Preliminary Information
02042-DSH-002-C Mindspeed Technologies™ September 2005
Preliminary Information/Mindspeed Proprietary and Confidential
MC2042-3
LED/Laser Driver for FDDI, Fast Ethernet, Fibre Channel, OC3/STM-1, IEEE1394
Preliminary Information
This document contains information on a new product. The parametric information, although not
fully characterized, is the result of testing initial devices.
Applications
• FDDI, fiber Channel
• Fast Ethernet, IEEE1394
• OC3/STM1
The MC2042-3 is a CMOS IC designed for high-speed LED drive in low-cost optical fiber based transmission sys-
tems. Depending on the LED used, data rates to >500Mbps can be achieved. The LED drive current is set by a
resistor. To improve LED ‘on’ time, a pre-emphasis circuit is included, which may be set via a simple RC network.
To minimize the effects of temperature on LED output power, LED drive temperature compensation can be set by
resistor over a 0 - 10,000 ppm/°C range.
Differential positive-ECL (PECL) data on the input pins can be shaped, if desired, by the differential voltage on the
Pulse Width Adjust (PWA) pins. This adjustment is continuous over a ±500 ps range. In addition, the VREF output
pin allows single-ended input to the MC2042 and provides compatibility with industry-standard FO modules.
Typical Applications Diagram
Input Data Pulse Shaping
VREF Generator
GND GND RTSET RTSET2
PEAK
VDD2
VDD1
DIN
PWA
IOUT
PWA
DIN
VREF
Current Switch and Peaking
Control
Programmable
Current Sink
IOUT
Features
• Data rates to >500 Mbps, depending on LED
• Single chip solution, available as die or in TSSOP20 or QSOP16
fabricated in deep sub-micron CMOS for lowest cost & power
consumption and long term reliability
• Programmable output current from 30 mA to 100 mA
• RC programmable pre-emphasis or ‘peaking’ circuit giving drive
current rise and fall times <500 ps
• Resistor programmable compensation for temperature dependence
of LED output power
• PECL input with optional Pulse Width Adjust
• Single-ended CMOS input compatible at low speeds
•V
REF voltage generator and output pin
• Supports most LED types (e.g. 660 to 1300 nm)
• Single +5 V to +3.3 V operation
• Available in an RoHS-compliant package
02042-DSH-002-C Mindspeed Technologies™ ii
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Preliminary Information
Note: xx represents the revision number. Please contact your local sales office for correct digits.
Typical Eye Diagram Pin Configuration
Ordering Information (1)
Part Number Package Operating Temperature
M02042-3-xxx Waffle Pack
Expanded Whole Wafer on a Ring
QSOP16
TSSOP20
QSOP16 Tape and Reel
TSSOP20 Tape and Reel
–40 °C to 85 °C
M02042G-3-xxx (2) Waffle Pack
Expanded Whole Wafer on a Ring
QSOP16
TSSOP20
QSOP16 Tape and Reel
TSSOP20 Tape and Reel
–40 °C to 85 °C
Notes:
1. Because the current Mindspeed part number standard uses an M0 prefix, it is used for ordering the MC2042 but the part is still marked as an
MC2042 device.
2. The letter “G” designator after the part number indicates that the device is RoHS-compliant.
Refer to www.mindspeed.com for additional information.
Revision History
Revision Level Date ASIC
Revision Description
C Preliminary September 2005 Minor update in new data sheet format.
ILED_ON specification changed, RoHS packaging information
B Preliminary February 2004 Revision B release.
- Revised Ordering Information, reformatted document, added references to
lead-free and RoHS-compliant packaging options to package specifications.
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
MC2042-3
PWA-
NC
DIN
DIN
VREF
RESET2
RTSET
VDD1
PWA-
NC
GND
VDD2
GND
IOUT
IOUT
IOUT
PEAK
VDD2
NC
NC
TSSOP20
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
MC2042-3
GND
VDD2
GND
IOUT
IOUT
IOUT
PEAK
VDD2
QSOP16
PWA-
VDD1
PWA+
DIN
DIN
VREF
RTSET2
RTSET
02042-DSH-002-C Mindspeed Technologies™ 1
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Preliminary Information
1.0 Product Specification
1.1 Absolute Maximum Ratings
These are the absolute maximum ratings at or beyond which the IC can be expected to fail or be damaged. Reli-
able operation at these extremes for any length of time is not implied.
