MAXIM MAX3950

19-1853; Rev 2; 12/02
+3.3V, 10.7Gbps 1:16 Deserializer
with LVDS Outputs
Features
♦ Supports Serial Data Rates Up to 10.7Gbps
♦ 10Gbps/10.7Gbps Serial to 622Mbps/667Mbps
Parallel Conversion
♦ Single +3.3V Supply
♦ 900mW Operating Power
♦ CML Serial Clock and Data Inputs
♦ LVDS Parallel Clock and Data Outputs
♦ -40°C to +85°C Operating Temperature
Applications
SONET/OC-192 SDH/STM-64 Transmission Systems
Add/Drop Multiplexers
Ordering Information
Broadband Digital Cross-Connects
PART
MAX3950EGK
TEMP RANGE
PIN-PACKAGE
-40°C to +85°C
68 QFN
Pin Configuration appears at the end of data sheet.
Typical Application Circuit
VCC
VCC
622Mbps
PD15+
VCC
SD+
IN+
OUT+
SDO-
SD-
PD15SDI+
IN+
PD0+
MAX3920*
TIA
MAX3940*
CDR
MAX3925*
AGC AMP
100Ω**
MAX3950
DESERIALIZER
OVERHEAD
PROCESSING
OUT+
SDO+
10Gbps
10Gbps
10Gbps
100Ω**
10Gbps
VCC
PD0-
INOUT-
IN-
OUT-
SDI-
SCLKO+
SCLK+
SCLKO-
SCLK-
PCLK+
100Ω**
PCLK-
*FUTURE PRODUCTS.
**REQUIRED ONLY IF OVERHEAD CIRCUIT DOES NOT INCLUDE INTERNAL INPUT TERMINATION.
THIS SYMBOL REPRESENTS A TRANSMISSION LINE OF CHARACTERISTIC IMPEDANCE Zo = 50Ω.
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
MAX3950
General Description
The MAX3950 deserializer is ideal for converting
10Gbps serial data to 16-bit-wide, 622Mbps parallel
data in SDH/SONET and DWDM applications.
Operating from a single +3.3V supply, this device
accepts CML serial clock and data inputs and delivers
low-voltage differential-signal (LVDS) clock and data
outputs for interfacing with high-speed digital circuitry.
The MAX3950 is available in the extended temperature
range (-40°C to +85°C) in a 68-pin QFN package. The
typical power dissipation is 900mW.
MAX3950
+3.3V, 10.7Gbps 1:16 Deserializer
with LVDS Outputs
ABSOLUTE MAXIMUM RATINGS
Positive Supply Voltage (VCC)...............................-0.5V to +5.0V
CML Input Voltage Level .................(VCC - 0.8V) to (VCC + 0.5V)
LVDS Output Voltage Level........................-0.5V to (VCC + 0.5V)
Continuous Power Dissipation (TA = +85°C)
68-Lead QFN (derate 43.5mW/°C above +85°C) ......2800mW
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-55°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
DC ELECTRICAL CHARACTERISTICS
(VCC = +3.0V to +3.6V, differential loads = 100Ω ±1%, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VCC =
+3.3V, TA = +25°C.)
PARAMETER
Supply Current
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
270
350
mA
400
1200
mVP-P
VCC 0.6
VCC +
0.3
V
57.5
Ω
1.375
V
ICC
CML INPUTS (SD±, SCLK±)
Differential Input Voltage Swing
VID
Single-Ended Input Voltage
Range
VIS
Input Termination to VCC
RIN
Figure 1
42.5
50
LVDS OUTPUT SPECIFICATION (PD[15.0] ±, PCLK±)
Output High Voltage
VOH
Output Low Voltage
VOL
Differential Output Voltage
Change in Magnitude of
Differential Output for
Complementary States
|VOD|
1.025
Figure 2
∆|VOD|
Offset Output Voltage
Change in Magnitude of
Output Offset Voltage for
Complementary States
1.15
∆|VOS|
Differential Output Impedance
Output Current
2
150
80
V
250
mV
25
mV
1.25
V
25
mV
120
Ω
Short together
12
Short to ground
24
_______________________________________________________________________________________
mA
+3.3V, 10.7Gbps 1:16 Deserializer
with LVDS Outputs
(VCC = +3.0V to +3.6V, differential loads = 100Ω ±1%, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VCC =
+3.3V, TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
Serial Input Data Rate
MAX
10
UNITS
Gbps
Serial Data Setup Time
tSU
25
ps
Serial Data Hold Time
tH
25
ps
Parallel Output Data Rate
622
Parallel Output Clock Frequency
622
Parallel Clock-to-Q Delay
tCLK-Q
(Note 2)
LVDS Output Rise/Fall Time
-200
Mbps
MHz
+200
ps
20% to 80%
300
ps
LVDS Differential Skew
tSKEW1
Any differential pair
65
ps
LVDS Channel-to-Channel Skew
tSKEW2
PD[15..0]±
200
100kHz ≤ f ≤ 5GHz
17
5GHz ≤ f ≤ 10GHz
14
10GHz ≤ f ≤ 15GHz
11
|S11|
Input Return Loss
ps
dB
Note 1: AC specifications are guaranteed by design and characterization.
