View MAX374707_4127847.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

19-3297; Rev 1; 10/07
KIT ATION EVALU BLE AVAILA
155Mbps to 3.2Gbps, Low-Power SFP Limiting Amplifiers
Features
Pin Compatible with Micrel SY88993V 155Mbps to 3.2Gbps Operation > 57dB of Gain < 10-12 BER with 2mVP-P Input Amplitude 18mA Supply Current Chatter-Free LOS with Programmable Threshold Output DISABLE Function PECL-Compatible Inputs
General Description
The MAX3747/MAX3747A/MAX3747B multirate limiting amplifiers function as data quantizers for OC-3 through OC-48 synchronous optical network (SONET), FibreChannel, and Gigabit Ethernet optical receivers. They are pin-for-pin compatible with the SY88993V from Micrel Semiconductor, Inc. The amplifiers accept a wide range of input voltages and provide constant-level, current-mode logic (CML) output voltages with controlled edge speeds. The MAX3747 output voltage level is 500mVP-P and the MAX3747A/MAX3747B output voltages are 800mVP-P. The MAX3747B has enhanced LOS operation under overload conditions. The MAX3747/MAX3747A/MAX3747B limiting amplifiers feature a programmable loss-of-signal detect (LOS) and an optional disable function (DISABLE) that can be combined to implement squelch. The MAX3747/MAX3747A/MAX3747B are available in a 3mm, 10-pin MAX(R) package ideal for small formfactor receivers.
MAX3747/MAX3747A/MAX3747B
Ordering Information
PART MAX3747EUB MAX3747AEUB MAX3747BEUB TEMP RANGE -40C to +85C -40C to +85C -40C to +85C PINPACKAGE 10 MAX 10 MAX 10 MAX PKG CODE U10C-4 U10C-4 U10C-4
Applications
Gigabit Ethernet SFP/SFF Optical Transceiver Modules 1G/2G Fibre-Channel SFP/SFF Optical Transceiver Modules Multirate OC-3 to OC-48 FEC SFP/SFF Optical Transceiver Modules 10G LX4 Transceiver Modules
MAX is a registered trademark of Maxim Integrated Products, Inc. Pin Configuration appears at end of data sheet.
Typical Application Circuit
HOST BOARD SUPPLY FILTER HOST FILTER VCC_RX VCC
SFP OPTICAL RECEIVER 3-INPUT DIAGNOSTIC MONITOR
DS1859
VCC
MAX4004
0.1F
IN+
MAX3747 MAX3747A MAX3747B
OUT+
0.1F 50 0.1F 50 SERDES
MAX3745
0.1F
IN-
OUT-
5-PIN TO-HEADER 50 50 VREF TH GND LOS DISABLE 4.7k TO 10k VCC_HOST RTH1 0.1F RTH2 0.1F LOS
VCC
RTH1 + RTH2 5k
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com.
155Mbps to 3.2Gbps, Low-Power SFP Limiting Amplifiers MAX3747/MAX3747A/MAX3747B
ABSOLUTE MAXIMUM RATINGS
Power-Supply Voltage (VCC) .................................-0.5V to +4.5V Voltage at IN+, IN- ..........................(VCC - 2.4V) to (VCC + 0.5V) Voltage at DISABLE, LOS, TH, VREF ..........-0.5V to (VCC + 0.5V) Current into LOS ...................................................-1mA to +9mA Current into VREF ..................................................................2mA Differential Input Voltage (IN+ - IN-) .....................................2.5V Continuous Current at CML Outputs (OUT+, OUT-) ..............................................-25mA to +25mA Continuous Power Dissipation (TA = +70C) 10-Pin MAX (derate 6.9mW/C above +70C) ...........552mW Operating Junction Temperature Range (TJ) .......-55C to +150C Storage Ambient Temperature Range (TS)...........-55C to +150C
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
(VCC = +2.97V to +3.63V, CML output load is 50 to VCC, TA = -40C to +85C. Typical values are at VCC = +3.3V and TA = +25C, unless otherwise specified.) (Note 1)
PARAMETER POWER SUPPLY MAX3747 including the CML output current MAX3747A including the CML output current MAX3747B including the CML output current Supply Current (Note 2) ICC MAX3747/MAX3747A excluding the CML output current MAX3747B excluding the CML output current Power-Supply Noise Rejection INPUT SPECIFICATION Input Sensitivity Input Overload OUTPUT SPECIFICATION Output Resistance Differential Output Return Loss CML Differential Output Voltage Differential Output Signal When Disabled Data-Output Transition Time TRANSFER CHARACTERISTIC K28.5 pattern at 3.2Gbps PRBS 223 - 1 equivalent pattern at 2.7Gbps Deterministic Jitter (Notes 4, 5) DJ (Note 6) K28.5 pattern at 2.1Gbps PRBS 223 - 1 equivalent pattern at 155Mbps (Note 6) Random Jitter VIN = 4mVP-P (Notes 4, 7) 13.2 14 12 85 3.5 19 25 17 150 5 psRMS psP-P R OUT DUT is powered on, f < 3GHz MAX3747A/MAX3747B 4mVP-P VIN 1200mVP-P MAX3747 4mVP-P VIN 1200mVP-P AC-coupled outputs, VIN-MAX applied to the input (Note 4) 20% to 80% (Note 4) 70 600 400 42 50 15 800 500 1000 600 15 120 mVP-P ps 58 dB mVP-P VIN-MIN VIN-MAX (Note 3) (Note 3) 1200 4 mVP-P mVP-P PSNR f < 2MHz 30 36 38 18 20 30 35 41 43 24 26 dB mA SYMBOL CONDITIONS MIN TYP MAX UNITS
