Dallas, Tex.Texas Instruments Inc. has released three 4-bit bidirectional translating (level-shifting) I²C and SMBus multiplexers and switches. The PCA9544A, PCA9545A and PCA9546A support voltage level translation between 2.5-, 3.3- and 5-V buses required in mixed voltage I²C systems.
The PCA9544A, PCA9545A and PCA9546A are useful for a range of applications, including system monitoring in both telecom and computing. The PCA9544A, PCA9545A and PCA9546A are controlled through the I²C bus, which is a two-wire communication bus standard that continues to be adopted in many system applications, including computing and portable electronics.
Each upstream channel (SCL/SDA) fans out to four downstream channels where each individual SCn/SDn channel or combination of channels can be selected through the contents of the programmable control register. This type of internal architecture allows designers to isolate a section of the I ²C bus through I ²C software, which provides pin savings in the processor. The free pins on the processor can be used for other functions. The I²C switches and multiplexers can also be used to resolve I²C address conflicts. The devices also support standard- and fast-mode speeds.
Of the three devices, the PCA9545A has the highest feature set since all four channels can be selected at the same time. The device offers an interrupt output and reset input along with a low on-state resistance (Ron=10 ohms), improving signal degradation between the input and output channels.
All three devices are available now with free samples support. The PCA9544A, PCA9545A and PCA9546A are available in the industry standard 20-pin SSOP, TSSOP, SOIC, and TVSOP packages along with the space-saving QFN and BGA package options. Budgetary pricing for the PCA9544ADGVR and PCA9545ADGVR (TVSOP) is set at $2.75 in quantities of 1,000. Budgetary pricing for the PCA9546ADGVR (TVSOP) is set at $1.74 in quantities of 1,000.
Texas Instruments Inc., 1-972-644-5580, www.ti.com.