MAXIM MAX3940E/D

19-2730; Rev 0; 1/03
10Gbps EAM Driver with Integrated
Bias Network
Features
♦ On-Chip Bias Network
♦ 23ps Edge Speed
♦ Programmable Modulation Voltage Up to 3VP-P
♦ Programmable EAM Biasing Voltage Up to 1.25V
♦ Selectable Data-Retiming Latch
♦ Up to 10.7Gbps Operation
♦ Integrated Modulation and Biasing Functions
♦ 50Ω On-Chip Input and Output Terminations
♦ Pulse-Width Adjustment
♦ Enable and Polarity Controls
♦ ESD Protection
Ordering Information
PART
MAX3940E/D
TEMP RANGE
PIN-PACKAGE
-40°C to +85°C
Dice*
*Dice are designed to operate over a -40°C to +120°C junction
temperature (TJ) range, but are tested and guaranteed at
TA = +25°C only.
Applications
SONET OC-192 and SDH STM-64 Transmission
Systems
DWDM Systems
Long/Short-Reach Optical Transmitters
10Gbps Ethernet
Typical Application Circuit
-5.2V
PLRT
0.01µF
50Ω
DATA+
MODEN
RTEN
GND
DATA+
EAM
0.01µF
MAX3952
DATA-
10Gbps
SERIALIZER
50Ω
DATA-
50Ω
CLK+
50Ω
CLK-
MAX3940
0.01µF
CLK+
OUT
50Ω
0.01µF
CLK-
PWC+
PWC2kΩ
-5.2V
MODSET
BIASSET
+
VMODSET
-
+
VBIASSET
-
VEE
-5.2V
-5.2V
330pF
0.1µF
REPRESENTS A CONTROLLED-IMPEDANCE TRANSMISSION LINE.
________________________________________________________________ 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
MAX3940
General Description
The MAX3940 is designed to drive an electro-absorption modulator (EAM) at data rates up to 10.7Gbps. It
incorporates the functions of a biasing circuit and a
modulation circuit, with integrated control op amps
externally programmed by DC voltages.
The integrated bias circuit provides a programmable
biasing current up to 50mA. This bias current reflects a
bias voltage of up to 1.25V on an external 50Ω load. The
bias and modulation circuits are internally connected on
chip, eliminating the need for an external bias inductor.
A high-bandwidth, fully differential signal path is internally
implemented to minimize jitter accumulation. When a
clock signal is available, the integrated data-retiming
function can be selected to reject input-signal jitter.
The MAX3940 receives differential CML signals (ground
referenced) with on-chip line terminations of 50Ω. The
output has a 50Ω resistor for back termination and is
able to deliver a modulation current of 40mA P-P to
120mAP-P, with an edge speed of 23ps (typical, 20% to
80%). This modulation current reflects an EAM modulation voltage of 1.0VP-P to 3.0VP-P.
The MAX3940 also includes an adjustable pulse-width
control circuit to precompensate for asymmetrical EAM
characteristics.
MAX3940
10Gbps EAM Driver with Integrated
Bias Network
ABSOLUTE MAXIMUM RATINGS
Current into or out of OUT..............................……………...80mA
Storage Temperature Range .....................……-55°C to +150°C
Operating Junction Temperature Range....……-55°C to +150°C
Processing Temperature (die)....................………………+400°C
Supply Voltage VEE ..............................................-6.0V to +0.5V
Voltage at MODEN,
RTEN, PLRT, MODSET, BIASSET ...........(VEE - 0.5V) to +0.5V
Voltage at DATA+, DATA-, CLK+, and CLK-……-1.65V to +0.5V
Voltage at OUT .............................................……….-4V to +0.5V
Voltage at PWC+, PWC- ...................(VEE - 0.5V) to (VEE + 1.7V)
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.
ELECTRICAL CHARACTERISTICS
(VEE = -5.5V to -4.9V, TA = -40°C to +85°C. Typical values are at VEE = -5.2V, IBIAS = 30mA, IMOD = 100mA, and TA = +25°C, unless
otherwise noted.)
