MIC2550

Micrel

MIC2550

2

October 4, 1999

Pin Description

Pin Number

Pin Name

Pin Function

1

VIF

System Interface Supply Voltage (Input): Determines logic voltage levels for

system interface signaling to logic controller.

2

SPD

Speed (Input): Edge rate control. Logic high selects full-speed edge rates.

Logic low selects low-speed edge rates.

3

RCV

Receive Data (Output): System interface receive data interface to logic

controller.

4

VP

Plus (Input/Output): System interface signal to logic controller. If OE# is

logic 1, VP is a receiver output (+); If OE# is logic 0, VP is a driver input (+).

5

VM

Minus (Input/Output): System interface signal to logic controller. If OE# is

logic 1, VM is a receiver output (–); If OE# is logic 0, VM is a driver input (–).

6, 13

NC

not internally connected

7

GND

Ground: Power supply return and signal reference.

8

SUS

Suspend (Input): Logic high turns off internal circuits to reduce supply

current.

9

OE#

Output Enable (Input): Active-low system interface input signal from from

logic controller. Logic low causes transceiver to transmit data onto the bus.

Logic high causes the transceiver to receive data from the bus.

10

D–

USB Differential Data Line – (Input/Output)

11

D+

USB Differential Data Line + (Input/Output)

12

VTRM

Termination Supply (Output): 3.3V speed termination resistor supply output.

14

VBUS

USB Supply Voltage (Input): Transceiver supply.

Pin Configuration

2

SPD

3

RCV

4

VP

5

VM

6

NC

7

GND

1

VIF

VBUS

14

NC

13

VTRM

12

D+

11

D–

10

OE#

9

8

SUS

14-Pin TSSOP (TM)