Micrel, Inc.

SY58627L

Janaury 2006

5

M9999-012606-A

Pin Number

Pin Name

Pin Function

13, 14

RXLBQ,

/RXLBQ

Receiver loopback CML compatible output pair. When the SY58627L is in local

Loopback mode (LBSEL = 1), RXLBQ output is directed from TXLBIN (no

equalization). When the SY58627L is in normal mode (LBSEL = LOW) and the

RXLBQ output is not required, disable the RXLBQ output (/RXLBEN = HIGH) to

swing into a 50Ω load (100Ω across the pair). The RXLBQ output pair includes 50Ω

internal source termination resistors.

21, 19

RXQ,

/RXQ

Receiver differential CML compatible output pair: This CML-compatible output pair is

swing into a 50Ω load (100Ω across the pair). The RXQ output pair includes 50Ω

internal source termination resistors. When the SY58627L is in Loopback mode

(LBSEL = HIGH), then the RXQ output signal is directed from the unequalized

TXLBIN input.

26

LOS

Please contact factory Applications Engineers.

20

VTTOUT

Output termination center-tap: Each side of the RXQ differential output pair

terminates to the VTTOUT pin through 50Ω. The VTTOUT pin provides a center-tap

to the output termination network for maximum interface flexibility, and DC-offset

capability. Please refer to the “CML Output Interface Applications” section for more

details.

28

29

30

EQ2( MSB)

EQ1

EQ0

TTL/CMOS (or VTH controlled) compatible, 3-bit control interface. There are four

levels of equalization, as shown in the “Equalization Select Truth Table.” When the

MSB is logic HIGH, the RXQ output pair will not include any equalization.

000 = lowest equalization setting

001 = medium equalization setting

010 = medium-high equalization setting

011 = highest equalization setting

1XX = equalization bypass

1, 8, 9, 16, 17,

24, 25

VCC

Positive Power Supply: Connect to +3.3V power supply. Bypass with 0.1µF//0.01µF

low ESR capacitors as close to VCC pins as possible.

2, 5, 18, 22, 31,

32

VEE,

Exposed Pad

Ground: Ground pins and exposed pad must be connected to the same ground

plane.

Equalization Select Truth Table

Disable EQ

(MSB = EQ2)

Equalization

Select (EQ1)

Equalization

Select (EQ0)

Typical FR4 Length

Equalization

0

0

0

9”

Low

0

0

1

18”

Medium Low

0

1

0

24”

Medium High

0

1

1

36”

High

1

X

X

NA

Disabled