PARAMETER
Power-Supply Voltage
Supply Current
Power-Supply Noise Rejection
SYMBOL
CONDITIONS
VEE
IEE
PSNR
MIN
TYP
-5.5
Excluding IBIAS and
IMOD (Note 1)
MAX
UNITS
-4.9
V
Retime disabled
122
170
Retime enabled
139
195
f ≤ 10MHz (Note 2), see Figure 4
12
mA
dB
SIGNAL INPUT (Note 3)
Input Data Rates
Single-Ended Input Resistance
NRZ
RIN
Single-Ended Input Voltage
VIS
Differential Input Voltage
VID
Differential Input Return Loss
RLIN
10.7
42.5
DC-coupled, Figure 1a
-1
0
AC-coupled, Figure 1b
-0.4
+0.4
DC-coupled (Note 4)
0.2
2.0
AC-coupled (Note 4)
0.2
1.6
(Note 3)
50
Gbps
Input to GND (Note 3)
≤ 10GHz
17
10GHz < f ≤ 15GHz
10
58.5
Ω
V
VP-P
dB
EAM BIAS
Maximum Bias Current
VBIASSET = VEE + 2V
Minimum Bias Current
VBIASSET = VEE
BIASSET Voltage Range
VBIASSET
Equivalent Bias Resistance
RBSEQV
Bias-Current-Setting Accuracy
VEE
(Note 6)
mA
1
VEE + 2
VBIASSET = VEE + 0.11V
2.1
3.9
VBIASSET = VEE + 0.36V
8.8
11.2
VBIASSET = VEE + 2.0V
52
58
VBIASSET < VEE + 0.36V
-1300
+1300
VBIASSET ≥ VEE + 0.36V
-480
+480
50Ω driver load, VBIASSET = VEE + 0.55V,
Figure 2
mA
V
Ω
36.4
BIASSET Input Resistance
BIASSET Bandwidth
55
0.3
(Note 5)
TA = +25°C
Bias-Current Temperature
Stability
50
mA
ppm/°C
20
kΩ
5
MHz
EAM MODULATION
Maximum Modulation Current
VMODSET = VEE + 1V
Minimum Modulation Current
VMODSET = VEE
MODSET Voltage Range
VMODSET
Equivalent Modulation Resistance
RMODEQV
2
120
127
38
VEE
(Note 7)
11.1
_______________________________________________________________________________________
mAP-P
40
mAP-P
VEE + 1
V
Ω
10Gbps EAM Driver with Integrated
Bias Network
(VEE = -5.5V to -4.9V, TA = -40°C to +85°C. Typical values are at VEE = -5.2V, IBIAS = 30mA, IMOD = 100mA, and TA = +25°C, unless
otherwise noted.)
PARAMETER
SYMBOL
CONDITIONS
MIN
Modulation depth 10%, 50Ω driver load,
see Figure 2
Modulation Set Bandwidth
MODSET Input Resistance
Modulation-Current Temperature
Stability
(Note 6)
Modulation-Current Setting Error
Output Resistance
OUT to GND
20
kΩ
50
BIASSET = VEE, MODEN = VEE, MODSET =
VEE, DATA+ = high, DATA- = low
Total Off Current
Output Return Loss
RLOUT
IBIAS = 30mA,
IMOD = 50mA
tSU, tHD
Figure 3 (Note 6)
Output Edge Speed
≤ 5GHz
Pulse-Width Adjustment Range
(Notes 6, 8)
Pulse-Width Control Input Range
(Single Ended)
For PWC+ and PWC-
Pulse-Width Control Input Range
(Differential)
δ
Output Overshoot
+480
ppm/°C
+5
%
58.5
Ω
1
mA
8
20% to 80% (Notes 6, 8)
Setup/Hold Time
23
dB
32
25
±20
UNITS
MHz
-5
42.5
MAX
5
-480
50Ω driver load, TA = +25°C
ROUT
TYP
ps
ps
±50
ps
VEE +
0.5
VEE +
1.5
V
(PWC+) - (PWC-)
-0.5
+0.5
V
(Notes 6, 8)
-10
+10
%
Driver Random Jitter
RJDR
(Note 6)
0.3
1.1
psRMS
Driver Deterministic Jitter
DJDR
PWC- = GND (Notes 6, 9)
6.8
14
psP-P
CONTROL INPUTS
Input High Voltage
VIH
(Note 10)
Input Low Voltage
VIL
(Note 10)
Input Current
(Note 10)
VEE +
2.0
-80
V
VEE +
0.8
V
+80
µA
Note 1: Supply current remains elevated once the retiming function has been enabled. Power must be cycled to reduce supply
current after the retiming function has been disabled.
