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PCA9557D

Every spec below is cited to the manufacturer datasheet. Pick your exact ordering code, compare the closest alternatives, then ask the assistant what it means for your design.

00 — Overview

What the PCA9557D family does

The PCA9557 is an 8-bit I2C-bus and SMBus I/O port expander with reset, available in SO16, TSSOP16, and HVQFN16 packages across commercial and industrial temperature ranges. It features an operating voltage of 2.3V to 5.5V, supports clock frequencies from 0kHz to 400kHz, and includes internal power-on reset with active-low reset input. The device offers high-impedance open-drain outputs, 5V tolerant inputs, and noise filtering on SCL/SDA lines. Engineers typically use this part for parallel input/output expansion in SMBus and I2C-bus applications, enabling system masters to configure channels as inputs or outputs while managing polarity inversion and reset functions efficiently.

Next step
Start building with PCA9557D → Every number above is cited straight from the datasheet — ask what they mean for your design, and the assistant answers from the same source documents.
Ordering code:
01 — Key specifications

PCA9557BS datasheet parameters

ParameterMinTypMaxConditionsSource
quiescent current — 19 µA 25 µA operating mode; VDD = 5.5 V; no load; fSCL = 100 kHz; idd; Supplies NXP datasheet, p. 15 — Table 10. Static characteristics
output current 8 mA 10 mA — VOL = 5.5 V; VDD = 2.3 V; iol; I/Os NXP datasheet, p. 15 — Table 10. Static characteristics
supply voltage range 2.3 V — 5.5 V vdd; Supplies NXP datasheet, p. 15 — Table 10. Static characteristics
operating temperature (abs max) -40 °C — 85 °C operating; tamb; Limiting values NXP datasheet, p. 14 — Table 9. Limiting values
power dissipation (abs max) — — 200 mW ptot; Limiting values NXP datasheet, p. 14 — Table 9. Limiting values
standby current — 250 nA 1 µA standby mode; VDD = 5.5 V; no load; VI = VDD; fSCL = 0 kHz; I/O = inputs; istbh; Supplies NXP datasheet, p. 15 — Table 10. Static characteristics
input capacitance — 3.7 pF 5 pF ci; I/Os NXP datasheet, p. 15 — Table 10. Static characteristics
output capacitance — 3.7 pF 5 pF co; I/Os NXP datasheet, p. 15 — Table 10. Static characteristics
propagation delay 200 ns — 250 ns data output valid time tv(Q); IO0: 250 ns, IO1 to IO7: 200 ns NXP datasheet, p. 16 — Port timing
data rate — 400 kbps — fast-mode I2C-bus, fSCL max NXP datasheet, p. 16 — Table 11. Dynamic characteristics
rise time — — 1 µs tr NXP datasheet, p. 16 — Table 11. Dynamic characteristics
fall time — — 300 ns tf NXP datasheet, p. 16 — Table 11. Dynamic characteristics
channel count — 8 — 8-bit input port register and 8-bit output port register; I/O pins IO0 to IO7 NXP datasheet, p. 1
01 — Key specifications

