SY89540UMY Micrel Inc, SY89540UMY Datasheet - Page 5

• Manufacturer Part Number: SY89540UMY
• Description: IC XPOINT SW 4X4 PREC 44-MLF
• Manufacturer: Micrel Inc
• Series: SY89r

Specifications of SY89540UMY

• Function: Crosspoint Switch
• Circuit: 1 x 4:4
• Voltage Supply Source: Single Supply
• Voltage - Supply, Single/dual (±): 2.375 V ~ 2.625 V
• Current - Supply: 200mA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 44-MLF®, QFN
• Number Of Arrays: 1
• Differential Data Transmission: Yes
• Power Supply Requirement: Single
• Mounting: Surface Mount
• Operating Temperature (max): 85C
• Operating Temperature (min): -40C
• Operating Temperature Classification: Industrial
• Cascading Capability: No
• Line Code: NRZ
• On-chip Buffers: No
• On-chip Decoder: No
• On-chip Latch Circuit: No
• On-chip Mux/demux: No
• Programmable: No
• Dual Supply Voltage (typ): Not RequiredV
• Dual Supply Voltage (max): Not RequiredV
• Dual Supply Voltage (min): Not RequiredV
• Input Level: CML/LVDS/LVPECL
• Output Level: LVDS
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 576-3241

Functional Description
Buffer Mode
SY89540 can be used as a 1:4 fanout buffer. This is
the default mode with LOAD and CONFIG being HIGH
when the device is first powered up. The SIN0 and
SIN1 inputs select the input signal that will be buffered.
Regardless of the output switch selection, the input
signal will be buffered to all four outputs.
Crosspoint Mode
SY89540 can be programmed to take differential input
signals from any input and buffer the signals to one or
more outputs. Prior to configuring SIN and SOUT,
LOAD and CONFIG must be LOW. To program the
desired
sequence:
December 2007
1) Select the desired input with the SIN0 and
2) Pulse the LOAD with a positive pulse to load
3) Pulse the CONFIG pin with a positive pulse to
4) This
SIN1 inputs and the output with the SOUT0
and SOUT1.
SIN and SOUT.
latched the I/O configuration.
independent
outputs. Below is the truth table to create a 4:4
buffer where IN0 -> Q3, IN1 -> Q2, IN2 -> Q1,
and IN3 -> Q0:
Input
I/O
IN0
IN1
IN2
IN3
method
combination,
SIN1
paths
0
0
1
1
can
between
be
follow
SIN0
used
0
1
0
1
the
Table 1. 4:4 Buffer Truth Table
inputs
to
following
SOUT1
create
1
1
0
0
and
5
The SY89540 can be switched from crosspoint mode
to a 1:4 fanout buffer simply by providing a LOW-to-
HIGH pulse to the LOAD and CONFIG pins. The input
configuration (SIN0:1) will select the desired input
signal while the output switch will buffer the selected
input signal. To get the same desired input to all four
outputs (1:4), LOAD and CONFIG must be repeated
four times to cover all outputs (i.e., SOUT0:1 must go
through all four output combinations, repeated by
LOAD and CONFIG).
SOUT0
1
0
1
0
Load
0
0
0
0
[e-mail]
Config.
0
0
0
0
or [phone]
M9999-120607-C
Output
Q3
Q2
Q1
Q0