1
SuperLite™
SY55858U
Micrel, Inc.
M9999-110705
hbwhelp@micrel.com or (408) 955-1690
DESCRIPTION
■Guaranteed AC parameters over temperature:
•f
MAX > 3.0GHz (3Gbps)
•t
r/ tf < 120ps
• Within-device skew < 25ps
■Non-blocking “switch architecture”
■Configurable as dual 2:1 mux, dual 1:2 fanout buffer,
1:4 fanout buffer, quad buffer, or dual 2 x 2 switch
■50Ω compatible outputs
■Unique input termination and VT pin for DC-coupled
and AC-coupled input signals–CML or PECL
■Fully differential inputs/outputs
■TTL/CMOS compatible control logic
■Wide supply voltage range: 2.3V to 3.6V
■Wide operating temperature range: –40°C to +85°C
■Available in 32-pin EPAD-TQFP package
The SY55858U is a low-voltage, high-speed dual 2 x 2
crosspoint switch with a flexible input that accepts CML
or PECL, and a 50Ω compatible differential CML (current-
mode logic) output. The non-blocking design allows any
input to connect to any output. Varying the state of the
select inputs allows SY55858U to be used in backup,
fault tolerant, protection and backplane distribution
applications.
The signal inputs (DA0–1 and DB0–1) have a unique
internal termination design that allows access to the
termination network through VT pins. This feature allows
the device to easily interface to other logic standards
such as AC-coupled or DC-coupled PECL/LVPECL
signals. For applications that require a single-channel
2 x 2 crosspoint, consider the SY55854.
FEATURES
2.5V/3.3V 3.0GHZ DUAL 2 x 2 CML
CROSSPOINT SWITCH
W/INTERNAL TERMINATION
SuperLite™
SY55858U
APPLICATIONS
■SONET/SDH optical transport
■Backplane redundancy
■Add-drop Multiplexers
Rev.: D Amendment: /0
Issue Date: November 2005
SuperLite is a trademark of Micrel, Inc.
SuperLite™
2
SuperLite™
SY55858U
Micrel, Inc.
M9999-110705
hbwhelp@micrel.com or (408) 955-1690
PACKAGE/ORDERING INFORMATION
Ordering Information(1)
Package Operating Package Lead
Part Number Type Range Marking Finish
SY55858UHI H32-1 Industrial SY55858UHI Sn-Pb
SY55858UHITR(2) H32-1 Industrial SY55858UHI Sn-Pb
SY55858UHG(3) H32-1 Industrial SY55858UHG with Pb-Free
Pb-Free bar-line indicator NiPdAu
SY55858UHGTR(2, 3) H32-1 Industrial SY55858UHG with Pb-Free
Pb-Free bar-line indicator NiPdAu
Notes:
1. Contact factory for die availability. Dice are guaranteed at TA = 25°C, DC Electricals only.
2. Tape and Reel.
3. Pb-Free package recommended for new designs.
32 31 30 29 28 27 26 25
910111213141516
1
2
3
4
5
6
7
8
24
23
22
21
20
19
18
17
DB1
VTB1
/DB1
SELB0
DB0
VTB0
/DB0
SELB1
GND
VCC
QA0
/QA0
VCC
QA1
/QA1
VCC
SELA0
/DA1
VTA1
DA1
SELA1
/DA0
VTA0
DA0
GND
VCC
/
QB0
QB0
VCC
/
QB1
QB1
VCC
Top View
EPAD-TQFP
H32-1
32-Pin EPAD-TQFP (H321)
SELA0 SELA1 QA0 QA1 Function
0 0 DA0 DA0 Fanout Buffer or Redundant Distribution
0 1 DA0 DA1 Dual Buffer or Crosspoint
1 0 DA1 DA0 Dual Buffer or Crosspoint
1 1 DA1 DA1 Fanout Buffer or Redundant Distribution
TRUTH TABLES
Table 1. Input to Output Connectivity Crosspoint A
SELB0 SELB1 QB0 QB1 Function
0 0 DB0 DB0 Fanout Buffer or Redundant Distribution
0 1 DB0 DB1 Dual Buffer or Crosspoint
1 0 DB1 DB0 Dual Buffer or Crosspoint
1 1 DB1 DB1 Fanout Buffer or Redundant Distribution
Table 2. Input to Output Connectivity Crosspoint B
3
SuperLite™
SY55858U
Micrel, Inc.
M9999-110705
hbwhelp@micrel.com or (408) 955-1690
PIN DESCRIPTION
Pin Number Pin Name Pin Function
1 DB1 Channel B1 posititve signal input.
2 VTB1 Channel B1 termination center-tap. For CML inputs, leave this pin floating.
Otherwise, see Figures 5a–5d in “Input Interface Application” section.
3 /DB1 Channel B1 negative signal input.
4 SELB0 Channel B0 output select. TTL/CMOS input.
5 DB0 Channel B0 positive signal input.
6 VTB0 Channel B0 termination center-tap. For CML inputs, leave this pin floating.
Otherwise, see Figures 5a–5d in “Input Interface Application” section.