Note: The package bottom must be adequately grounded to ensure correct thermal and electrical performance,
and it is recommended that vias are inserted through to a lower ground plane.
1.2 DC Characteristics
VCC = +3.3V ± 7.5% or +5V ± 7.5%, TA = -40°C to +85°C, unless otherwise noted.
Typical specifications are for VCC = 3.3V, TA = 25°C, unless otherwise noted.
Table 1-1. Absolute Maximum Ratings
Symbol Parameter Rating Units
PTOT Total power dissipation (TSSOP20) 255 mW
VCC Power supply (VCC-GND) 7V
TJJunction temperature 150 °C
TAOperating ambient -40 to +85 °C
TSTG Storage temperature -65 to +150 °C
Table 1-2. DC Characteristics
Symbol Parameter Min Typ Max Units
VCC Supply Voltage 3.0 - 5.5 V
Din Allowable voltage at data inputs Gnd - 0.3 - VCC+0.3
ILED’ ON LED drive current 30 - 100 mA
ILED’ OFF LED off current --50µA
ICOMP LED drive current temperature compensation range 0-1%/°C
V_LED_H minimum allowable voltage at IOUT VDD-2.0 --V
Product Specification
02042-DSH-002-C Mindspeed Technologies™ 2
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Preliminary Information
1.3 AC Characteristics
VCC = +3.3V ± 7.5% or +5V ± 7.5%, TA = -40°C to +85°C, input bit rate = 1.25 Gbps 223-1 PRBS unless
otherwise noted. Typical specifications are for VCC = 3.3V, TA = 25°C, unless otherwise noted.
Table 1-3. AC Characteristics
Symbol Parameter Min Typ Max Units
Vin(Diff) Differential Input Voltage, 2*(DinH - DinL) 300mV - 2*Vcc V
Common Mode Input Voltage VCC/2 -(Vcc-(Vin[Diff])/4) V
fCMaximum data rate 300 - - Mbps
TPWA Input data pulse width adjust range -500 - 500 ps
LED trLED drive rise time -- 1 ns
LED tfLED drive fall time -- 1 ns
IPEAK Peaking current (as % of LED drive current) 0- 50 %
PEAK trPeaking current rise time -- 1 ns
PEAK tfPeaking current fall time -- 1 ns
PEAK tdPeaking current decay time - C1x(R4+5) - S
IDD Supply current -- ILED+20 mA
02142-DSH-002-C Mindspeed Technologies™ 3
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2.0 Pin Definitions
Table 2-1. Pin Descriptions
TSSOP20
Pin
QSOP16
Pin
Die
Pin Name Description
1--NCNot connected, leave open
2113PWAInverse pulse width adjust input
3214PWA
Differential pulse width adjust input. Allows continuous adjustment of
input data pulse width
4315
DIN Differential data input
5416
DIN Inverse differential data input
651
VREF Reference output. Can be used with single-ended data input
762
RTSET2 Temperature compensation adjustment pin. Allows temperature
dependence of LED light output to be reduced or removed
873
RTSET Sets nominal LED drive current
984
VDD1 Power pin, connect to most positive supply
10 - - NC Not connected
11 - - NC Not connected
12 9 5 VDD2 LED shorting pin, connect to most positive supply. Speeds LED
switch off
13 10 6 VDD2 LED shorting pin, connect to most positive supply. Speeds LED
switch off
14 11 7 PEAK Connection for pre-emphasis or peaking circuit
15 12 8 IOUT Driver output. Connect LED between this pin and VDD
16 13 9 IOUT Driver output. Connect LED between this pin and VDD
17 14 10 IOUT
Logical inverse of pin Iout. Connect resistor of approximately the
same value as LED (at the programmed drive current level) between
this pin and VDD
18 15 11 GND Ground pin. Connect to the most negative supply
19 16 12 GND Ground pin. Connect to the most negative supply
20 - - NC Not connected, leave open
Pin Definitions
02142-DSH-002-C Mindspeed Technologies™ 4
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Figure 2-1. Bare Die
Table 2-2. Bare Die Pad Coordinates
Pad Description X Y Pad Description X Y
1VREF -73 394.5 9 IOUT 73 -394.5
2RTSET2 -219 394.5 10 IOUT 219 -394.5
3RTSET -397 214.7 11 GND 397 -223.3
4VDD1 -397 68.7 12 GND 397 -77.3
5VDD2 -397 -77.3 13 PWA 397 68.7
6VDD2 -397 -223.3 14 PWA 397 214.7
7PEAK -219 -394.5 15 DIN 219 394.5
8IOUT -73 -394.5 16 DIN 73 394.5
RTSET
VDD1
PEAK
IOUT
GND
PWA
DIN
VREF
VDD2
VDD2
IOUT
IOUT
GND
PWA
DIN
RTSET2
1
2
3
4
5
6
789
10
11
12
13
14
15
16
Die size: 1.0 x 1.0 mm
Pad openings: 95 um square
02042-DSH-002-C Mindspeed Technologies™ 5
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Preliminary Information
3.0 Functional Description
3.1 Overview
The MC2042-3 is a CMOS IC designed for high-speed LED drive in low-cost optical fiber based transmission sys-
tems. Depending on the LED used, data rates to >500 Mbps can be achieved.
