Single Chip Solution
The PACUSB-U1/U2/U3 device terminates the 2 data lines for the USB port and is a single chip solution for USB upstream applications. There are three series resistor (R1) values available to engineers to match it and the USB driver's resistance with the USB cable's impedance. The three R1 values that CAMD offers are 15 ohms, 33 ohms, and 22 ohms for PACUSB-U1, PACUSB-U2, and PACUSB-U3 respectively. California Micro Devices' solution is silicon-based and its quality and reliability matches that of today's integrated circuits. With the integration of resistors, capacitors, and diodes on silicon, this device achieves termination, filtering and ESD protection of a USB port. The integration of all these components provide significant savings in cost and board space while enhancing the system's performance.