7 /DB0 Channel B0 negative signal input.
8 SELB1 Channel B1 output select. TTL/CMOS input.
9, 24 GND Supply Ground.
10, 13, 16, 17, 20, 23 VCC Positive supply normally connect to 2.5V, 3.3V, or 5V nominal supply, and
bypass each pin with 0.1µF//0.01µF low ESR capacitors.
11 /QB0 Channel B0 negative signal output. 50Ω CML.
12 QB0 Channel B0 positive signal output. 50Ω CML.
14 /QB1 Channel B1 negative signal output. 50Ω CML.
15 QB1 Channel B1 positive signal output. 50Ω CML.
18 /QA1 Channel A1 negative signal output. 50Ω CML.
19 QA1 Channel A1 positive signal output. 50Ω CML.
21 /QA0 Channel A0 negative signal output. 50Ω CML.
22 QA0 Channel A0 positive signal output. 50Ω CML.
25 DA0 Channel A0 positive signal input.
26 VTA0 Channel A0 termination center-tap. For CML inputs, leave this pin floating.
Otherwise, see Figures 5a–5d in “Input Interface Application” section.
27 /DA0 Channel A0 negative signal input.
28 SELA1 Channel A1 output select. TTL/CMOS input.
29 DA1 Channel A1 positive signal input.
30 VTA1 Channel A1 termination center-tap. For CML inputs, leave this pin floating.
Otherwise, see Figures 5a–5d in “Input Interface Application” section.
31 /DA1 Channel A1 negative signal input.
32 SELA0 Channel A1 output select. TTL/CMOS input.
4
SuperLite™
SY55858U
Micrel, Inc.
M9999-110705
hbwhelp@micrel.com or (408) 955-1690
FUNCTIONAL BLOCK DIAGRAM
A0
0
1
0
1
A1
DA0
/DA0 VTA0 50Ω
50Ω
DA1
/DA1 VTA1 50Ω
50Ω
CML
CML
SELA0
SELA1
QA0
/QA0
QA1
/QA1
B0
0
1
0
1
B1
DB0
/DB0 VTB0 50Ω
50Ω
DB1
/DB1 VTB1 50Ω
50Ω
CML
CML
SELB0
SELB1
QB0
/QB0
QB1
/QB1
INPUT AND OUTPUT STAGE
50Ω
SY55858U
VCC
1.2mA
50Ω
D0
VT*
/D0
1.2mA
Figure 1. Input Stage
50Ω50Ω
SY55858U
v
cc
Q
16mA
/Q
Figure 2. Output Stage
Note 1. See “Input Interface Applications” section for proper input
connection.
5
SuperLite™
SY55858U
Micrel
Symbol Parameter Min. Typ. Max. Unit Condition
VCC Power Supply Voltage 2.3 —3.6 V
ICC Power Supply Current —150 190 mA No load, over temp.
DC ELECTRICAL CHARACTERISTICS
Symbol Parameter Min. Typ. Max. Unit Condition
VIH Input HIGH Voltage 2.0 ——V
VIL Input LOW Voltage ——0.8 V
IIH Input HIGH Current ——+20 µAV
IN = 2.7V, VCC = Max.
——+100 µAV
IN = VCC, VCC = Max.
IIL Input LOW Current –300 ——µAV
IN = 0.5V, VCC = Max.
Note 2. Specifications are guaranteed after thermal equilibrium has been establised.
TTL CONTROL ELECTRICAL CHARACTERISTICS
VCC = 2.3V to 3.6V; GND = 0V; TA = –40°C to +85°C(2)
Symbol Rating Value Unit
VCC Power Supply Voltage –0.5 to +6.0 V
VIN Input Voltage –0.5 to VCC +0.5 V
VOUT CML Output Voltage VCC –1.0 to VCC +0.5 V
TAOperating Temperature Range –40 to +85 °C
TLEAD Lead Temperature (soldering, 20sec.) 260 °C
Tstore Storage Temperature Range –65 to +150 °C
θJA Package Thermal Resistance –Still-Air (multi-layer PCB) 28 °C/W
(Junction-to-Ambient) –500lfpm (multi-layer PCB) 20 °C/W
θJC Package Thermal Resistance 4 °C/W
(Junction-to-Case)
Note 1. Permanent device damage may occur if absolute maximum ratings are exceeded. This is a stress rating only and functional operation is not
implied at conditions other than those detailed in the operational sections of this data sheet. Exposure to absolute maximum ratlng conditions
for extended periods may affect device reliability.
ABSOLUTE MAXIMUM RATINGS(1)
6
SuperLite™
SY55858U
Micrel, Inc.
