used.
V CC16PSupply voltage

(1) I = input, O = output, P = power, G = Ground

Table 4-1. Pin Functions

Figure 4-3. RGV Package, 16-Pin QFN (Top View)

Table 4-2. Pin Functions, RGV

PIN - NAMEPIN - NO.TYPE (1)DESCRIPTION
A01IAddress input. Connect directly to V CC or ground.
A12IAddress input. Connect directly to V CC or ground.
A23IAddress input. Connect directly to V CC or ground.
P04I/OP-port input/output. High impedance open-drain design structure. Connect to V CC through a pullup resistor.
P15I/OP-port input/output. Push-pull design structure
GND6GGround
P27I/OP-port input/output. Push-pull design structure
P38I/OP-port input/output. Push-pull design structure
P49I/OP-port input/output. Push-pull design structure
P510I/OP-port input/output. Push-pull design structure
P611I/OP-port input/output. Push-pull design structure
P712I/OP-port input/output. Push-pull design structure
RESET13IActive-low reset input. Connect to V CC through a pullup resistor if no active connection is used.
V CC14PSupply voltage
SCL15ISerial clock bus. Connect to V CC through a pullup resistor.
SDA16I/OSerial data bus. Connect to V CC through a pullup resistor.

(1) I = input, O = output, P = power, G = Ground

PCA9557DR Electrical Characteristics

over recommended operating free-air temperature range (unless otherwise noted)

PARAMETERPARAMETERTEST CONDITIONSVCCMINTYP (1)MAXUNIT
V IKInput diode clamp voltageI I = -18mA2.3V to 5.5V-1.2V
V PORPower-on reset voltage
(3)		V I = V CC or GND, I O = 0
I OH = -8mA		V POR
2.3V
3V
4.5V
4.75V		1.8
2.6
3
4.1		1.652.1V
V OHP-port high-level output voltageI OH = -10mA2.3V
3V
4.5V
4.75V		1.5
2.5
3
4		V
SDAV OL = 0.4V
V OL = 0.5V		2.3V to 5.5V3
8		20
I OLP port (2)V OL = 0.55V
V OL = 0.7V		2.3V to 5.5V8
10		20
24		mA
P port, except for P0 (2)V OH = 2.3V2.3V to 5.5V-4mA
I OHP0 (2)V OH = 4.6V4.6V to 5.5V1
SCL, SDAV OH = 3.3V3.3V to 5.5V
2.3V to 5.5V		1
±1		μA
I IA2-A0, RESETV I = V CC or GND±1μA
I IHP portV I = V CC2.3V to 5.5V1μA
I ILP portV I = GND2.3V to 5.5V
5.5V		191
25		μA
V I = V CC or GND, I O = 0, I/O = inputs, f = 400 kHz3.6V1222
SCL2.7V820
Operating mode5.5V1.55
I CCV I = V CC or GND, I O = 0, I/O = inputs, f = 100 kHz3.6V14μA
SCL2.7V
5.5V		0.6
0.25		3
1
Standby modeV I = V CC or GND, I O = 0, I/O =3.6V0.250.9
inputs, f SCL = 0 kHz2.7V0.20.8

PCA9557

over recommended operating free-air temperature range (unless otherwise noted)

PARAMETERPARAMETERTEST CONDITIONSVCCMINTYP (1)MAXUNIT
ΔI CCAdditional current in standby modeOne input at V CC - 0.6 V, Other inputs at V CC or GND2.3V to 5.5V0.2mA
ΔI CCEvery LED I/O at V I = 4.3 V, f SCL = 0 kHz5.5V0.4mA
C ISCLV I = V CC or GND2.3V to 5.5 V46pF
C ioSDAV IO = V CC or GND2.3V to 5.5V5.58pF
C ioP portV IO = V CC or GND2.3V to 5.5V7.59.5pF
  • (1) All typical values are at nominal supply voltage (2.5, 3.3, or 5V VCC) and TA = 25°C.
  • (2) Each I/O must be externally limited to a maximum of 25mA, and the P port (P7-P0) must be limited to a maximum current of 200mA.