The LED drive current is set by a resistor. To improve LED ‘on’ time, a pre-emphasis circuit is included, which may
be set via a simple RC network.
To minimize the effects of temperature on LED output power, LED drive temperature compensation can be set by
resistor over a 0 - 10,000 ppm/°C range.
Differential positive-ECL (PECL) data on the input pins can be shaped, if desired, by the differential voltage on the
Pulse Width Adjust (PWA) pins. This adjustment is continuous over a ±500 ps range. In addition, the VREF output
pin allows single-ended input to the MC2042 and provides compatibility with industry-standard FO modules.
3.1.1 Signal Path Description
Differential Positive-ECL (PECL) data on the data input pins controls the LED current switch. The LED current flows
either through the LED or via the dummy load so that VDD noise is minimized. To reduce LED ‘turn-off’ time, the
LED is momentarily short-circuited, via VDD2, before the current is switched to the dummy load.
3.1.2 Data Inputs
Data inputs DIN and /DIN are compatible with standard CMOS logic as well as differential logic families. These
inputs may be used in a differential or single-ended configuration. If the inputs are to be used single-ended, the
unused input should be connected to pin VREF. VREF should not be loaded by external current sources or sinks.
3.1.3 LED Drive and Temperature Compensation
The LED drive current and temperature compensation is set by the two resistors R1 and R2. The simplified applica-
tion diagram (Figure 3) shows R1 connected between RTSET and GND, and R2 between RTSET and the RTSET2
pin.
The current flowing out of the RTSET pin determines the LED drive current.
The temperature independent component of the LED drive current is set primarily by R1. The temperature depen-
dent component by R2. However, R1 and R2 are not independent.
The RTSET2 pin connects to an internal diode on the IC which exhibits standard diode behaviour with temperature.
As temperature rises, the voltage on the diode drops, the current flowing through R2 increases and the LED drive
current increases.
Functional Description
02042-DSH-002-C Mindspeed Technologies™ 6
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Preliminary Information
Given the various interdependencies of the drive current, R1, R2, and temperature compensation, the relationships
have been tabulated (see Temperature Compensation table). Please contact Mindspeed if other combinations are
required.
The LED 'on' current is controlled to ±10%.
A Microsoft Excel file is available from Mindspeed which will calculate appropriate values for RTset resistors R1
and R2 given your LED current, forward voltage, and LED temperature coefficient. The file may be obtained from a
Mindspeed Field Applications Engineer and is named 'MC2042-3 resistor selection.xls'. See section Te m p e r a -
ture Compensation Tables if the spreadsheet is not available.
3.1.4 Transmit Enable/Disable
There is no dedicated pin on the MC2042 to disable the LED drive current. However, the LED drive current can be
disabled by disabling the current out of pin RTSET. The LED current is approximately 100x the current out of pin
RTSET, so if the current out of this pin is 0, the LED drive current is 0. However, if peaking is used the peaking cur-
rent will not be disabled.
Figure 3-2 illustrates how the current out of RTSET can be disabled by adding a MOSFET (Q1) at the RTSET node
of the R1/R2 temperature compensation network. The voltage on the gate of Q1 then controls transmit enable/dis-
Figure 3-1. LED Drive and Temperature Compensation
R1
R2
RTSET
RTSET2
(unused)
External Diode
for Temp. Comp.