Note 2: Power-supply noise rejection is specified as PSNR = 20Log(Vnoise (on Vcc) / ∆VOUT). VOUT is the voltage across a 50Ω load.
Vnoise (on Vcc) = 100mVP-P.
Note 3: For DATA+, DATA-, CLK+, and CLK-.
Note 4: CLK input characterized at 10.7Gbps
Note 5: RBSEQV = (VBIASSET - VEE) / IOUT with MODEN = VEE, DATA+ = high, and DATA- = low.
Note 6: Guaranteed by design and characterization using the circuit shown in Figure 4.
Note 7: RMODEQV = (VMODSET - VEE) / (IOUT - 37mA) with BIASSET = VEE.
Note 8: 50Ω load, characterized at 10.7Gbps with a 1111 1111 0000 0000 pattern.
Note 9: Deterministic jitter is defined as the arithmetic sum of PWD (pulse-width distortion) and PDJ (pattern-dependent jitter).
Measured with a 10.7Gbps 27 - 1 PRBS pattern with eighty 0s and eighty 1s inserted in the data pattern.
Note 10: For MODEN and PLRT.
_______________________________________________________________________________________
3
MAX3940
ELECTRICAL CHARACTERISTICS (continued)
10Gbps EAM Driver with Integrated
Bias Network
MAX3940
Test Circuits and Timing Diagrams
0V
100mV
1.0V
-0.5V
-1.0V
(a) DC-COUPLED SINGLE-ENDED CML INPUT
0.4V
800mV
0V
-0.4V
100mV
(b) AC-COUPLED SINGLE-ENDED (CML OR PECL) INPUT
Figure 1. Definition of Single-Ended Input Voltage Range
0V
0V
VOUT
VOUT
VBIASSET
(a) MODULATING BIASSET
(c) RESULT OF MODULATING BIASSET
AND MODSET 180° OUT OF PHASE
0V
VOUT
mW
VMODSET
(b) MODULATING MODSET
POUT
(d) RESULTING OPTICAL OUTPUT
NOTE: ALL AMPLITUDES ARE RELATIVE
Figure 2. Modulating BIASSET and MODSET pads
4
_______________________________________________________________________________________
10Gbps EAM Driver with Integrated
Bias Network
CLK+
CLK-
tSU
VIS = 0.1VP-P TO 1VP-P
DC-COUPLED
0.1VP-P TO 0.8VP-P
AC-COUPLED
tHD
DATA-
VIS
DATA+
(DATA+) (DATA-)
VID = 0.2VP-P TO 2VP-P
DC-COUPLED
0.2VP-P TO 1.6VP-P
AC-COUPLED
IOUT
IMOD = 40mAP-P TO 120mAP-P
IBIAS = 0mA TO 50mA
NOTE: IOUT RELATES TO RETIMED DATA
Figure 3. Setup and Hold Timing Definition
GND
50Ω
ROUT
50Ω
50Ω
OUT
50Ω
OSCILLOSCOPE
50Ω
50Ω
50Ω
50Ω
PATTERN
GENERATOR
DATA+
ZL
50Ω
DATA-
IMOD
IBIAS
MAX3940
VEE
VEE
VEE
MODSET
BIASSET
-5.2V
0.1µF
300pF
VEE
VEE
Figure 4. AC Characterization Circuit
_______________________________________________________________________________________
5
MAX3940
Test Circuits and Timing Diagrams (continued)
10Gbps EAM Driver with Integrated
Bias Network
MAX3940
Test Circuits and Timing Diagrams (continued)
VOLTAGE
GND
VBIAS
VMOD
VOUT
USABLE RANGE
VEE + 1.67V
BELOW USABLE RANGE
Figure 5. Bias and Modulation Relationship to EAM Voltage
Typical Operating Characteristics
(Typical values are at VEE = -5.2V, IBIAS = 30mA, IMOD = 100mA, TA = +25°C, unless otherwise noted.)
