I2C Bus Buffers Are Hot Swappable

Promising extensive system management and configuration control, the PCA951x family of hot-swappable I2C bus buffers is said to allow users to add more devices to a single bus than previously possible. The devices communicate between boards, allowing insertion and removal of boards within an active system without corrupting data. For multiple system management buses, they can act as a bus buffer with different voltages on each segment. The PCA9511 provides rise-time accelerators, a 1V pre-charge, and an idle-detect function. Otherwise similar, the PCA9510 eliminates the rise time accelerators for systems with multiple devices on a common bus or for light-load systems. The PCA9512 employs two VCC supplies and a hardware pin to disable the rise time accelerators. Two additional family members, the PCA9513/14, are variations of the PCA9511 with a higher rise-time accelerator turn-on threshold. Available in both 8-pin SO and TSSOPs, pricing starts at $1.60 each/10,000. ROYAL PHILIPS ELECTRONICS, San Jose, CA. (408) 617-4700.