Specifications
| Type | Description |
|---|---|
| Part Number | TCA9539 |
| Manufacturer | Texas Instruments |
| Product Type | Operational Amplifier |
| Category | Signal Chain |
| Package Case | TSSOP-24 7.80 mm x 4.40 mm; WQFN-24 4.00 mm x 4.00 mm; VQFN-24 4.00 mm x 4.00 mm |
| Interface | I2C and SMBus; two-line bidirectional bus |
| I/O Expansion Width | 16 bits; general-purpose parallel input/output expansion |
| Supply Voltage Range | 1.65-5.5 V; recommended operating conditions |
| Supported I2C Clock Frequency | 100 kHz, 400 kHz; Standard mode and Fast mode |
| Interrupt Output | Open-drain active-low INT; generated when an input port changes state; connect to VCC through pull-up resistor |
| Reset Input | Active-low RESET; hardware reset input; connect to VCC through pull-up resistor if unused |
| Address Pins | 2 hardware address pins; A0 and A1 selectable address inputs |
| Maximum Devices Per I2C Bus | 4 devices; using A0 and A1 hardware address pins |
| I/O Port Voltage Tolerance | 5 V tolerant; P-port I/O pins |
| Default I/O State | Inputs; at power-on, P00-P07 and P10-P17 are configured as inputs |
| Absolute Maximum Supply Voltage | -0.5 to 6 V; VCC absolute maximum ratings |
| Absolute Maximum Input Voltage | -0.5 to 6 V; VI absolute maximum ratings |
| Absolute Maximum Output Voltage | -0.5 to 6 V; VO absolute maximum ratings |
| Input Clamp Current | -20 mA; VI < 0 V |
| Output Clamp Current | -20 mA; VO < 0 V |
| Input-Output Clamp Current | ±20 mA; VO < 0 V or VO > VCC |
| Continuous Output Low Current | 50 mA; VO = 0 to VCC absolute maximum ratings |
| Continuous Output High Current | -50 mA; VO = 0 to VCC absolute maximum ratings |
| Continuous Current Through GND | -250 mA; absolute maximum ratings |
| Continuous Current Through VCC | 160 mA; absolute maximum ratings |
| Maximum Junction Temperature | 100 °C; absolute maximum ratings |
| Storage Temperature | -65 to 150 °C; absolute maximum ratings |
| ESD Rating HBM | ±2000 V; Human-body model, ANSI/ESDA/JEDEC JS-001 |
| ESD Rating CDM | ±1000 V; Charged-device model, JEDEC JESD22-C101 |
| High-Level Input Voltage | 0.7 x VCC to VCC; SCL, SDA inputs |
| High-Level Input Voltage | 0.7 x VCC to 5.5 V; A0, A1, RESET, P07-P00, P10-P17 inputs |
| Low-Level Input Voltage | -0.5 to 0.3 x VCC; SCL, SDA, A0, A1, RESET, P07-P00, P10-P17 inputs |
| High-Level Output Current | -10 mA; P07-P00, P17-P10 outputs |
| Low-Level Output Current | 25 mA max; P00-P07, P10-P17, Tj <= 65°C |
| Low-Level Output Current | 18 mA max; P00-P07, P10-P17, Tj <= 85°C |
| Low-Level Output Current | 11 mA max; P00-P07, P10-P17, Tj <= 100°C |
| Low-Level Output Current | 6 mA max; INT, SDA, Tj <= 85°C |
| Low-Level Output Current | 3.5 mA max; INT, SDA, Tj <= 100°C |
| Operating Free-Air Temperature | -40 to 85 °C; recommended operating conditions |
| Thermal Resistance Junction-to-Ambient | 108.8 °C/W; PW TSSOP-24 package |
| Thermal Resistance Junction-to-Ambient | 43.6 °C/W; RTW WQFN-24 package |
| Thermal Resistance Junction-to-Ambient | 48.4 °C/W; RGE VQFN-24 package |
| Input Diode Clamp Voltage | -1.2 V max; II = -18 mA, VCC = 1.65 V to 5.5 V |
| Power-On Reset Voltage Rising | 1.2 V typ, 1.5 V max; VCC rising, VCC = 1.65 V to 5.5 V |
| Power-On Reset Voltage Falling | 0.75 V typ, 1 V max; VCC falling, VCC = 1.65 V to 5.5 V |
| P-Port High-Level Output Voltage | 1.2 V min; IOH = -8 mA, VCC = 1.65 V |
| P-Port High-Level Output Voltage | 1.8 V min; IOH = -8 mA, VCC = 2.3 V |
| P-Port High-Level Output Voltage | 2.6 V min; IOH = -8 mA, VCC = 3 V |
| P-Port High-Level Output Voltage | 4.1 V min; IOH = -8 mA, VCC = 4.75 V |
| Datasheet Status | request_only |
Product Overview
The TCA9539 is a Texas Instruments 16-bit I2C I/O expander in the Signal_Chain category. It adds general-purpose parallel input/output through an I2C and SMBus two-line bidirectional interface, with support for 100 kHz Standard mode and 400 kHz Fast mode operation. Two address inputs, A0 and A1, select hardware addresses and allow up to four devices on the same I2C bus.
