Micrel, Inc.
4-BIT SERIAL-to-PARALLEL
CONVERTER
SY10E445
SY100E445
SY10E445
SY100E445
FEATURES
s
On-chip clock
÷
4 and
÷
8
s
Extended 100E V
EE
range of –4.2V to –5.5V
s
2.5Gb/s data rate capability
s
Differential clock and serial inputs
s
V
BB
output for single-ended use
s
Asynchronous data synchronization
s
Mode select to expand to 8 bits
s
Internal 75k
Ω
input pull-down resistors
s
Fully compatible with Motorola MC10E/100E445
s
Available in 28-pin PLCC package
DESCRIPTION
The SY10/100E445 are integrated 4-bit serial-to-parallel
data converters. The devices are designed to operate for
NRZ data rates of up to 2.5Gb/s. The chip generates a
divide-by-4 and a divide-by-8 clock for both 4-bit conversion
and a two-chip 8-bit conversion function. The conversion
sequence was chosen to convert the first serial bit to Q
0
,
the second to Q
1
, etc.
Two selectable serial inputs provide a loopback capability
for testing purposes when the device is used in conjunction
with the E446 parallel-to-serial converter.
The start bit for conversion can be moved using the
SYNC input. A single pulse, applied asynchronously for at
least two input clock cycles, shifts the start bit for conversion
from Q
n
to Q
n-1
by one bit. For each additional shift required,
an additional pulse must be applied to the SYNC input.
Asserting the SYNC input will force the internal clock dividers
to "swallow" a clock pulse, effectively shifting a bit from the
Q
n
to the Q
n-1
output (see Timing Diagram B).
The MODE input is used to select the conversion mode
of the device. With the MODE input LOW (or open) the
device will function as a 4-bit converter. When the mode
input is driven HIGH, the data on the output will change on
every eighth clock cycle, thus allowing for an 8-bit conversion
scheme using two E445s. When cascaded in an 8-bit
conversion scheme, the devices will not operate at the
2.5Gb/s data rate of a single device. Refer to the applications
section of this data sheet for more information on cascading
the E445.
For lower data rate applications, a V
BB
reference voltage
is supplied for single-ended inputs. When operating at clock
rates above 500MHz, differential input signals are
recommended. For single-ended inputs, the V
BB
pin is tied
to the inverting differential input and bypassed via a 0.01µF
capacitor. The V
BB
provides the switching reference for the
input differential amplifier. The V
BB
can also be used to AC
couple an input signal.
PIN NAMES
Pin
SINA, SINA
SINB, SINB
SEL
SOUT, SOUT
Q0–Q3
CLK, CLK
CL/4, CL/4
CL/8, CL/8
MODE
SYNC
RESET
V
CCO
Function
Differential Serial Data Input A
Differential Serial Data Input B
Serial Input Select Pin
Differential Serial Data Output
Parallel Data Outputs
Differential Clock Inputs
Differential
÷4
Clock Output
Differential
÷8
Clock Output
Conversion Mode 4-bit/8-bit
Conversion Synchronizing Input
Input, Resets the Counters
V
CC
to Output
M9999-032206
hbwhelp@micrel.com or (408) 955-1690
Rev.: F
Amendment: /0
1
Issue Date: March 2006
Micrel, Inc.
SY10E445
SY100E445
PACKAGE/ORDERING INFORMATION
RESET
S
INA
S
INA
SYNC
MODE
NC
V
CCO
Ordering Information
(1)
Part Number
Package
Type
J28-1
J28-1
J28-1
J28-1
J28-1
J28-1
J28-1
J28-1
Operating
Range
Commercial
Commercial
Commercial
Commercial
Commercial
Commercial
Commercial
Commercial
Package
Marking
SY10E445JC
SY10E445JC
SY100E445JC
SY100E445JC
SY10E445JZ with
Pb-Free bar-line indicator
SY10E445JZ with
Pb-Free bar-line indicator
SY100E445JZ with
Pb-Free bar-line indicator
SY100E445JZ with
Pb-Free bar-line indicator
Lead
Finish
Sn-Pb
Sn-Pb
Sn-Pb
Sn-Pb
Matte-Sn
Matte-Sn
Matte-Sn
Matte-Sn
25 24 23 22 21 20 19
SY10E445JC
18
17
S
INB
S
INB
SEL
V
EE
CLK
CLK
V
BB
26
27
28
1
2
3
4
5
6
7
8
9
10 11
S
OUT
S
OUT
V
CC
Q
0
Q
1
V
CCO
Q
2
SY10E445JCTR
(2)
SY100E445JC
SY100E445JCTR
(2)
SY10E445JZ
(3)
SY10E445JZTR
(2, 3)
SY100E445JZ
(3)
SY100E445JZTR
(2, 3)
TOP VIEW
PLCC
J28-1
16
15
14
13
12
V
CCO
CL/4
28-Pin PLCC (J28-1)
Notes:
V
CCO
Q
3
CL/8
CL/8
CL/4
1. Contact factory for die availability. Dice are guaranteed at T
A
= 25°C, DC Electricals only.
