PCA9646D: Buffered 4-channel 2-wire bus switch
The PCA9646 is a monolithic CMOS integrated circuit for 2-wire bus buffering and switching in applications including I²C-bus, SMBus, PMBus, and other systems based on similar principles.
Each of the four outputs may be independently enabled in any combination as determined by the contents of the programmable control register. Each I/O is impedance isolated from all others, thus allowing a total of five branches of 2-wire bus with the maximum specified load (e.g., 5 × 400 pF for Fm+ I²C-bus at 1 MHz, or 5 × 4 nF at lower frequencies) (Ref. 1). More than one PCA9646 may be used in series, providing a substantial fan-out capability.
The PCA9646 includes a unidirectional buffer for the clock signal, and a bidirectional buffer for the data signal. The direction of the clock signal may also be set by the contents of the programmable control register. Clock stretching and timing must always be under control of the master device.
The PCA9646 has excellent application to 2-wire bus address expansion and increasing of maximum load capacitance. Very large LED displays are a perfect example.
PCA9646D: Product Block Diagram
sot109-1_3d
Data Sheets (1)
| Name/Description | Modified Date |
|---|---|
| Buffered 4-channel 2-wire bus switch (REV 2.0) PDF (162.0 kB) PCA9646 | 17 Jun 2015 |
Application Notes (3)
| Name/Description | Modified Date |
|---|---|
| Very large I2C-bus systems and long buses (REV 1.0) PDF (216.0 kB) AN11084 | 26 Oct 2011 |
| Level shifting techniques in I2C-bus design (REV 1.0) PDF (52.0 kB) AN10441 | 20 Jun 2007 |
| PCA954X FAMILY OF I²C / SMBus MULTIPLEXERS and SWITCHES (REV 2.0) PDF (807.0 kB) AN262 | 01 Oct 2004 |
Users Guides (3)
| Name/Description | Modified Date |
|---|---|
| I2C-bus specification and user manual (REV 6.0) PDF (1.4 MB) UM10204 | 28 Apr 2014 |
| I2C-bus specification and user manual (REV 5.0) PDF (1.6 MB) UM10204_JA | 03 Apr 2013 |
| I2C Demonstration Board 2005-1 Quick Start Guide (REV 1.0) PDF (261.0 kB) UM10206 | 13 Jun 2006 |
Brochures (2)
| Name/Description | Modified Date |
|---|---|
| NXP® I2C-bus solutions 2014: Smart, simple solutions for the 12 most common design concerns (REV 1.0) PDF (3.5 MB) 75017540 | 01 Aug 2014 |
| Add design fl exibility with multi-channel I2C/SMBus muxes and switches; NXP® 2-, 4-, and 8-channel... (REV 1.0) PDF (641.0 kB) 75016529 | 01 Jul 2008 |
Package Information (1)
| Name/Description | Modified Date |
|---|---|
| plastic small outline package; 16 leads; body width 3.9 mm (REV 1.0) PDF (192.0 kB) SOT109-1 | 08 Feb 2016 |
Packing (1)
| Name/Description | Modified Date |
|---|---|
| SO16; Reel pack; SMD, 13" Q1/T1 Standard product orientation Orderable part number ending ,118 or J Ordering... (REV 4.0) PDF (210.0 kB) SOT109-1_118 | 24 Apr 2013 |
Supporting Information (2)
| Name/Description | Modified Date |
|---|---|
| Footprint for reflow soldering (REV 1.0) PDF (9.0 kB) SO-SOJ-REFLOW | 08 Oct 2009 |
| Footprint for wave soldering (REV 1.0) PDF (8.0 kB) SO-SOJ-WAVE | 08 Oct 2009 |
IBIS Model
- PCA9646D IBIS Model (REV 1.0) ibs PCA9646D 2/14/2013
Ordering Information
| Product | Status | Package version | Application | Reset input pin | Function | Operating Temperature (Cel) | Number of bits | I2C-bus (kHz) | Operating voltage (VDC) | Operating voltage 2 (V) | Inputs | Outputs | Max Sink Current per bit (mA) | No of Addresses | Voltage Translation Range (V) | Max Sink Current, per package (mA) | Enable |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PCA9646D | End of Life | SOT109-1 | yes | -40~85 | 1000 | 2.7~5.5 | 1 | 4 | 8 |
Package Information
| Product ID | Package Description | Outline Version | Reflow/Wave Soldering | Packing | Product Status | Part NumberOrdering code(12NC) | Marking | Chemical Content | RoHS / Pb Free / RHF | LeadFree Conversion Date | MSL | MSL LF |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PCA9646D | | SOT109-1 | SO-SOJ-REFLOW
SO-SOJ-WAVE SO-SOJ-REFLOW SO-SOJ-WAVE | Reel 13" Q1/T1 | Discontinued | PCA9646D,118 (9352 927 09118) | PCA9646 | PCA9646D |    | Always Pb-free | 1 | 1 |