Functional Description
02042-DSH-002-C Mindspeed Technologies™ 7
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Preliminary Information
able. When selecting Q1, a MOSFET should be chosen with an Rds(on) which is negligible compared to R1 and
R2.
3.1.5 Pre-Emphasis Or ‘Peaking’
To improve LED ‘turn on’ time an optional pre-emphasis function is included on the MC2042-3. If this is not
required, then the PEAK pin should be left floating. Two external components (R4, C1) are required as shown in
Figure 4-1 to implement peaking.
When the LED is turned on, the voltage on PEAK is pulled LOW very rapidly. This voltage transient is coupled
through R4 and C1 and exerts a transient current on the LED. When the LED is turned off, the voltage on PEAK is
pulled HIGH rapidly. This voltage transient is coupled through R4 and C1 and exerts a transient current in the oppo-
site direction on the LED.
The transient current amplitude and RC decay are given approximately by:
Peak current (Amps): 4/(R4 + 5)
Decay (seconds): C1 x (R4 + 5)
The above approximations assume an ideal LED model with 0 Ohms resistance. Real LEDs will slightly alter the
peaking effect. Typical values for R4 and C1 are:
R4 = 50 Ω
C1 = 20 pF
3.1.6 LED Clamping, Laser Driving
Since most LEDs exhibit a longer ‘turn off’ time than ‘turn on’ time, a clamping function is included on the MC2042
in order to reduce the ‘turn off’ time. Clamping is enabled via the two VDD2 connections.
The disadvantage of clamping is that the LED’s internal capacitance has to be fully charged again before the LED
starts to emit light. This delayed ‘turn on’ effect becomes noticeable when the nominal LED drive current is low.
Use of the peaking circuit helps solve this problem. Thus, the combination of peaking and clamping results in very
fast ‘turn on’ and ‘turn off’ times for the LED.
Figure 3-2. Transmit Enable/Disable
R1
R2
RTSET RTSET2
Transmit Enable
Functional Description
02042-DSH-002-C Mindspeed Technologies™ 8
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Preliminary Information
When driving lasers, it will often be helpful to disable this clamping. This can be achieved by leaving the VDD2 con-
nections floating. VDD1 must still be connected.
3.1.7 LED Drive Pulse Width Adjust (PWA)
The input pulse width can be adjusted prior to application to the LED switch. The differential voltage on the PWA
(Pulse Width Adjust) pins shapes the input pulse linearly over a nominal -500 to +500 ps range, according to the
formula:
Delta PW (ps) = K x VPWA
Where:
K = 500 ± 100
and
VPWA = (VPWA+) - (VPWA-)
The maximum range for VPWA is ±1V. The input impedance is 3.6 kΩ. VPWA+ and VPWA- will settle at a nominal
voltage equal to (0.6 * VDD) if left floating. It is recommended that adjustment be implemented by pull down resis-
tors on PWA+ or PWA-. However, it is common for one or other pin to be tied to ground as a zero-cost, ‘gross’
adjustment.
If pulse width adjustment is not required PWA+ and PWA- should be tied to ground.
3.1.8 Eye Diagram
The eye diagram below is typical of the electrical output of the MC2042-3. The crossover point can be moved up
and down using the PWA pin. The overshoot can be increased by using the PEAK pin.
Figure 3-3. Eye Diagram
Functional Description
02042-DSH-002-C Mindspeed Technologies™ 9
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Preliminary Information
3.1.9 Temperature Compensation Tables
An EXCEL spreadsheet is available for selecting resistor values for temperature compensation. See the Mind-
speed website or contact your Mindspeed representative to obtain a copy of the M02042-3 Resistor Selection Util-
ity. Alternatively, the table below can be used to select resistor values. Refer to Ta bl e 3-1 and choose the desired
ILED at two different die temperatures to select appropriate R1/R2 values.
Note: The tables are based on MC2042-3 junction temperatures (Tj), at 50° and 125°C. The user must take into
account the power dissipation and thermal resistance to arrive at the die temperature.
Example, at Vcc=5v:
Then R1=3300, R2= 270 ohms (shaded) is one possible solution.
