Low-voltage 16-bit I²C and SMBus I/O expander with interrupt output and configuration registers

The NCA9555-Q100 provides 16 bits of General Purpose Input/Output (GPIO) expansion for I²C-bus/SMBus applications. It is designed for a wide voltage range of 1.65 V to 5.5 V with interrupt and default pull-up resistors on GPIOs. Nexperia GPIO expanders provide an elegant solution when additional IOs are needed while keeping the interconnections to a minimum, for example, in ACPI power switches, sensors, push buttons, LEDs and fan control. The NCA9555-Q100 contains a set of 8 bit input, output, configuration and polarity inversion registers. At power up all IOs default to inputs. Each IO can be configured as either input or output by changing the corresponding bit in the configuration register. The data for each input or output is stored in the corresponding input or output register. The polarity inversion register can be programmed to invert the polarity of the input register. The NCA9555-Q100 has an open-drain interrupt output which is activated when any one of the GPIO changes from its corresponding input port register state. The power on reset sets the registers to default values and initializes the device state machine. The NCA9555-Q100 has three address pins A0, A1 and A2 which can be used to configure the I²C bus slave address of the device. It allows up-to eight devices to share the same I²C-bus/SMBus.

This product has been qualified to the Automotive Electronics Council (AEC) standard Q100 (Grade 1) and is suitable for use in automotive applications.

Features and benefits

  • Automotive product qualification in accordance with AEC-Q100 (Grade 1)

    • Specified from -40 °C to +125 °C

  • I²C-bus to parallel port expander

  • Operating power supply voltage range of 1.65 V to 5.5 V

  • Low standby current consumption:

    • 4.0 µA (maximum)

  • Schmitt-trigger action allows slow input transition and better switching noise immunity at the SCL and SDA inputs

    • Vhys = 0.10 × VCC (typical)

    • Noise filter on SCL and SDA inputs

  • 5 V tolerant I/Os

  • 16 I/O pins which power up configured in input state with weak pull-up resistor
  • Open-drain active LOW interrupt output (INT)

  • 400 kHz Fast-mode I²C-bus

  • Internal power-on reset

  • No glitch on power-up

  • Latched outputs with 25 mA drive maximum capability for directly driving LEDs

  • Latch-up performance exceeds 100 mA per JESD78, Class II

  • ESD protection:

    • HBM ANSI/ESDA/JEDEC JS-001 Class 2 exceeds 2000 V

    • CDM ANSI/ESDA/JEDEC JS-002 Class C3 exceeds 1000 V


Type number Product status VCC (V) Logic switching levels Power dissipation considerations Tamb (°C) Package name
NCA9555BY-Q100 Production 1.65 - 5.5 CMOS low -40~125 HWQFN24


Type number Orderable part number, (Ordering code (12NC)) Status Marking Package Package information Reflow-/Wave soldering Packing
NCA9555BY-Q100 NCA9555BY-Q100HP
Active NCA9555 SOT8041-1
SOT8041-1 SOT8041-1_128

Environmental information

Type number Orderable part number Chemical content RoHS RHF-indicator
NCA9555BY-Q100 NCA9555BY-Q100HP NCA9555BY-Q100 rohs rhf rhf
Quality and reliability disclaimer

Documentation (11)

File name Title Type Date
NCA9555_Q100 Low-voltage 16-bit I²C and SMBus I/O expander with interrupt output and configuration registers Data sheet 2023-04-24
AN90044 A study of I2C with examples Application note 2023-07-03
nca9555 NCA9555 IBIS model IBIS model 2023-01-09
Nexperia_document_leaflet_I2C_GPIO_expanders I2C GPIO Expanders 2023 Leaflet 2023-04-26
SOT8041-1 plastic thermal enhanced very very thin Quad Flat packages, no leads;24 terminals; 0.5 mm pitch; 4 x 4 x 0.75 mm body Package information 2024-04-23
SOT8041-1_128 QFN4x4 24L; Reel pack for SMD, 13"; Q2/T3 product orientation Packing information 2022-08-01
NCA9555BY-Q100_Nexperia_Product_Reliability NCA9555BY-Q100 Nexperia Product Reliability Quality document 2023-05-29
NCA95XX_Arduino_Sketches NCA95XX Arduino™ Sketch Examples Software 2023-03-12
NCA95XX_EVB_Software NCA95XX EVB GUI Software 2023-03-12
UM90016 NCA95xx GPIO expander EVB (Arduino™ shield compatible) User manual 2024-02-23
UM90017 NCA95XX Evaluation Board: Quick-Start Guide User manual 2023-01-18


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File name Title Type Date
nca9555 NCA9555 IBIS model IBIS model 2023-01-09

Ordering, pricing & availability

Type number Orderable part number Ordering code (12NC) Status Packing Packing Quantity Buy online
NCA9555BY-Q100 NCA9555BY-Q100HP 935691442128 Active SOT8041-1_128 3,000 Order product


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Orderable parts

Type number Orderable part number Ordering code (12NC) Package Buy from distributors
NCA9555BY-Q100 NCA9555BY-Q100HP 935691442128 SOT8041-1 Order product