(3) The total current sourced by all I/Os must be limited to 85mA per bit.

PCA9557DR Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted) see (1)

MINMAXUNIT
V CCSupply voltageSupply voltage-0.56V
V IInput voltage (2)Input voltage (2)-0.56V
V OOutput voltage (2)Output voltage (2)-0.56V
I IKInput clamp currentV I < 0-20mA
I OKOutput clamp currentV O < 0-20mA
I IOKInput/output clamp currentV O < 0 or V O > V CC-20μA
I OLContinuous output low currentV O = 0 to V CC50mA
I OHContinuous output high currentV O = 0 to V CC-50mA
I CCContinuous current through GNDContinuous current through GND-250mA
I CCContinuous current through V CCContinuous current through V CC160mA
T stgStorage temperatureStorage temperature-65150°C

PCA9557DR Recommended Operating Conditions

MINMAXUNIT
V CCSupply voltageSupply voltage2.35.5V
V IHHigh-level input voltageSCL, SDA0.7 × V CC5.5V
A2-A0, P7-P0, RESET2.25.5V
V ILSCL, SDA-0.50.3 × V CCV
Low-level input voltageA2-A0, P7-P0, (RESET V CC > 2.4V)-0.50.8V
RESET V CC ≤ 2.4V-0.50.75V
I OHHigh-level output currentP7-P1-10mA
I OLLow-level output currentP7-P025mA
T AOperating free-air temperatureOperating free-air temperature-4085°C

www.ti.com

PCA9557DR Thermal Information

over operating free-air temperature range (unless otherwise noted)

PCA9557PCA9557PCA9557PCA9557PCA9557PCA9557
THERMAL METRIC (1)THERMAL METRIC (1)D (SSOP)DB (SSOP)DGV (SSOP)PW (SSOP)RGV (VQFN)RGY (VQFN)UNIT
16 PINS16 PINS16 PINS16 PINS16 PINS16 PINS
R θJAJunction-to-ambient thermal resistance77.28212098.044.547°C/W
R θJC(top)Junction-to-case (top) thermal resistance40.030.740.1°C/W
R θJBJunction-to-board thermal resistance39.252.720.2°C/W
ψ JTJunction-to-top characterization parameter6.51.00.9°C/W
ψ JBJunction-to-board characterization parameter38.852.120.2°C/W
R θJC(bot)Junction-to-case (bottom) thermal resistanceN/AN/A5.7°C/W

PCA9557DR Typical Application

Figure 8-1 shows an application in which the PCA9557 can be used.

PCA9557DR Package Information

PART NUMBERPACKAGE (1)PACKAGE SIZE (2)
PCA9557D (SOIC, 16)9.9mm × 6mm
PCA9557DB (SSOP, 16)6.2mm × 7.8mm
PCA9557DGV (TVSOP, 16)3.6mm × 6.4mm
PCA9557PW (TSSOP, 16)5mm × 6.4mm
PCA9557RGY (VQFN, 16)4mm × 3.5mm
PCA9557RGV (VQFN, 16)4mm × 4mm
  • (1) For more information, see Section 11.
  • (2) The package size (length × width) is a nominal value and includes pins, where applicable.

Logic Diagram

www.ti.com

More datasheets

All Texas Instruments datasheets (2,442)

Data on this page is extracted from publicly available manufacturer datasheets using automated tools including AI. It may contain errors or omissions. Always verify specifications against the official manufacturer datasheet before making design or purchasing decisions. See our Terms of Service. Rights holders can submit a takedown request.

Ask your AI agent about the PCA9557DR

Connect SheetsData to Claude, Cursor, Codex or any MCP client and your agent reads this datasheet for you: pinout, limits, register maps and design checks, with the numbers taken from the PDF.

claude mcp add --transport http sheetsdata https://mcp.sheetsdata.com/mcp

Then ask: "Can the PCA9557DR run from my 12 V rail? Check it against the datasheet limits."

Create a free account $2 of usage every month, no card needed.