PCA9616PW: 3-channel multipoint Fast-mode Plus differential I²C-bus buffer with hot-swap logic

The PCA9616 is a Fast-mode Plus (Fm+) SMBus/I²C-bus buffer that extends the normal single-ended SMBus/I²C-bus through electrically noisy environments using a differential SMBus/I²C-bus (dI²C) physical layer, which is transparent to the SMBus/I²C-bus protocol layer. It consists of three single-ended to differential driver channels for the SCL (serial clock), SDA (serial data), and a third channel useful for INT or other signaling.

Remark: If the third channel is not used, the INT pin (pin 7 of the TSSOP16 package) should not be left disconnected or ‘floating’ (it may generate incorrect bus signals due to system noise entering this high-impedance node). Tie it to VSS.

The use of differential transmission lines between identical dI²C bus buffers removes electrical noise and common-mode offsets that are present when signal lines must pass between different voltage domains, are bundled with hostile signals, or run adjacent to electrical noise sources, such as high energy power supplies and electric motors.

The SMBus/I²C-bus was conceived as a simple slow speed digital link for short runs, typically on a single PCB or between adjacent PCBs with a common ground connection. Applications that extend the bus length or run long cables require careful design to preserve noise margin and reject interference.

The dI²C-bus buffers were designed to solve these problems and are ideally suited for rugged high noise environments and/or longer cable applications, allow multiple slaves, and operate at bus speeds up to 1 MHz clock rate. Cables can be extended to at least three meters (3 m), or longer cable runs at lower clock speeds. The dI²C-bus buffers are compatible with existing SMBus/I²C-bus devices and can drive Standard, Fast-mode, and Fast-mode Plus devices on the single-ended side.

Signal direction is automatic, and requires no external control. To prevent bus latch up, the standard SMBus/I²C-bus side of the bus buffer, the PCA9616 employs static offset, care should be taken when connecting these to other SMBus/I²C-bus buffers that may not operate with static offset.

This device is a bridge between the normal 2-wire single-ended wired-OR SMBus/I²C-bus and the 4-wire dI²C-bus.

Additional circuitry allows the PCA9616 to be used for ‘hot swap’ applications, where systems are always on, but require insertion or removal of modules or cards without disruption to existing signals.

The PCA9616 has two supply voltages, VDD(A) and VDD(B). VDD(A), the card side supply, only serves as a reference and ranges from 0.8 V to 5.5 V. VDD(B), the line side supply, serves as the majority supply for circuitry and ranges from 3.0 V to 5.5 V.

Outline 3d SOT403-1
Data Sheets (1)
Name/DescriptionModified Date
3-channel multipoint Fast-mode Plus differential I2C-bus buffer with hot-swap logic (REV 2.0) PDF (941.0 kB) PCA961610 Mar 2014
Users Guides (1)
Name/DescriptionModified Date
User manual for dI2C demo board (REV 1.0) PDF (813.0 kB) UM1085617 Jul 2015
Package Information (1)
Name/DescriptionModified Date
plastic thin shrink small outline package; 16 leads; body width 4.4 mm (REV 1.0) PDF (300.0 kB) SOT403-108 Feb 2016
Packing (1)
Name/DescriptionModified Date
TSSOP16; Reel pack; SMD, 13" Q1/T1 Standard product orientation Orderable part number ending ,118 or... (REV 1.0) PDF (218.0 kB) SOT403-1_11808 Apr 2013
Supporting Information (1)
Name/DescriptionModified Date
Footprint for wave soldering (REV 1.0) PDF (16.0 kB) SSOP-TSSOP-VSO-WAVE08 Oct 2009
Ordering Information
ProductStatusPackage version
PCA9616PWActiveSOT403-1
Package Information
Product IDPackage DescriptionOutline VersionReflow/Wave SolderingPackingProduct StatusPart NumberOrdering code(12NC)MarkingChemical ContentRoHS / Pb Free / RHFLeadFree Conversion DateEFRIFR(FIT)MTBF(hour)MSLMSL LF
PCA9616PWSOT403-1SSOP-TSSOP-VSO-WAVEReel 13" Q1/T1ActivePCA9616PW,118 (9352 985 46118)Standard MarkingPCA9616PWAlways Pb-free0.04.02.5E811
3-channel multipoint Fast-mode Plus differential I2C-bus buffer with hot-swap logic pca9616pw
User manual for dI2C demo board pca9616pw
SOT403-1 LPC812M101JDH16
SSOP-TSSOP-VSO-WAVE LPC1114FDH28
Reel 13" Q1/T1 LPC812M101JDH16
PCA9633