2
_______________________________________________________________________________________
155Mbps to 3.2Gbps, Low-Power SFP Limiting Amplifiers
ELECTRICAL CHARACTERISTICS (continued)
(VCC = +2.97V to +3.63V, CML output load is 50 to VCC, TA = -40C to +85C. Typical values are at VCC = +3.3V and TA = +25C, unless otherwise specified.) (Note 1)
PARAMETER Input-Referred Noise Low-Frequency Cutoff LOS Hysteresis LOS Assert/Deassert Time Low LOS Assert Level Low LOS Deassert Level Medium LOS Assert Level Medium LOS Deassert Level High LOS Assert Level High LOS Deassert Level TTL/CMOS I/O VREF Voltage LOS Output High Voltage LOS Output Low Voltage DISABLE Input High DISABLE Input Low DISABLE Input Current VREF VOH VOL VIH VIL RLOS = 4.7k to 10k to VCC_HOST RLOS = 4.7k RLOS = 4.7k to 10k to 10k to VCC_HOST (3V) to VCC_HOST (3.6V) 2.0 0.8 10 VCC 1.35 2.4 0.4 VCC 1.3V VCC 1.19 V V V V V A 10log(VDEASSERT / VASSERT) (Note 4) MAX3747/MAX3747A (Notes 4, 8) MAX3747B (Notes 4, 8, 9) VTH = -1.3V (Notes 4, 10) VTH = -1.3V (Notes 4, 10) VTH = -0.68V (Notes 4, 10) VTH = -0.68V (Notes 4, 10) VTH = -0.114V (Notes 4, 10) VTH = -0.114V (Notes 4, 10) 36.0 22.0 1.25 2.3 2.5 4.1 6.2 29.0 44.8 53.7 86.0 40.0 5.9 9.3 31.0 57.0 63.6 115 SYMBOL CONDITIONS VIN = 4mVP-P (Note 4) MIN TYP 120 6.4 MAX 150 UNITS VRMS kHz dB s mVP-P mVP-P mVP-P mVP-P mVP-P mVP-P
MAX3747/MAX3747A/MAX3747B
The data-input transition time is controlled by a 4th-order Bessel filter with f-3dB = 0.75 x 2.667GHz for all data rates of 2.667Gbps and below. The f-3db = 0.75 x 3.2GHz for a data rate of 3.2Gbps. Note 2: Supply current is measured with unterminated outputs or with AC-coupled output termination (see Figure 1). Note 3: Between sensitivity and overload, all AC specifications are met and the output is 0.95 x limited output amplitude. Note 4: Guaranteed by design and characterization. Note 5: The deterministic jitter (DJ) caused by the input filter is not included in the DJ generation specification. Note 6: The PRBS 223 - 1 equivalent pattern consists of a K28.5 pattern plus 240 ones plus K28.5 pattern plus 240 zeros. Note 7: Random jitter was measured without using a filter at the input. Note 8: The signal at the input is switched between two amplitudes, Signal_ON and Signal_OFF, as shown in Figure 2A. Note 9: The signal at the input is switched between 1.2VP-P and Signal_OFF as shown in Figure 2B. Note 10: VTH is the voltage at pin 5 referenced to VCC (see Figure 5). Note 1:
_______________________________________________________________________________________
3
155Mbps to 3.2Gbps, Low-Power SFP Limiting Amplifiers MAX3747/MAX3747A/MAX3747B
VCC ICC (SUPPLY CURRENT) IOUT (CML OUTPUT CURRENT)
50
50
MAX3747 MAX3747A MAX3747B
Figure 1. Power-Supply Current Measurement
VIN
VIN SIGNAL_ON = 1.2VP-P (OVERLOAD) SIGNAL_ON 1dB MAXIMUM DEASSERT LEVEL FOR A GIVEN VTH MAXIMUM DEASSERT LEVEL FOR A GIVEN RTH1/RTH2 RATIO
6dB
MAXIMUM POWER-DETECT WINDOW MINIMUM ASSERT LEVEL FOR A GIVEN VTH
6dB
MAXIMUM POWER-DETECT WINDOW MINIMUM ASSERT LEVEL FOR A GIVEN RTH1/RTH2 RATIO
0V
SIGNAL_OFF
TIME
0V
SIGNAL_OFF
TIME
Figure 2A. LOS Deassert Threshold--Set 1dB Below Receiver Sensitivity
Figure 2B. LOS Deassert Threshold--Operating at Input Overload
4
_______________________________________________________________________________________
155Mbps to 3.2Gbps, Low-Power SFP Limiting Amplifiers
Typical Operating Characteristics
(VCC = +3.3V, TA = +25C, unless otherwise noted.)