Ambient 25 85 °C
Iled 70 100 mA
VLed 1.5 1.5 v
Pstatic 50 50 mW
Pdynamic (Vcc-VLed)*(70) = 245 350 mW
Rt 100 100 °C/Watt
Tj Ta+24.5+5 = 54.5 85+35+5 = 125 °C
Functional Description
02042-DSH-002-C Mindspeed Technologies™ 10
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Preliminary Information
Table 3-1. Temperature Compensation Tables
Tj=50 1800 2200 2700 3300 3900 4700 5600 6800 8200 10000 12000 15000 18000 22000 27000 33000 39000 47000
47 135.9 131.4 127.7 124.7 122.7 120.8 119.3 117.9 116.9 115.9 115.2 114.5 114 113.6 113.2 112.9 112.7 112.5
56 130.8 126.1 122.3 119.2 117.1 115.1 113.5 112.1 111 110 109.2 108.5 108 107.5 107.1 106.8 106.6 106.4
68 125 120.1 116.1 112.9 110.6 108.6 106.9 105.4 104.3 103.2 102.4 101.6 101.1 100.6 100.2 99.92 99.7 99.49
82 119.4 114.3 110.1 106.7 104.4 102.2 100.5 98.92 97.67 96.58 95.76 94.93 94.39 93.89 93.47 93.14 92.91 92.7
100 113.4 108 103.6 100.1 97.68 95.4 93.62 91.98 90.68 89.54 88.68 87.81 87.24 86.72 86.28 85.93 85.69 85.47
120 107.9 102.4 97.81 94.14 91.61 89.24 87.39 85.68 84.32 83.14 82.24 81.34 80.74 80.2 79.75 79.38 79.13 78.9
150 101.4 95.68 90.87 87.04 84.38 81.9 79.96 78.17 76.75 75.51 74.56 73.62 73 72.42 71.95 71.57 71.31 71.06
180 96.38 90.41 85.44 81.47 78.72 76.14 74.13 72.28 70.8 69.51 68.53 67.56 66.91 66.31 65.82 65.43 65.15 64.9
220 91.09 84.92 79.76 75.64 72.79 70.12 68.03 66.1 64.57 63.23 62.21 61.2 60.52 59.91 59.39 58.98 58.7 58.44
270 86.06 79.68 74.35 70.08 67.12 64.36 62.19 60.19 58.6 57.21 56.16 55.11 54.4 53.77 53.23 52.81 52.51 52.24
330 81.51 74.94 69.44 65.04 61.99 59.13 56.89 54.82 53.18 51.74 50.65 49.56 48.83 48.17 47.62 47.18 46.88 46.59
390 78.03 71.3 65.68 61.17 58.04 55.11 52.81 50.69 49 47.52 46.4 45.28 44.54 43.86 43.29 42.84 42.53 42.23
470 74.46 67.58 61.82 57.19 53.98 50.97 48.61 46.43 44.69 43.18 42.02 40.87 40.1 39.41 38.82 38.36 38.04 37.74
560 71.43 64.41 58.52 53.79 50.51 47.43 45.01 42.78 41 39.45 38.26 37.08 36.29 35.58 34.98 34.5 34.17 33.86
680 68.4 61.24 55.23 50.4 47.04 43.88 41.4 39.12 37.29 35.7 34.48 33.27 32.46 31.73 31.11 30.62 30.28 29.97
820 65.8 58.52 52.4 47.47 44.04 40.82 38.29 35.95 34.08 32.45 31.21 29.97 29.14 28.38 27.76 27.25 26.91 26.58
1000 63.37 55.97 49.74 44.72 41.23 37.94 35.35 32.96 31.05 29.38 28.11 26.84 25.99 25.22 24.58 24.06 23.71 23.37
1200 61.41 53.91 47.59 42.5 38.94 35.6 32.96 30.53 28.59 26.88 25.58 24.29 23.42 22.63 21.98 21.45 21.09 20.75
1500 59.33 51.72 45.31 40.12 36.51 33.1 30.41 27.93 25.94 24.2 22.87 21.55 20.66 19.85 19.18 18.64 18.27 17.92
1800 57.86 50.18 43.69 38.45 34.78 31.33 28.6 26.08 24.06 22.29 20.94 19.59 18.69 17.87 17.18 16.63 16.25 15.9
2200 56.46 48.7 42.15 36.84 33.13 29.63 26.87 24.31 22.26 20.46 19.08 17.71 16.79 15.95 15.26 14.7 14.31 13.95