2. Tape and Reel.
3. Pb-Free package is recommended for new designs.
M9999-032206
hbwhelp@micrel.com or (408) 955-1690
2
Micrel, Inc.
SY10E445
SY100E445
BLOCK DIAGRAM
SINB
SINB
SINA
SINA
SEL
D
Q
D
Q
0
1
D
D
Q
D
Q
Q
3
Q
2
D
Q
D
Q
Q
1
D
Q
D
Q
Q
0
SOUT
SOUT
CLK
CLK
÷4
R
0
÷2
R
MODE
RESET
SYNC
VBB
1
CL/8
CL/8
CL/4
CL/4
M9999-032206
hbwhelp@micrel.com or (408) 955-1690
3
Micrel, Inc.
SY10E445
SY100E445
TRUTH TABLES
LOGIC DIAGRAM
Mode
L
H
Conversion
4-Bit
8-Bit
SEL
H
L
Serial Input
A
B
DC CHARACTERISTICS
LOGIC DIAGRAM
V
EE
= V
EE
(Min.) to V
EE
(Max.); V
CC
= V
CCO
= GND
T
A
= 0
°
C
Symbol
I
IH
V
OH
Parameter
Input HIGH Current
Output HIGH Voltage
(S
OUT
only) 10E
(S
OUT
only) 100E
Output Reference Voltage
10E
100E
Power Supply Current
10E
100E
—
—
154
154
185
185
—
—
154
154
185
185
—
—
154
177
185
212
Min.
—
–1020
–1025
–1.38
–1.38
Typ.
—
—
—
—
—
Max.
150
T
A
= +25
°
C
Min.
—
Typ.
—
—
—
—
—
Max.
150
—
T
A
= +85
°
C
Min.
Typ.
—
—
—
—
—
Max.
150
–670
–830
V
–1.27 –1.35
–1.26 –1.38
–1.25 –1.31
–1.26 –1.38
–1.19
–1.26
mA
—
Unit
µA
V
–790 –980
–830 –1025
–760 –910
–830 –1025
1
1
Condition
—
V
BB
I
EE
Note:
1. The maximum VOH limit was relaxed from standard ECL due to the high frequency output design. All other outputs are specified with the standard 10E
and 100E VOH levels.
AC CHARACTERISTICS
LOGIC DIAGRAM
V
EE
= V
EE
(Min.) to V
EE
(Max.); V
CC
= V
CCO
= GND
T
A
= 0
°
C
Symbol
f
MAX
t
PD
Parameter
Max. Conversion Frequency
Propagation Delay to Output
CLK to Q
CLK to S
OUT
CLK to CL/4
CLK to CL/8
Set-up Time
SINA, SINB
SEL
Hold Time, SINA, SINB, SEL
Reset Recovery Time
Minimum Pulse Width
CLK, MR
Rise/Fall Times
20% to 80%
S
OUT
Other
Min.
2.0
2.5
1500
800
1100
1100
–100
0
450
500
400
Typ.
—
—
1800
975
1325
1325
–250
–200
300
300
—
Max.
—
—
2100
1150
1550
1550
—
—
—
—
—
2.0
2.5
1500
800
1100
1100
–100
0
450
500
400
T
A
= +25
°
C
Min.
Typ.
—
—
1800
975
1325
1325
–250
–200
300
300
—
Max.
—
—
2100
1150
1550
1550
—
—
—
—
—
2.0
2.5
1500
800
1100
1100
–100
0
450
500
400
T
A
= +85
°
C
Min.
Typ.
—
—
1800
975
1325
1325
–250
–200
300
300
—
Max.
