USBDF02W5

USBDFxxW5 EMI filter and line termination for USB downstream ports Applications EMI Filter and line termination for USB downstream ports on: Desktop computer SOT323-5L Notebooks Workstations Functional diagram USB Hubs Features Rt D+ Out D+ In Monolithic device with recommended line Ct Rd termination for USB downstream ports Integrated Rt series termination and Ct Gnd bypassing capacitors. Rd Ct Integrated ESD protection D- In D- Out Small package size Rt Description R R C t d t The USB specification requires USB downstream USBDF01W5 33 15 k 47 pF ports to be terminated with pull-down resistors USBDF02W5 15 15 k 47 pF from the D+ and D- lines to ground. On the implementation of USB systems, the radiated and Tolerance 10% 10% 20% conducted EMI should be kept within the required levels as stated by the FCC regulations. In Order codes addition to the requirements of termination and EMC compatibility, the computing devices are Part number Marking required to be tested for ESD susceptibility. USBDF01W5 UD1 The USBDFxxW5 provides the recommended line termination while implementing a low pass filter to USBDF02W5 UD2 limit EMI levels and providing ESD protection which exceeds IEC 61000-4-2 level 4 standard. Benefits The device is packaged in a SOT323-5L, which is a very small (50% smaller than the standard EMI / RFI noise suppression SOT23). Required line termination for USB downstream ports Complies with the following standards ESD protection exceeding IEC 61000-4-2, level 4 15 kV (air discharge) IEC61000-4-2 level 4 IPAD technology provides high flexibility in 8 kV (contact discharge) the design of high density boards MIL STD 883C, Method 3015-6 Tailored to meet USB 1.1 standard Class 3 C = 100 pF R = 1500 W TM: IPAD is a trademark of STMicroelectronics 3 positive strikes and 3 negative strikes (F = 1 Hz) September 2006 Rev 3 1/11 www.st.com 11Characteristics USBDFxxW5 1 Characteristics Table 1. Absolute maximum ratings (T = 25 C) amb Symbol Parameter Value Unit ESD discharge IEC 61000-4-2, contact discharge 15 V kV PP ESD discharge - MIL STD 883 - Method 3015-6 25 T Operating junction temperature range -40 to 150 C j T Storage temperature range - 55 to +150 C stg T Lead solder temperature (10 second duration) 260 C L P Power rating per resistor 100 mW r Table 2. Electrical characteristics (T = 25 C) amb Symbol Parameters Test conditions Min Typ Max Unit V Diode breakdown voltage I = 1 mA 6 V BR R V Diode forward voltage drop I = 50 mA 0.9 V F F 2 Application information Figure 1. USB Standard requirements +Vbus 1.5k Rt D+ D+ Rt Full-speed or Full-speed USB Ct Ct Low-speed USB Twisted pair shielded Transceiver Rt Rt Transceiver Zo = 90ohms D- D- Ct 15k 15k 5m max Ct Host or Hub 0 or Hub port Full-speed function FULL SPEED CONNECTION +Vbus 1.5k Rt Rt D+ D+ Full-speed or Low-speed USB Ct Ct Low-speed USB Untwisted unshielded Transceiver Rt Rt Transceiver 3m max D- D- 15k 15k Ct Ct Hub 0 or Host or Low-speed function Hub port LOW SPEED CONNECTION 2/11