2700 55.23 47.42 40.8 35.44 31.69 28.15 25.35 22.75 20.67 18.84 17.45 16.05 15.11 14.26 13.55 12.98 12.59 12.22
3300 54.21 46.34 39.68 34.27 30.48 26.9 24.07 21.44 19.33 17.48 16.06 14.65 13.7 12.83 12.11 11.53 11.13 10.76
3900 53.48 45.57 38.87 33.42 29.61 26 23.15 20.5 18.37 16.5 15.07 13.63 12.67 11.79 11.06 10.48 10.07 9.692
4700 52.77 44.82 38.08 32.61 28.77 25.13 22.26 19.58 17.43 15.54 14.09 12.64 11.67 10.78 10.04 9.448 9.036 8.65
Tj=125 1800 2200 2700 3300 3900 4700 5600 6800 8200 10000 12000 15000 18000 22000 27000 33000 39000 47000
47 182.3 181.2 180.2 179.3 178.7 178.1 177.6 177.1 176.7 176.3 176.1 175.8 175.6 175.4 175.3 175.2 175.1 175
56 179.2 177.7 176.3 175.1 174.3 173.4 172.7 172 171.5 171 170.6 170.3 170 169.8 169.6 169.4 169.3 169.2
68 174.6 172.5 170.6 168.9 167.7 166.5 165.5 164.6 163.9 163.2 162.7 162.2 161.9 161.6 161.3 161.1 160.9 160.8
82 168.8 166 163.4 161.2 159.6 158.1 156.9 155.7 154.7 153.9 153.2 152.6 152.1 151.7 151.4 151.1 150.9 150.8
100 161.1 157.4 154.1 151.3 149.4 147.5 146.1 144.7 143.6 142.6 141.9 141.2 140.7 140.2 139.8 139.5 139.3 139.1
120 152.8 148.4 144.6 141.6 139.4 137.3 135.7 134.2 132.9 131.9 131.1 130.2 129.7 129.2 128.8 128.4 128.2 128
150 141.9 137 132.7 129.3 126.8 124.5 122.7 121 119.7 118.5 117.6 116.7 116.1 115.6 115.1 114.8 114.5 114.3
180 133 127.6 123.1 119.3 116.7 114.3 112.4 110.6 109.2 108 107.1 106.1 105.5 104.9 104.5 104.1 103.8 103.6
220 123.4 117.7 112.8 108.9 106.2 103.7 101.7 99.84 98.37 97.08 96.11 95.13 94.48 93.89 93.39 93 92.72 92.47
270 114.2 108.2 103.1 99.07 96.26 93.61 91.54 89.62 88.09 86.75 85.74 84.72 84.04 83.42 82.91 82.49 82.21 81.94
330 105.9 99.67 94.44 90.24 87.32 84.58 82.43 80.44 78.85 77.46 76.41 75.35 74.64 74 73.47 73.04 72.74 72.46
390 99.6 93.2 87.83 83.52 80.51 77.69 75.48 73.43 71.8 70.36 69.28 68.19 67.46 66.8 66.25 65.81 65.5 65.22
470 93.2 86.63 81.11 76.67 73.58 70.67 68.39 66.28 64.59 63.12 61.99 60.87 60.12 59.44 58.87 58.42 58.1 57.8
560 87.79 81.06 75.41 70.86 67.69 64.71 62.36 60.19 58.46 56.95 55.79 54.64 53.87 53.17 52.58 52.11 51.79 51.49
680 82.43 75.55 69.76 65.09 61.83 58.77 56.36 54.14 52.36 50.8 49.61 48.42 47.63 46.91 46.31 45.82 45.49 45.18
820 77.87 70.85 64.93 60.15 56.83 53.69 51.22 48.94 47.12 45.52 44.3 43.08 42.26 41.52 40.9 40.41 40.07 39.74
1000 73.63 66.47 60.43 55.55 52.15 48.94 46.41 44.07 42.2 40.56 39.31 38.06 37.22 36.46 35.83 35.32 34.97 34.64
1200 70.22 62.95 56.81 51.84 48.37 45.1 42.52 40.14 38.23 36.55 35.27 33.99 33.14 32.36 31.71 31.19 30.83 30.49
1500 66.63 59.23 52.97 47.91 44.37 41.03 38.39 35.95 33.99 32.27 30.97 29.65 28.77 27.97 27.31 26.77 26.4 26.05
1800 64.11 56.62 50.28 45.15 41.55 38.16 35.48 32.99 31 29.25 27.92 26.58 25.68 24.87 24.19 23.64 23.26 22.91
