This is information on a product in full production.

August 2015

DocID7041 Rev 8

1/13

USBUF

EMI filter and line termination for USB upstream ports

Datasheet

Figure 1. Functional diagram

Features

• Monolithic device with recommended line

termination for USB upstream ports

• Integrated Rt series termination and Ct

bypassing capacitors.

• Integrated ESD protection

• Small package size

• Benefits

– EMI / RFI noise suppression

– Required line termination for USB

upstream ports

– ESD protection exceeding IEC 61000-4-2

level 4

– High flexibility in the design of high density

boards

– Tailored to meet USB 1.1 standard

• Complies with the following standards IEC

61000-4-2, level 4

– ± 15 kV (air discharge)

– ± 8 kV (contact discharge)

– MIL STD 883E, Method 3015-7

– Class 3 C = 100 pF; R = 1500

Ω

– 3 positive strikes and 3 negative strikes

(F = 1 Hz)

Application

EMI Filter and line termination for USB upstream

ports on:

• USB Hubs

• PC peripherals

Description

The USB specification requires upstream ports to

be terminated with pull-up resistors from the D+

and D- lines to Vbus. On the implementation of

USB systems, the radiated and conducted EMI

should be kept within the required levels as stated

by the FCC regulations. In addition to the

requirements of termination and EMC

compatibility, the computing devices are required

to be tested for ESD susceptibility.

The USBUF provides the recommended line

termination while implementing a low pass filter to

limit EMI levels and providing ESD protection

which exceeds IEC 61000-4-2 level 4 standard.

The device is packaged in a SOT323-6L which is

the smallest available lead frame package (50%

smaller than the standard SOT23).

SOT323-6L

3.3 V

Rp

Ct

Rt

Ct

Rt

D1

Grd

D2

D4

D3

3.3 V

Table 1. Device summary

Order codes

Marking

USBUF01W6

UU1

USBUF02W6

UU2

www.st.com