PCA9557D datasheet parameters

ParameterMinTypMaxConditionsSource
quiescent current — 19 µA 25 µA operating mode; VDD = 5.5 V; no load; fSCL = 100 kHz; idd; Supplies NXP datasheet, p. 15 — Table 10. Static characteristics
output current 8 mA 10 mA — VOL = 5.5 V; VDD = 2.3 V; iol; I/Os NXP datasheet, p. 15 — Table 10. Static characteristics
supply voltage range 2.3 V — 5.5 V vdd; Supplies NXP datasheet, p. 15 — Table 10. Static characteristics
operating temperature (abs max) -40 °C — 85 °C operating; tamb; Limiting values NXP datasheet, p. 14 — Table 9. Limiting values
power dissipation (abs max) — — 200 mW ptot; Limiting values NXP datasheet, p. 14 — Table 9. Limiting values
standby current — 250 nA 1 µA standby mode; VDD = 5.5 V; no load; VI = VDD; fSCL = 0 kHz; I/O = inputs; istbh; Supplies NXP datasheet, p. 15 — Table 10. Static characteristics
input capacitance — 3.7 pF 5 pF ci; I/Os NXP datasheet, p. 15 — Table 10. Static characteristics
output capacitance — 3.7 pF 5 pF co; I/Os NXP datasheet, p. 15 — Table 10. Static characteristics
propagation delay 200 ns — 250 ns data output valid time tv(Q); IO0: 250 ns, IO1 to IO7: 200 ns NXP datasheet, p. 16 — Port timing
data rate — 400 kbps — fast-mode I2C-bus, fSCL max NXP datasheet, p. 16 — Table 11. Dynamic characteristics
rise time — — 1 µs tr NXP datasheet, p. 16 — Table 11. Dynamic characteristics
fall time — — 300 ns tf NXP datasheet, p. 16 — Table 11. Dynamic characteristics
channel count — 8 — 8-bit input port register and 8-bit output port register; I/O pins IO0 to IO7 NXP datasheet, p. 1
01 — Key specifications

PCA9557PW datasheet parameters

ParameterMinTypMaxConditionsSource
quiescent current — 19 µA 25 µA operating mode; VDD = 5.5 V; no load; fSCL = 100 kHz; idd; Supplies NXP datasheet, p. 15 — Table 10. Static characteristics
output current 8 mA 10 mA — VOL = 5.5 V; VDD = 2.3 V; iol; I/Os NXP datasheet, p. 15 — Table 10. Static characteristics
supply voltage range 2.3 V — 5.5 V vdd; Supplies NXP datasheet, p. 15 — Table 10. Static characteristics
operating temperature (abs max) -40 °C — 85 °C operating; tamb; Limiting values NXP datasheet, p. 14 — Table 9. Limiting values
power dissipation (abs max) — — 200 mW ptot; Limiting values NXP datasheet, p. 14 — Table 9. Limiting values
standby current — 250 nA 1 µA standby mode; VDD = 5.5 V; no load; VI = VDD; fSCL = 0 kHz; I/O = inputs; istbh; Supplies NXP datasheet, p. 15 — Table 10. Static characteristics
input capacitance — 3.7 pF 5 pF ci; I/Os NXP datasheet, p. 15 — Table 10. Static characteristics
output capacitance — 3.7 pF 5 pF co; I/Os NXP datasheet, p. 15 — Table 10. Static characteristics
propagation delay 200 ns — 250 ns data output valid time tv(Q); IO0: 250 ns, IO1 to IO7: 200 ns NXP datasheet, p. 16 — Port timing
data rate — 400 kbps — fast-mode I2C-bus, fSCL max NXP datasheet, p. 16 — Table 11. Dynamic characteristics
rise time — — 1 µs tr NXP datasheet, p. 16 — Table 11. Dynamic characteristics
fall time — — 300 ns tf NXP datasheet, p. 16 — Table 11. Dynamic characteristics
channel count — 8 — 8-bit input port register and 8-bit output port register; I/O pins IO0 to IO7 NXP datasheet, p. 1
03 — Alternatives

Closest matches to PCA9557D

SN65HVD3082E 3.1× higher propagation delay, 2.0× lower data rate, 1.9× higher input capacitance
PCA9509 2.1× lower propagation delay, 2.0× lower data rate, 2.0× higher output current
PCA9517D 2.0× lower power dissipation, 1.6× higher input capacitance, 1.6× higher output capacitance
ADM2483BRW 4.6× higher output current, 2.5× lower rise time, 1.9× higher propagation delay
MCP4017 2.4× higher quiescent current, 1.9× higher operating temperature, 1.1× higher supply voltage range
MCP23017 6.7× higher fall time, 4.2× higher data rate, 4.0× higher standby current
GM3085E 7.4× higher quiescent current, 5.1× higher output current, 2.5× higher data rate
MAX3232 15.8× higher quiescent current, 3.5× higher output current, 1.6× lower data rate
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