Note 2: Relative to the falling edge of PCLK+. See Figure 3.
VCC + 0.3V
600mV
200mV
VCC
VCC - 0.3V
(a) AC-COUPLED CML INPUT
VCC
200mV
600mV
VCC - 0.6V
(b) DC-COUPLED CML INPUT
Figure 1. Input Amplitude
_______________________________________________________________________________________
3
MAX3950
AC ELECTRICAL CHARACTERISTICS
MAX3950
+3.3V, 10.7Gbps 1:16 Deserializer
with LVDS Outputs
PD+
RL = 100Ω
VOD
V
PD-
VPD-
VOH
IVODI
SINGLE-ENDED OUTPUT
VOS
VPD+
VOL
VPD+ - VPD-
DIFFERENTIAL OUTPUT
0
VODP-P = 2IVODI
Figure 2. Driver Output Levels
tCLK
SCLK+
t SU
tH
SD
PCLK+
tCLK-Q
PD
Figure 3. Timing Parameters
4
_______________________________________________________________________________________
+3.3V, 10.7Gbps 1:16 Deserializer
with LVDS Outputs
230
210
200
190
180
NOTE: MEASURED 20 TO 80%.
250
RISE/FALL TIME (ps)
220
MAX3950 toc02
240
MAX3950 toc03
300
MAX3950 toc01
250
PCLK+
200
PCLK-
DATA
150
CLOCK
100
PD
170
50
160
150
0
-20
0
20
40
60
80
-40
-20
0
20
40
60
200ps/div
80
AMBIENT TEMPERATURE (°C)
AMBIENT TEMPERATURE (°C)
OUTPUT EYE DIAGRAM
INPUT: 10.7Gbps, 213 - 1 +100 ZEROS PRBS
INPUT RETURN LOSS
MAX3950 toc04
0
NOTE: DATA IS FROM
SIMULATION AND INCLUDES
PACKAGE PARASITICS.
PCLK+
-5
PCLK-
MAX3950 toc05
-40
RETURN LOSS (dB)
SINGLE-ENDED LVDS OUTPUT (mVP-P)
OUTPUT EYE DIAGRAM
INPUT: 9.953Gbps, 213 - 1 +100 ZEROS PRBS
OUTPUT RISE/FALL TIME
vs. TEMPERATURE
LVDS OUTPUT AMPLITUDE
vs. TEMPERATURE
-10
-15
-20
PD
-25
-30
200ps/div
0
5
10
15
20
FREQUENCY (GHz)
Pin Description
PIN
NAME
FUNCTION
1, 2, 5, 13, 16, 17, 18,
26, 33–36, 42, 51, 52,
53, 60, 68
GND
Ground
6, 9, 12, 25, 31, 32,
37, 43, 50, 54, 55, 61
VCC
Positive Power Supply
7
SD+
Positive Data Input. 9.953Gbps serial data stream, CML.
8
SD-
Negative Data Input. 9.953Gbps serial data stream, CML.
10
SCLK+
Positive Serial Clock Input. 9.953GHz, CML.
11
SCLK-
Negative Serial Clock Input. 9.953GHz, CML.
14
PCLK-
Negative Parallel Clock Output, 622.08MHz, LVDS.
_______________________________________________________________________________________
5
MAX3950
Typical Operating Characteristics
(TA = +25°C, unless otherwise noted.)
+3.3V, 10.7Gbps 1:16 Deserializer
with LVDS Outputs
PIN
NAME
FUNCTION
15
PCLK+
Positive Parallel Clock Output, 622.08MHz, LVDS.
19, 21, 23, 27, 29, 38,
40, 44, 46, 48, 56, 58,
62, 64, 66, 3
PD0- to
PD15-
Negative Parallel Data Output, 622.08Mbps, LVDS.
20, 22, 24, 28, 30, 39,
41, 45, 47, 49, 57, 59,
63, 65, 67, 4
PD0+ to
PD15+
Positive Parallel Data Output, 622.08Mbps, LVDS.
EP
Exposed
Pad
Ground. This must be soldered to the circuit board ground for proper thermal and
electrical operation. See Layout Considerations.
CP
Corner
Pins
N.C. Not Connected. Ensure that the solder mask is located below them so that
unintentional connections do not occur.