10.3Gbps OPTICAL EYE DIAGRAM
MAX3940 toc02
MAX3940 toc01
10Gbps ELECTRICAL EYE DIAGRAM
(VMOD = 3VP-P, 231 - 1 PRBS)
MAX3940 toc03
10Gbps ELECTRICAL EYE DIAGRAM
(VMOD = 1VP-P, 231 - 1 PRBS)
ASIP, INC.
20ps/div
20ps/div
20ps/div
PULSE WIDTH vs. RPWC
160
150
IEE (mA)
RETIMING ENABLED
140
130
120
RETIMING DISABLED
110
MEASURED AT 1.25Gbps
WITH A 1010 PATTERN
840
830
0
820
810
800
790
780
770
760
100
750
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90
TEMPERATURE (°C)
6
850
PULSE-WIDTH POSITIVE PULSE (ps)
MAX3940 toc04
170
RPWC- (Ω)
2000 1750 1500 1250 1000 750 500 250
MAX3940 toc05
SUPPLY CURRENT vs. TEMPERATURE
(50Ω LOAD, EXCLUDES IBIAS, IMOD)
0
250 500 750 1000 1250 1500 1750 2000
RPWC+ (Ω)
_______________________________________________________________________________________
10Gbps EAM Driver with Integrated
Bias Network
VMOD vs. VMODSET
(ZL = 50Ω)
PULSE-WIDTH DISTORTION
vs. TEMPERATURE
4.0
MAX3940 toc07
4.5
VMODSET IS RELATIVE TO VEE
3.0
2.5
3.5
VMOD (VP-P)
PULSE-WIDTH DISTORTION (ps)
3.5
MAX3940 toc06
5.0
3.0
2.5
2.0
1.5
2.0
1.5
1.0
1.0
0.5
0.5
0
0
0.25
0
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90
0.50
0.75
1.00
VMODSET (V)
TEMPERATURE (°C)
VBIAS vs. VBIASSET
(ZL = 50Ω)
POWER-SUPPLY NOISE REJECTION
vs. FREQUENCY
-0.2
30
MAX3940 toc09
VBIASSET IS RELATIVE TO VEE
MAX3940 toc08
0
25
20
-0.6
PSNR (dB)
VBIAS (V)
-0.4
-0.8
-1.0
15
10
-1.2
5
-1.4
-1.6
0
0
0.5
1.0
1.5
2.0
2.5
0.1
1
VBIASSET (V)
DIFFERENTIAL S11
vs. FREQUENCY
1000
10,000
MAX3940 toc11
0
-5
-10
-20
-25
|S22| (dB)
S11 (dB)
-10
-15
100
S22 vs. FREQUENCY
(DEVICE POWERED)
MAX3940 toc10
0
-5
10
FREQUENCY (kHz)
-30
-35
-40
-15
-20
-25
-45
-50
-55
-60
-30
-35
-40
0
2
4
6
8
10 12 14 16 18 20
FREQUENCY (GHz)
0
2
4
6
8
10
FREQUENCY (GHz)
_______________________________________________________________________________________
7
MAX3940
Typical Operating Characteristics (continued)
(Typical values are at VEE = -5.2V, IBIAS = 30mA, IMOD = 100mA, TA = +25°C, unless otherwise noted.)
10Gbps EAM Driver with Integrated
Bias Network
MAX3940
Pad Description
PAD
NAME
FUNCTION
BP1, BP2,
BP4, BP5,
BP7–BP12,
BP14, BP15,
BP17–BP24,
BP26, BP27,
BP28
GND
Ground. All pads must be connected to board ground.
