PCA9535DB - 16-Bit I2C/SMBus GPIO Expander | Texas Instruments
Référence : PCA9535DB ✓ ActifPCA9535DB Présentation
An I/O expander is an interface IC that adds parallel digital input or output capability to a serial bus system. The PCA9535DB belongs to the I/O expander hierarchy within interface ICs, enabling a host microcontroller to control or monitor multiple lines while reducing the number of host GPIO pins required. Its I2C-compatible interface makes it suitable for systems using embedded processors, industrial controllers, communication equipment, and consumer electronics.
The PCA9535 offers 16 I/O pins, 2.3 V to 5.5 V operation, 400 kHz bus support, low standby-current consumption, and a dedicated interrupt output. Each port can be configured as input or output through the device registers, allowing mixed input/output designs on the same expander. The configuration registers also support device-level and port-level control, making the device useful for systems requiring distributed digital I/O.
Compared with a microcontroller dedicated to GPIO expansion, the PCA9535DB offloads repetitive parallel I/O handling to a low-power serial peripheral. Its 16-bit architecture reduces the number of external connections, while the interrupt line allows the host to respond to input changes without continuously polling every port. The I2C and SMBus interface also simplifies integration with widely adopted embedded buses.
Typical applications include industrial control panels, keypad and LED scanning, remote sensor interfaces, programmable logic controllers, communication modules, and consumer products requiring additional GPIO. The PCA9535DB is particularly useful when a design requires bidirectional digital lines, change notification, or bus-addressed peripheral control.
For PCB implementation, place the device close to the supported connector or controlled signal group and route I2C SDA and SCL away from noisy power paths. Confirm the device address configuration and account for pull-up requirements in the complete bus design. This page combines verified manufacturer and distributor information, package details, commercial guidance, practical design notes, and drop-in replacement considerations for engineers evaluating the PCA9535DB.
Alternatives de remplacement direct pour PCA9535DB — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Variantes de cette série
Modèles de la même série directement compatibles avec PCA9535DB (même facteur de forme et même empreinte) — différant par Interrupt Output, Device Type, Package, Interface, Packaging.
PCA9535DBR
✅ Remplacement directContactez-nous pour le prix
Voir la fiche technique →PCA9535CDB
✅ Remplacement direct ⚠️ Spécifications non vérifiées📋 Alternative de référence (hors catalogue)
PCA9555DB
✅ Remplacement directContactez-nous pour le prix
Voir la fiche technique →PCA9535DW
✅ Remplacement direct ⚠️ Spécifications non vérifiéesContactez-nous pour le prix
Voir la fiche technique →PCA9535DBG4
✅ Remplacement direct ⚠️ Spécifications non vérifiées📋 Alternative de référence (hors catalogue)
PCA9535DB Spécifications
| Device Type | Remote 16-bit I2C/SMBus low-power I/O expander |
| Number of I/O | 16 |
| Supply Voltage Range | 2.3 V to 5.5 V |
| I2C/SMBus Clock Frequency | 400 kHz |
| Interface | I2C/SMBus |
| Interrupt Output | Yes |
| Configuration Registers | Yes |
| I/O Direction Control | Programmable input/output |
| Standby Current Consumption | 1 uA maximum |
| Boîtier | 24-SSOP (0.209, 5.30 mm width) |
| Packaging | Tube |
Guide de configuration des broches du PCA9535DB 24-ssop (0.209, 5.30 mm width)
Configuration des broches du PCA9535DB (boîtier 24-ssop (0.209, 5.30 mm width)). La numérotation des broches, les fonctions et les schémas de connexion sont définis dans la fiche technique du fabricant. Consultez-la pour l'empreinte exacte et les directives de soudage.
Aucune donnée de brochage détaillée disponible pour PCA9535DB.
Consultez la fiche technique pour la configuration complète des broches.
Applications typiques
PCA9535DB convient pour 6 applications: Industrial Control Panels, LED and Keypad Scanning, Remote Sensor and Actuator Interface, Programmable Logic Controller I/O, Communication Equipment, Consumer and Embedded Products.
Industrial Control Panels
The PCA9535DB fits industrial control panels that need more digital lines than the host controller can expose directly. Its 16 I/O pins can drive status indicators, read pushbuttons, or operate relay-control inputs while the I2C/SMBus interface remains the central communication path. The 2.3 V to 5.5 V operating range supports common industrial logic levels, and the interrupt output lets the controller react to changed inputs instead of continuously polling. Because the verified data does not specify the temperature range, qualification status, or exact output-current limits, the final component selection must be checked against the enclosure environment and load requirements.