2200 61.72 54.15 47.73 42.52 38.87 35.42 32.7 30.17 28.14 26.36 25 23.63 22.72 21.89 21.19 20.63 20.25 19.88
2700 59.65 52 45.5 40.23 36.53 33.03 30.27 27.7 25.64 23.82 22.44 21.05 20.11 19.27 18.56 17.99 17.59 17.22
3300 57.93 50.21 43.65 38.32 34.58 31.04 28.24 25.63 23.54 21.7 20.29 18.87 17.93 17.06 16.34 15.76 15.36 14.98
3900 56.7 48.93 42.33 36.96 33.18 29.61 26.78 24.15 22.03 20.17 18.74 17.31 16.35 15.47 14.74 14.15 13.74 13.36
4700 55.52 47.7 41.05 35.64 31.84 28.23 25.37 22.71 20.57 18.68 17.24 15.79 14.81 13.93 13.18 12.59 12.17 11.78
02042-DSH-002-C Mindspeed Technologies™ 11
4.0 Applications Information
4.1 Typical Applications Circuit
Figure 4-1. Typical Applications Circuit
Input Data Pulse Shaping Current Switch and Peaking
Control
VREF Generator Programmable
Current Sink
GND GND2 RTSET RTSET2
IOUT PEAK
VDD2
VDD1
DIN
PWA
IOUT
PWA
DIN
R4 C1
R1
R2
LED
Dummy
LED Load
VCC
VREF
Optional Peaking
Applications Information
02042-DSH-002-C Mindspeed Technologies™ 12
4.2 Evaluation Board
An electrical evaluation board is available for the MC2042-3. The schematic is shown below.
Figure 4-2. Evaluation Board
1 2 34
A
B
C
D
4
321
D
C
B
A
MC2042-3 EVALUATION BOARD
MC2042
1
1SHEET
OF 1
DOC_NO
REV
TITLE
N/C 20
GND 19
GND 18
IOUTB 17
IOUT 16
IOUT 15
PEAK 14
VDD2 13
RTSET
8
RTSET2
7
VBB
6
DIN-
5
DIN+
4
PWA+
3
PWA-
2
N/C
1
VDD1
9
N/C
10
VDD2 12
N/C 11
IC1
MICROCOSM MC2042-3
VCC1
VCC1
C1
10NF
R1
0R
VCC2
C2
10NF
R2 N/C
R3 N/C
R4 22R
C4
18PF
C5 100NF
C3
10NF
SK1
SK2
CATHODE
ANODE
VCC2
VBB
R5
50R
R6
50R
C6
100NF
1
2
SK4
1
2
SK5
DATA INPUTS
LED INTERFACE
R8
N/C
R9
N/C
VCC1
1
2
SK6
DATA_CMOS
DATA_IN
DATA_INB
R11
N/C
R12
N/C
VCC1
R13
N/C
R14
N/C
R10
1K
R17
50K
R18
50K
R7
10K
R19
50K
C8
100NF
CAN_GND
SK3
R15
N/C
R16
N/C
C11
10NF
C12
10NF
LED PULSE WIDTH
ADJUST
SET LED
TEMP COMP
SET NOMINAL LED
DRIVE CURRENT
1
2
3
HD1
VCC1
3.3V
0V
+C10
10UF
POWER
L1
EXCCL3216U
L2
EXCCL3216U
C7
100NF
VCC2
C9
100NF
General
-------------
The board allows the user full flexibility for determining the
resistor valuesrequired for the pulse width adjust, LED current
and LED temperature compensation functions.
Controls
--------------
Pulse width adjust - R17/R18
These pots can be altered to give a total of +/- 500 pS
Pulse width adjustment. No adjustment occurs if PWA +
& PWA- are tied to gnd. Maximum adjustment in either direction
is obtained by connecting PWA+ to VCC and PWA- to gnd ,
or viceversa.
This board is provided for evaluation of the MC2042-3
LED drive current & temp compensation - R19 & R7
The drive current and temperature compensation
is determined by two potentiometers , R19 & R7
respectively .LED turn-on time can be improved by
proper selection of R2, R3 & C4. Refer to Microcosm
documentation for selection of these values.