BP3
DATA+
Noninverting Data Input, with 50Ω On-Chip Termination
BP6
DATA-
Inverting Data Input, with 50Ω On-Chip Termination
BP13
CLK+
Noninverting Clock Input for Data Retiming, with 50Ω On-Chip Termination
BP16
CLK-
Inverting Clock Input for Data Retiming, with 50Ω On-Chip Termination
BP25
OUT
Driver Output. Provides both modulation and bias output. DC-couple to EAM.
BP29
MODEN
TTL/CMOS Modulation Enable Input. Set low or float for normal operation. Set high to put the EAM
in the absorption (logic 0) state. Contains an internal 100kΩ pulldown to VEE.
BP30
RTEN
Data-Retiming Input. Connect to VEE for retimed data. Connect to GND to bypass retiming latch.
BP31
BIASSET
Bias Current Set. Apply a voltage to set the bias current of the driver output.
BP32
MODSET
Modulation Current Set. Apply a voltage to set the modulation current of the driver output.
BP33–BP41
VEE
BP42
PWC+
Positive Input for Modulation Pulse-Width Adjustment (see the Design Procedure section).
BP43
PWC-
Negative Input for Modulation Pulse-Width Adjustment. Ground to disable the pulse-width
adjustment feature (see the Design Procedure section).
BP44
PLRT
Differential Data Polarity Swap Input. Set high or float for normal operation. Set low to invert the
differential signal polarity. Contains an internal 100kΩ pullup to GND.
Negative Supply Voltage. All pads must be connected to VEE.
Detailed Description
The MAX3940 EAM driver consists of two main parts: a
high-speed modulation driver and an EAM-biasing
block. The clock and data inputs to the driver are compatible with PECL and CML logic levels. The modulation and bias current are output through the OUT pad.
The modulation output stage is composed of a highspeed differential pair and a programmable current
source with a maximum modulation current of 120mA.
The rise and fall times are typically 23ps. The modulation
current is designed to produce an EAM voltage up to
3.0VP-P when driving a 50Ω module. The 3.0VP-P results
from 120mAP-P through the parallel combination of the
50Ω EAM load and the internal 50Ω back termination.
8
Polarity Switch
The MAX3940 includes a polarity switch. When the
PLRT pad is high or left floating, the output maintains
the polarity of the input data. When the PLRT pad is
low, the output is inverted relative to the input data.
Clock/Data Input Logic Levels
The MAX3940 is directly compatible with ground-reference CML. Either DC- or AC-coupling may be used for
CML referenced to ground. For all other logic types,
AC-coupling should be used.
Optional Data Input Latch
To reject pattern-dependent jitter in the input data, a synchronous differential clock signal should be connected to
the CLK+ and CLK- inputs, and the RTEN control input
should be connected to VEE.
_______________________________________________________________________________________
10Gbps EAM Driver with Integrated
Bias Network
Pulse-Width Control
The pulse-width control circuit can be used to compensate for pulse-width distortion introduced by the EAM.
The differential voltage between PWC+ and PWCadjusts the pulse-width compensation. The adjustment
range is typically ±50ps. Optional single-ended operation is possible by forcing a voltage on the PWC+ pad
while leaving the PWC- pad unconnected. When PWCis connected to ground, the pulse-width control circuit
is automatically disabled.
Modulation Output Enable
The MAX3940 incorporates a modulation currentenable input. When MODEN is low or floating, the modulation/bias output (OUT) is enabled. When MODEN is
high, the output is switched to the logic 0 state. The
typical enable time is 2ns and the typical disable time
is 2ns.
Design Procedure
VBIAS ≈ IBIAS ×
ZL × ROUT
ZL + ROUT
To program the desired bias current, force a voltage at
the BIASSET pad (see the Typical Application Circuit).
The resulting IBIAS current can be calculated by the following equation:
VBIASSET
36.4Ω
IBIAS ≈
The input impedance of the BIASSET pad is typically
20kΩ. Note that the minimum output voltage is VEE +
1.67V (see Figure 5).
Programming the Pulse-Width Control
Three methods of control are possible when pulse predistortion is desired to minimize distortion at the receiver.
The pulse width may be set with a 2kΩ potentiometer with
the center tapped to VEE (or equivalent fixed resistors), or
by applying a voltage to the PWC+ pad, or by applying a
differential voltage across the PWC+ and PWC- pads.