M9999-110705
hbwhelp@micrel.com or (408) 955-1690
Symbol Parameter Min. Typ. Max. Unit Condition
fMAX Maximum Frequency
NRZ Data Rate 3.0 ——Gbps
Clock Frequency(6) 3.0 ——GHz
tPLH Differential Propagation Delay 220 350 450 ps
tPHL D-to-Q
tSWITCH Select-to-Valid Output(7) —0.50 1.0 ns
tSKEW Within-Device Skew(8) —12 25 ps
Within-Device Skew(9) —25 50 ps
Part-to-Part Skew (Diff.) —100 —
RJRandom Jitter —25ps
RMS
DJDeterministic Jitter —520ps
PP
tr, tfCML Output Rise/Fall Times —80 120 ps
(20% to 80%)
AC ELECTRICAL CHARACTERISTICS
VCC = 2.3V to 3.6V; GND = 0V; TA = –40°C to +85°C(5)
Note 5. Tested using environment of Figure 3, 50Ω equivalent load. AC parameters are guaranteed by design and characterization.
Note 6. fMAX clock is defined as the maximum toggle rate the device can operate while still achieving a 250mV minimum CML output swing, 50Ω
equivalent load.
Note 7. Input TTL/CMOS edge rate of <1.5ns.
Note 8. Worst-case difference between QA0 and QA1 from either DA0 or DA1 (or between QB0 and QB1 from either DB0 or DB1 respectively), when
both outputs come from the same input.
Note 9. Worst-case difference between QA and QB outputs, when DA or DB inputs are shorted.
Symbol Parameter Min. Typ. Max. Unit Condition
VID Differential Input Voltage 100 ——mV
RIN Differential Input Resistance
D-to-/D 90 100 110 Ω
VIH Input HIGH Voltage 1.6 —VCC V
VIL Input LOW Voltage 1.5 —VCC – 0.1 V
VOH Output HIGH Voltage VCC – 0.040 VCC – 0.010 VCC V No Load
VOL Output LOW Voltage VCC – 1.00 VCC – 0.800 VCC – 0.650 V No Load
VOUT(SWING) Output Voltage Swing(4) 0.650 0.800 1.00 V No Load
—0.400 —50Ω Environment
ROUT Output Source Impedance 40 50 60 Ω
Note 3. Device is guaranteed to meet the DC specifications, shown in the table above, after thermal equilibrium has been established. The device is
tested in a socket such that traverse airflow ≥500lfpm is maintained.
Note 4. VOUT(SWING) is defined as the swing on one output of a differential pair, that is |VOH – VOL| on one pin. The swing for common mode immunity
purposes is 2 ×VOUT(SWING). Actual voltage levels and differential swing will depend on customer termination scheme. Typically, a 400mV
swing is available in the 50Ω environment. Refer to the “CML Output Termination Application” section, Figures 3 and 4, for more details.
CML DC ELECTRICAL CHARACTERISTICS
VCC = 2.3V to 3.6V; GND = 0V; TA = –40°C to +85°C(3)
7
SuperLite™
SY55858U
Micrel, Inc.
M9999-110705
hbwhelp@micrel.com or (408) 955-1690
INPUT INTERFACE APPLICATIONS
CML D
/D
VTNC
SY55858
V
CC
V
CC
Figure 5a. CML-to-CML
(DC-Coupled) Input Interface
CML D
/D
VT
V
CC
V
CC
V
CC
– 1.3V
SY55858
Figure 5b. CML-to-CML
(AC-Coupled) Input Interface
PECL D
/D
VT
V
CC
V
CC
V
CC
– 2.0V
SY55858
Figure 5c. PECL-to-CML
(DC-Coupled) Input Interface
PECL D
/D
VT
220Ω220Ω
VCC VCC
VCC – 1.3V
SY55858
Figure 5d. PECL-to-CML
(AC-Coupled) Input Interface
CML OUTPUT TERMINATION APPLICATION
50Ω50Ω
SY55858U
vcc
100Ω
50Ω
50Ω
16mA
Figure 3. 50Ω Output Termination
All CML inputs accept a CML output from any other
member of this family. All CML outputs are source terminated
Q
OUT
/Q
OUT
800mV
(Q
OUT
—
/Q
OU
T
Differential
Q
OUT
/Q
OUT
400mV
(Single-Ended)
+
Figure 4. Output Levels
50Ω differential drivers as shown in Figure 3.
8
SuperLite™
SY55858U
Micrel, Inc.
M9999-110705
hbwhelp@micrel.com or (408) 955-1690
32 -PIN EPAD-TQFP (DIE UP) (H32-1)
Rev. 01
MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA
TEL + 1 (408) 944-0800 FAX + 1 (408) 474-1000 WEB http://www.micrel.com
The information furnished by Micrel in this datasheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its use.
Micrel reserves the right to change circuitry and specifications at any time without notification to the customer.
Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can
reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into
the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchaser’s
use or sale of Micrel Products for use in life support appliances, devices or systems is at Purchaser’s own risk and Purchaser agrees to fully indemnify
Micrel for any damages resulting from such use or sale.
© 2005 Micrel, Incorporated.