4-BIT SHIFT
REGISTER
MAX3950
DATA
CLK
CML INPUT
D FLIP-FLOP
DELAY
4-BIT SHIFT
REGISTER
CML INPUT
DIVIDE BY 4
4-BIT SHIFT
REGISTER
4-BIT SHIFT
REGISTER
OUTPUT REGISTER
MAX3950
Pin Description (continued)
DATA
CLK
DIVIDE BY 4
Figure 4. Functional Block Diagram
Detailed Description
The MAX3950 deserializer implements a shift-registerbased demultiplexer to convert 9.953Gbps serial data
to 16-bit-wide, 622.08Mbps parallel data (Figure 4).
The allocation of the serial input bits to the parallel
LVDS outputs is displayed in Figure 5.
Applications Information
Low-Voltage Differential-Signal
Outputs
The MAX3950 features LVDS outputs for interfacing
with high-speed digital circuitry. This LVDS implementation is based on the IEEE 1596.3 LVDS reduced-range
link specification and is compatible with OIF 1999.102.
6
Note that the PCLK polarity on the MAX3950 is inverted
relative to OIF 1999.102, so that PCLK+ is equivalent to
RXCLK_N and PCLK- is equivalent to RXCLK_P.
The MAX3950 uses 300mVP-P to 500mVP-P differential
low-voltage swings to achieve fast transition times, minimize power dissipation, and improve noise immunity.
The parallel clock and data LVDS outputs (PCLK+,
PCLK-, PD_+, PD_-) require 100Ω differential DC termination between the inverting and noninverting outputs
for proper operation. Do not terminate these outputs to
ground. For more information on interfacing with the
LVDS outputs, refer to Maxim Application Note HFAN1.0: Interfacing Between CML, PECL, and LVDS.
_______________________________________________________________________________________
+3.3V, 10.7Gbps 1:16 Deserializer
with LVDS Outputs
D14
MAX3950
D15
D13
SD
PCLK+
(LSB) PD0
D0
D16
D32
D48
D64
PD1
D1
D17
D33
D49
D65
D15
D31
D47
D63
D79
•
•
•
(MSB) PD15
TRANSMITTED FIRST
Figure 5. Timing Diagram
VCC
250fF
50Ω
50Ω
1.1nH
SD+
K = 0.4
HIGH Z
SD1.1nH
250fF
70fF
HIGH Z
70fF
NOTE: PARASITIC VALUES SHOWN ARE TYPICAL VALUES.
Figure 6. CML Input Model
Current Mode Logic (CML) Inputs
Layout Considerations
The differential serial inputs to the MAX3950 are CML
and have an input impedance of 50Ω on each of the
complementary inputs. For more information on interfacing with the CML inputs, refer to Maxim Application
Note HFAN-1.0: Interfacing Between CML, PECL, and
LVDS.
For best performance, use good high-frequency layout
techniques. Filter voltage supplies, keep ground connections short, and use multiple vias where possible.
Use controlled-impedance transmission lines to interface with the MAX3950’s high-speed inputs and outputs. Place power-supply decoupling as close to VCC
as possible. To reduce feedthrough, isolate the input
signals from the output signals.
Interface Models
Figures 6 and 7 show the typical input/output models
for the MAX3950 deserializer.
_______________________________________________________________________________________
7
+3.3V, 10.7Gbps 1:16 Deserializer
with LVDS Outputs
MAX3950
Chip Information
TRANSISTOR COUNT: 4800
vcc
vcc
PD_+
vcc
PD_-
MAX3950
Figure 7. LVDS Output Model
Pin Configuration
GND
1
51 GND
GND
2
50 VCC
PD15-
3
49 PD9+
PD15+
4
48 PD9-
GND
5
47 PD8+
VCC
6
46 PD8-
SD+
7
45 PD7+
SD-
8
44 PD7-
VCC
9
MAX3950
43 VCC
SCLK+ 10
42 GND
SCLK- 11
41 PD6+
VCC 12
40 PD6-
GND 13
39 PD5+
PCLK- 14
38 PD5-
PCLK+ 15
37 VCC
GND 16
36 GND
35 GND
GND
GND
VCC
VCC
PD4+
PD4-
PD3+
PD3-
GND
VCC
PD2+
PD2-
PD1-
GND
PD0-
*EXPOSED PAD IS CONNECTED TO GND.
PD1+
19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34
PD0+
18
C.
N.
N.
C.
GND 17
8
C.
GND
61 60 59 58 57 56 55 54 53 52
N.
GND
VCC
VCC
PD10+
PD10-
PD11-
PD11+
GND
VCC
PD12-
PD12+
PD13-
67 66 65 64 63 62
PD13+
68
PD14-
PD14+
C.
N.
GND
TOP VIEW
QFN*
_______________________________________________________________________________________
+3.3V, 10.7Gbps 1:16 Deserializer
with LVDS Outputs
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
9 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2002 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
MAX3950
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)