See Table 1 for the desired effect of the pulse-width setting. Pulse width is defined as (positive pulse
width)/((positive pulse width + negative pulse width)/2).
Programming the Modulation Voltage
Input Termination Requirement
The EAM modulation voltage results from IMOD passing
through the EAM impedance (ZL) in parallel with the
internal 50Ω termination resistor (ROUT).
The MAX3940 data and clock inputs are CML compatible. However, it is not necessary to drive the IC with a
standard CML signal. As long as the specified input
voltage swings are met, the MAX3940 will operate
properly.
VMOD ≈ IMOD ×
ZL × ROUT
ZL + ROUT
To program the desired modulation current, force a
voltage at the MODSET pad (see the Typical
Application Circuit). The resulting IMOD current can be
calculated by the following equation:
IMOD ≈
VMODSET
+ 37mA
11.1Ω
An internal, independent current source drives a constant
37mA to the modulation circuitry and any voltage above
VEE on the MODSET pad adds to this. The input impedance of the MODSET pad is typically 20kΩ. Note that the
minimum output voltage is VEE + 1.67V (see Figure 5).
Programming the Bias Voltage
As in the case of modulation, the EAM bias voltage
results from IBIAS passing through the EAM impedance
(ZL) in parallel with the internal 50Ω termination resistor
(ROUT).
Applications Information
Layout Considerations
To minimize loss and crosstalk, keep the connections
between the MAX3940 output and the EAM module as
short as possible. Use good high-frequency layout
techniques and multilayer boards with an uninterrupted
ground plane to minimize EMI and crosstalk. Circuit
boards should be made using low-loss dielectrics. Use
controlled-impedance lines for the clock and data
inputs as well as for the data output. Wafer capacitors
are required to filter the VEE supply. Connect the backside of the die to GND.
Table 1. Pulse-Width Control
PULSE
WIDTH
RPWC+, RPWC- FOR
RPWC+ + RPWC- = 2kΩ
VPWC+
(PWC- OPEN)
VPWC+ VPWC-
100%
RPWC+ = RPWC-
VEE + 1V
0V
>100%
RPWC+ > RPWC-
> VEE + 1V
>0V
<100%
RPWC+ < RPWC-
< VEE + 1V
<0V
_______________________________________________________________________________________
9
MAX3940
The input data is retimed on the rising edge of CLK+. If
RTEN is connected to ground, the retiming function is disabled and the input data is directly connected to the output stage. Leave CLK+ and CLK- open when retiming is
disabled.
MAX3940
10Gbps EAM Driver with Integrated
Bias Network
RTEN
MODEN
PLRT
50Ω
50Ω
50Ω
50Ω
50Ω
ROUT
50Ω
OUT
CLK+
VEE
CLK-
D
Q
ZL
0
POLARITY
MUX
PWC
DATA+
1
IMOD
DATA50Ω
IBIAS
50Ω
MAX3940
VEE
PWC+
PWC-
2kΩ
VEE
MODSET
BIASSET
+
+
VMODSET
-
VBIASSET
-
VEE
VEE
VEE
Figure 6. Functional Diagram
Interface Schematics
Laser Safety and IEC 825
Figures 7 and 8 show simplified input and output circuits of the MAX3940 EAM driver.
Using the MAX3940 EAM driver alone does not ensure
that a transmitter design is compliant with IEC 825. The
entire transmitter circuit and component selections must
be considered. Each customer must determine the level
of fault tolerance required by their application, recognizing that Maxim products are not designed or authorized
for use as components in systems intended for surgical
implant into the body, for applications intended to support or sustain life, or for any other application where the
failure of a Maxim product could create a situation where
personal injury or death may occur.
Wire Bonding Die
For high-current density and reliable operation, the
MAX3940 uses gold metalization. Make connections to
the die with gold wire only, using ball-bonding techniques.
Minimize bond-wire lengths and ensure that the span
between the ends of the bond wire does not come closer to the edge of the die than two times the bond-wire
diameter. The minimum length of the bond wires might
be constrained by the type of wire bonder used, as well
as the dimensions of the die.