Inputs
-----------
SK4 & SK5 are provided for the connection of
differential PECL input signals. Alternatively a CMOS
input may be connected to SK6.If using SK6, remove
R6, C5 & C6 and fit R8 & R9 with 1K resistors.
02042-DSH-002-C Mindspeed Technologies™ 13
Preliminary Information/Mindspeed Proprietary and Confidential
5.0 Package Specification
Figure 5-1. TSSOP20 Package Information
Note:
This package is available in conventional, lead-free and RoHS-compliant versions. Consult the Mindspeed.com
web site for current information.
Package Specification
02042-DSH-002-C Mindspeed Technologies™ 14
Preliminary Information/Mindspeed Proprietary and Confidential
Figure 5-2. QSOP16 Package Information
Table 5-1. TSSOP20 Dimensions
Dims. Tols/leads TSSOP20L
AMAX 1.20
A1 0.5MIN/.10MAX.
A2 NOM .90
D±.05 6.50
E±.10 6.40
E1 ±.10 4.40
L+.15/-.10 .60
L1 REF. 1.00
Zp REF. .325
eBASIC .65
b±.05 .22
c.13MIN/.20MAX
e±4° 4°
aaa MAX. .10
bbb MAX. .10
ccc MAX .05
ddd MAX. .20
Package Specification
02042-DSH-002-C Mindspeed Technologies™ 15
Preliminary Information/Mindspeed Proprietary and Confidential
Table 5-2. QSOP16 Dimensions
Dims. Tols/N QSOP16
AMAX. 1.60
A1 ±.05 0.1
A2 ±.10 1.40
D±.10 4.9
E±.20 6.00
E1 ±.10 3.90
L±.05 0.6
ccc MAX. 0.10
ddd MAX. 0.10
eBASIC 0.65
b±.05 0.25
c±.05 .2 Min.
.24 Max.
R±.05 0.20
R1 Min. 0.20
Preliminary Information
02042-DSH-002-C Mindspeed Technologies™ 16
Preliminary Information/Mindspeed Proprietary and Confidential
© 2005, Mindspeed TechnologiesTM, Inc. All rights reserved.
Information in this document is provided in connection with Mindspeed TechnologiesTM ("MindspeedTM") products.
These materials are provided by Mindspeed as a service to its customers and may be used for informational pur-
poses only. Except as provided in Mindspeed’s Terms and Conditions of Sale for such products or in any separate
agreement related to this document, Mindspeed assumes no liability whatsoever. Mindspeed assumes no respon-
sibility for errors or omissions in these materials. Mindspeed may make changes to specifications and product
descriptions at any time, without notice. Mindspeed makes no commitment to update the information and shall
have no responsibility whatsoever for conflicts or incompatibilities arising from future changes to its specifications
and product descriptions. No license, express or implied, by estoppel or otherwise, to any intellectual property
rights is granted by this document.
THESE MATERIALS ARE PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS OR
IMPLIED, RELATING TO SALE AND/OR USE OF MINDSPEED PRODUCTS INCLUDING LIABILITY OR WAR-
RANTIES RELATING TO FITNESS FOR A PARTICULAR PURPOSE, CONSEQUENTIAL OR INCIDENTAL DAM-
AGES, MERCHANTABILITY, OR INFRINGEMENT OF ANY PATENT, COPYRIGHT OR OTHER INTELLECTUAL
PROPERTY RIGHT. MINDSPEED FURTHER DOES NOT WARRANT THE ACCURACY OR COMPLETENESS
OF THE INFORMATION, TEXT, GRAPHICS OR OTHER ITEMS CONTAINED WITHIN THESE MATERIALS.
MINDSPEED SHALL NOT BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL
DAMAGES, INCLUDING WITHOUT LIMITATION, LOST REVENUES OR LOST PROFITS, WHICH MAY RESULT
FROM THE USE OF THESE MATERIALS.
Mindspeed products are not intended for use in medical, lifesaving or life sustaining applications. Mindspeed cus-
tomers using or selling Mindspeed products for use in such applications do so at their own risk and agree to fully
indemnify Mindspeed for any damages resulting from such improper use or sale.
02042-DSH-002-C Mindspeed Technologies™ 17
Preliminary Information/Mindspeed Proprietary and Confidential
Preliminary Information
www.mindspeed.com
General Information:
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International: (949) 483-6996
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4000 MacArthur Blvd., East Tower
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