Recommandé
LED and Keypad Scanning
The PCA9535DB is suitable for LED and keypad scanning designs where a compact controller needs additional parallel outputs and inputs. Its 16 configurable I/O lines can be assigned across display, indicator, and switch functions, while the 400 kHz I2C/SMBus interface provides a practical shared-bus rate for embedded products. The interrupt output can identify a key or input change so the host can update the display more efficiently. The 24-SSOP package supports compact layouts, but external current limiting, LED drive limits, debouncing, and bus pull-up components must be selected from the final electrical design.
Recommandé
Remote Sensor and Actuator Interface
The PCA9535DB can bridge a serial bus host to remote digital sensors, actuators, and discrete interface signals. Sixteen configurable lines allow a design to mix input sensing and output control, and the interrupt output provides event notification for line-state changes. The 2.3 V to 5.5 V supply range and 400 kHz bus compatibility fit many embedded monitoring systems. The supplied sources do not verify the exact I/O drive current or input thresholds, so engineers must confirm signal-level compatibility, grounding, isolation requirements, and cable length before using the device with remote sensors.
Recommandé
Programmable Logic Controller I/O
The PCA9535DB is appropriate for programmable logic controller and embedded automation modules that need compact, bus-addressed parallel I/O. Its 16 I/O lines can expand discrete input channels and command outputs while retaining a straightforward I2C/SMBus connection to the controller. The interrupt output supports event-driven handling of input transitions, reducing unnecessary polling and helping maintain system responsiveness. Its 24-SSOP package and 2.3 V to 5.5 V operating range are attractive for compact control hardware, although production designs must confirm operating temperature, output loading, and isolation requirements against the verified manufacturer datasheet.
Recommandé
Communication Equipment
The PCA9535DB can add supervisory and control lines to communication equipment that uses an I2C/SMBus management interface. Sixteen configurable ports may monitor module-present, reset, fault, or enable signals and control local status indicators or peripheral enables. The 400 kHz bus rate supports normal embedded management traffic, while the interrupt output enables event-driven fault reporting. The low-power design and 2.3 V to 5.5 V range are useful in equipment with constrained power budgets. Exact logic thresholds, output-drive capability, and package temperature limits are not supplied in the verified snippets and must be confirmed before deployment.
Recommandé
Consumer and Embedded Products
The PCA9535DB is useful in consumer and embedded products that need miscellaneous digital I/O without dedicating many host-controller pins. It can control display-enable signals, read configuration switches, operate status LEDs, or monitor service inputs through a shared 400 kHz I2C/SMBus bus. The interrupt output allows efficient response to user or service events, and the 24-SSOP package supports compact board layouts. Designers should account for external pull-ups on SDA and SCL, define a unique device address, and verify the 2.3 V to 5.5 V supply compatibility with every attached peripheral. The verified data does not provide RoHS, REACH, or halogen-free declarations.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour PCA9535DB — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | PCA9535DBR | PCA9535CDB | PCA9555DB | PCA9535D | PCA9535DBG4 |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 24-SSOP | 24-SSOP - same package family | 24-SSOP - same package family | 24-SSOP - same package family | 24-SSOP - same package family | 24-SSOP - same package family |
| Device Type | 16-bit I2C/SMBus low-power I/O expander | PCA9535 family 16-bit I/O expander | PCA9535 family 16-bit I/O expander | 16-bit I/O expander | PCA9535 family 16-bit I/O expander | PCA9535 family 16-bit I/O expander |
| Number of I/O | 16 | 16 | 16 | 16 | 16 | 16 |
Principaux différenciateurs
- Low-power PCA9535 implementation (vs PCA9555DB)
- Directly documented same-family ordering candidate (vs PCA9535DBR)
- Event-driven host integration (vs PCA9535PW)
Notes de conception
Confirm the complete power architecture before layout. The verified device range is 2.3 V to 5.5 V, and the PCA9535 removes the internal I/O pull-up resistor found on the PCA9555. Do not assume that a PCA9555 design can be substituted without reviewing external pull-ups on the I/O lines. Provide local supply decoupling close to the device and keep the I2C pull-up network consistent with the system voltage and bus capacitance.
Keep the 24-SSOP footprint and pin numbering consistent with the exact orderable variant used for production. PCA9535PW is a TSSOP-related option in the cross-reference results and is not a guaranteed drop-in replacement for the PCA9535DB SSOP footprint. Before substituting any listed alternative, compare land patterns, pin-1 orientation, exposed connections, device address, and all register behavior against the current manufacturer datasheet.
Route SDA and SCL as short, continuous traces away from switching nodes and high-current output paths. The supported 400 kHz bus rate is reasonable for ordinary embedded systems, but margin depends on bus capacitance, pull-up strength, trace length, and the number of connected devices. Use the interrupt output for event-driven responses rather than polling continuously, and verify the polarity and masking behavior against the datasheet.
Informations de conformité
The supplied verified web data does not provide explicit RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals statements.