To minimize inductance, keep the connections from
OUT, GND, and VEE as short as possible. This is crucial
for optimal performance.
10
______________________________________________________________________________________
10Gbps EAM Driver with Integrated
Bias Network
MAX3940
GND
GND
50Ω
50Ω
GND
MAX3940
MAX3940
50Ω
50Ω
DATA+/CLK+
GND
50Ω
GND
OUT
DATA-/CLK-
VEE
VEE
Figure 7. Simplified Input Circuit
Chip Topography/
Pad Configuration
The origin for pad coordinates is defined as the bottom
left corner of the bottom left pad. All pad locations are
referenced from the origin and indicate the center of
the pad where the bond wire should be connected.
Refer to Maxim application note HFAN-08.0.1:
Understanding Bonding Coordinates and Physical Die
Size for detailed information.
Maxim characterized this circuit with gold wire (1-mil
diameter wire) ball bonded to the pads. Die pad size is
4 mils (102µm) square, and die thickness is 8 mils
(203µm).
Figure 8. Simplified Output Circuit
Chip Information
TRANSISTOR COUNT: 2084
PROCESS: SiGe BIPOLAR
SUBSTRATE: SOI
DIE THICKNESS: 8 mils
______________________________________________________________________________________
11
10Gbps EAM Driver with Integrated
Bias Network
MAX3940
Chip Topography
PLRT
PWC-
PWC+
VEE
VEE
VEE
VEE
VEE
VEE
VEE
VEE
VEE MODSET BIASSET RTEN
MODEN
GND
GND
GND
GND
GND
DATA+
OUT
GND
GND
DATA-
GND
GND
GND
GND
GND
(0, 0)
GND
GND
GND
GND
CLK+
GND
GND
CLK-
GND
GND
GND
GND
GND
2.3mm
(90.6 mils)
12
______________________________________________________________________________________
1.6mm
(63 mils)
10Gbps EAM Driver with Integrated
Bias Network
COORDINATES (µm)
PAD
NUMBER
PAD NAME
X
BP1
GND
51.2
BP2
GND
51.2
BP3
DATA+
BP4
GND
BP5
GND
51.2
BP6
DATA-
BP7
GND
BP8
GND
COORDINATES (µm)
Y
PAD
NUMBER
PAD NAME
X
Y
933.2
BP23
GND
2028
108.6
807.2
BP24
GND
2028
234.6
51.2
681.2
BP25
OUT
2028
574.8
51.2
555.2
BP26
GND
2028
700.8
429.2
BP27
GND
2028
856.2
51.2
303.2
BP28
GND
2028
982.2
51.2
177.2
BP29
MODEN
1953.8
1140.4
51.2
51.2
BP30
RTEN
1827.8
1140.4
1140.4
BP9
GND
231.8
-63.6
BP31
BIASSET
1701.8
BP10
GND
357.8
-63.6
BP32
MODSET
1575.8
1140.4
BP11
GND
483.8
-63.6
BP33
VEE
1449.8
1140.4
BP12
GND
609.8
-63.6
BP34
VEE
1323.8
1140.4
BP13
CLK+
769.4
-63.6
BP35
VEE
1197.8
1140.4
BP14
GND
895.4
-63.6
BP36
VEE
1071.8
1140.4
BP15
GND
1021.4
-63.6
BP37
VEE
945.8
1140.4
BP16
CLK-
1147.4
-63.6
BP38
VEE
819.8
1140.4
BP17
GND
1305.2
-63.6
BP39
VEE
693.8
1140.4
BP18
GND
1431.2
-63.6
BP40
VEE
567.8
1140.4
BP19
GND
1606.2
-63.6
BP41
VEE
441.8
1140.4
BP20
GND
1732.2
-63.6
BP42
PWC+
315.8
1140.4
BP21
GND
1874
-63.2
BP43
PWC-
189.8
1140.4
BP22
GND
2028
-43.8
BP44
PLRT
63.8
1140.4
Package Information
For the latest package outline information, go to
www.maxim-ic.com/packages.
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.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 13
© 2003 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
MAX3940
Table 2. Bondpad Locations