—
—
2100
1150
1550
1550
ps
—
—
—
—
—
ps
ps
ps
ps
100
200
225
425
350
650
100
200
225
425
350
650
100
200
225
425
350
550
—
—
—
—
—
Unit
Gb/s
NRZ
ps
Condition
1
2
—
t
S
t
H
t
RR
t
PW
t
r
t
f
Notes:
1. Guaranteed for input clock amplitudes of 150mV to 800mV.
2. Guaranteed for input clock amplitudes of 150mV to 400mV.
M9999-032206
hbwhelp@micrel.com or (408) 955-1690
4
Micrel, Inc.
SY10E445
SY100E445
APPLICATIONS INFORMATION
LOGIC DIAGRAM
The SY10/100E are integrated 1:4 serial-to-parallel
converters. The chips are designed to work with the
E446 devices to provide both transmission and receiving
of a high-speed serial data path. The E445, under special
input conditions, can convert up to a 2.5Gb/s NRZ data
stream into 4-bit parallel data. The device also provides
a divide-by-four clock output to be used to synchronize
the parallel data with the rest of the system.
The E445 features multiplexed dual serial inputs to
provide test loop capability when used in conjunction
with the E446. Figure 1 illustrates the loop test
architecture. The architecture allows for the electrical
testing of the link without requiring actual transmission
over the serial data path medium. The SINA serial input
of the E445 has an extra buffer delay and, thus, should
be used as the loop back serial input.
SOUT
SOUT
To Serial
Medium
Clock
Clock
E445a
Serial Input
Data
SIN
SIN
SOUT
SOUT
SIN
SIN
Q
3
Q
2
Q
1
Q
0
E445b
Q
3
Q
2
Q
1
Q
0
Q
7
Q
6
Q
5
Q
4
Q
3
Q
2
Q
1
Q
0
Parallel Output Data
100ps
Clock
Tpd CLK
to SOUT
800ps
1050ps
Parallel
Data
Figure 2. Cascaded 1:8 Converter Architecture
Parallel
Data
SINA
SINA
SINB
SINB
From Serial
Medium
Figure 1. Loop Test Architecture
clock-to-serial-out would potentially cause a serial bit to
be swallowed (Figure 3). With a minimum delay of 800ps
on this output, the clock for the lower order E445 cannot
be delayed more than 800ps relative to the clock of the
first E445 without potentially missing a bit of information.
Because the set-up time on the serial input pin is
negative, coincident excursions on the data and clock
inputs of the E445 will result in correct operation.
Clock a
The E445 features a differential serial output and a
divide-by-8 clock output to facilitate the cascading of two
devices to build a 1:8 demultiplexer. Figure 2 illustrates
the architecture of a 1:8 demultiplexer using two E445s.
The timing diagram for this configuration can be found
on the following page. Notice the serial outputs (S
OUT
)
of the lower order converter feed the serial inputs of the
higher order device. This feedthrough of the serial inputs
bounds the upper end of the frequency of operation. The
clock-to-serial output propagation delay, plus the set-up
time of the serial input pins, must fit into a single clock
period for the cascade architecture to function properly.
Using the worst case values for these two parameters
from the data sheet, t
PD
CLK to S
OUT
= 1150ps or a
clock frequency of 950MHz.
The clock frequency is significantly lower than that of
a single converter. To increase this frequency, some
games can be played with the clock input of the higher
order E445. By delaying the clock feeding the second
E445 relative to the clock of the first E445, the frequency
of operation can be increased. The delay between the
two clocks can be increased until the minimum delay of
M9999-032206
hbwhelp@micrel.com or (408) 955-1690
Clock b
Tpd CLK
to SOUT
800ps
1050ps
Figure 3. Cascade Frequency Limitation
Perhaps the easiest way to delay the second clock
relative to the first is to take advantage of the differential
clock inputs of the E445. By connecting the clock for the
second E445 to the complimentary clock input pin, the
device will clock a half a clock period after the first E445
(Figure 4). Utilizing this simple technique will raise the
potential conversion frequency up to 1.5GHz. The divide-
by-eight clock of the second E445 should be used to
synchronize the parallel data to the rest of the system as
the parallel data of the two E445s will no longer be
synchronized. This skew problem between the outputs
can be worked around as the parallel information will be
static for eight more clock pulses.
5
模拟电子