At power-on, ports P00-P07 and P10-P17 are configured as inputs. The P-port I/O pins are 5 V tolerant, while recommended operation spans a 1.65 V to 5.5 V supply range and -40 °C to 85 °C free-air temperature range. The device also provides an open-drain active-low INT output for input-port state changes and an active-low RESET input for hardware reset.
Package choices include TSSOP-24 at 7.80 mm x 4.40 mm, WQFN-24 at 4.00 mm x 4.00 mm, and VQFN-24 at 4.00 mm x 4.00 mm. Thermal resistance values are specified for each package, supporting package-level evaluation during board design.
Key Features
- 16-bit general-purpose parallel I/O expansion
- I2C and SMBus two-line bidirectional interface
- Supports 100 kHz and 400 kHz I2C clocks
- 1.65 V to 5.5 V recommended supply range
- Open-drain active-low interrupt output for input changes
- Active-low hardware reset input with pull-up option
- Two address pins support four bus devices
- P-port I/O pins are 5 V tolerant
- Ports default to inputs at power-on
- TSSOP-24, WQFN-24, and VQFN-24 package options
Typical Applications
- I2C-controlled GPIO expansion
- SMBus parallel I/O expansion
- Multi-device I2C bus designs
- Input change interrupt monitoring
- 5 V tolerant port interfacing
- Hardware reset controlled I/O systems
- Low-voltage embedded I/O expansion
Procurement Notes
When requesting a quote for TCA9539, buyers should confirm the manufacturer, package or case, required quantity, target date code, compliance documents, packing method, destination country and expected delivery schedule.
If alternatives are acceptable, buyers should share the approved vendor list, required electrical or optical limits, package constraints and qualification requirements. Any alternative part should be reviewed by the buyer's engineering team before production use.
For analog and signal-chain sourcing, supply voltage, bandwidth, accuracy, noise level, package, temperature grade, input/output configuration and qualification requirements should be verified before approval.
FAQ
What interface does the TCA9539 use for host communication?
The TCA9539 communicates through an I2C and SMBus two-line bidirectional bus. The extracted specifications list supported I2C clock frequencies of 100 kHz for Standard mode and 400 kHz for Fast mode.
How many I/O lines does the TCA9539 provide?
The device provides 16 bits of general-purpose parallel input/output expansion. At power-on, P00-P07 and P10-P17 are configured as inputs according to the extracted datasheet facts.
What supply voltage range is recommended for the TCA9539?
The recommended operating supply range is 1.65 V to 5.5 V. The absolute maximum supply voltage rating is listed separately as -0.5 V to 6 V and should not be treated as the recommended operating range.
How many TCA9539 devices can share one I2C bus?
Up to four devices can be used on one I2C bus by selecting addresses with the two hardware address pins, A0 and A1. These pins are listed as selectable address inputs.
Technical Review & Sourcing Note
Prepared by LDeepAI Component Sourcing Team. Reviewed for RFQ, documentation and alternative sourcing use. Last updated: June 30, 2026.
This page is based on manufacturer datasheet information and LDeepAI sourcing review. Specifications should be verified against the official manufacturer datasheet before final procurement or design approval. Final electrical, optical and reliability approval should be confirmed by the buyer's engineering team.