OUTPUT EYE DIAGRAM (MINIMUM INPUT)
MAX3747/MAX3747A/MAX3747B toc01
MAX3747/MAX3747A/MAX3747B
OUTPUT EYE DIAGRAM (MAXIMUM INPUT)
MAX3747/MAX3747A/MAX3747B toc02
OUTPUT EYE DIAGRAM (MINIMUM INPUT)
MAX3747/MAX3747A/MAX3747B toc03
3.2Gbps, 223 - 1 PRBS, 4mVP-P
3.2Gbps, 223 - 1 PRBS, 1200mVP-P
2.7Gbps, 223 - 1 PRBS, 4mVP-P
60mV/div
60mV/div
60mV/div
50ps/div
50ps/div
70ps/div
OUTPUT EYE DIAGRAM (MAXIMUM INPUT)
MAX3747/MAX3747A/MAX3747B toc04
OUTPUT EYE DIAGRAM AT +100C
MAX3747/MAX3747A/MAX3747B toc05
SUPPLY CURRENT vs. TEMPERATURE (EXCLUDES OUTPUT CURRENT)
45 SUPPLY CURRENT (mA) 40 35 30 25 20 15 10
MAX3747/MAX3747A/MAX3747B toc06
2.7Gbps, 223 - 1 PRBS, 1200mVP-P
2.125Gbps, CJTPAT, 50mVP-P
50
60mV/div
60mV/div
70ps/div
80ps/div
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 TEMPERATURE (C)
TRANSFER FUNCTION (OUTPUT VOLTAGE vs. INPUT VOLTAGE)
MAX3747/MAX3747A/MAX3747B toc07
RANDOM JITTER vs. TEMPERATURE
MAX3747/MAX3747A/MAX3747B toc08
RANDOM JITTER vs. INPUT AMPLITUDE
3.2Gbps
MAX3747/MAX3747A/MAX3747B toc09
1000 900 DIFFERENTIAL OUTPUT (mVP-P) 800 700 600 500 400 300 200 100 0 0 1 2 3 4 5 DIFFERENTIAL INPUT (mVP-P) MAX3747 MAX3747AMAX3747B
3.0 2.7 2.4 RANDOM JITTER (psRMS) 2.1 1.8 1.5 1.2 0.9 0.6 0.3 0
VIN = 50mVP-P, FREQ = 2.7Gbps
5
4 RANDOM JITTER (psRMS)
3
2
1
0 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 TEMPERATURE (C) 1 10 100 1000 10,000 DIFFERENTIAL INPUT AMPLITUDE (mVP-P)
_______________________________________________________________________________________
5
155Mbps to 3.2Gbps, Low-Power SFP Limiting Amplifiers MAX3747/MAX3747A/MAX3747B
Typical Operating Characteristics (continued)
(VCC = +3.3V, TA = +25C, unless otherwise noted.)
DETERMINISTIC JITTER vs. INPUT AMPLITUDE
MAX3747/MAX3747A/MAX3747B toc10 MAX3747/MAX3747A/MAX3747B toc11
BIT-ERROR RATIO vs. INPUT VOLTAGE
25 13,000 12,000 11,000 10,000 9000 8000 7000 6000 5000 4000 3000 2000 1000 1 0 1 MAXIM MAX3747
DETERMINISTIC JITTER vs. TEMPERATURE
35 DETERMINISTIC JITTER (ps) 30 25 20 15 10 5 VIN = 500mVP-P VIN = 5mVP-P FREQ = 3.2Gbps PATTERN = K28.5
MAX3747/MAX3747A/MAX3747B toc12
40
3.2Gbps, K28.5 PATTERN DETERMINISTIC JITTER (psP-P) 20
BIT-ERROR RATIO (10-12)
15
10
MICREL SY88993V
5
0 2 3 4 5 6 7 8 9 10 1 10 100 1000 10,000 DIFFERENTIAL INPUT AMPLITUDE (mVP-P) DIFFERENTIAL INPUT AMPLITUDE (mVP-P)
0 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 TEMPERATURE (C)
LOS ASSERT/DEASSERT TIMES vs. INPUT AMPLITUDE (LOW RTH1/RTH2 SETTINGS)
MAX3747/MAX3747A/MAX3747B toc13
LOS ASSERT/DEASSERT TIMES vs. INPUT AMPLITUDE (HIGH RTH1/RTH2 SETTINGS)
MAX3747/MAX3747A/MAX3747B toc14
ASSERT/DEASSERT vs. VTH
VTH (V) = VOLTAGE AT PIN 5 (V) WITH RESPECT TO VCC
MAX3747/MAX3747A/MAX3747B toc15
40 MAX3747B LOS ASSERT/DEASSERT TIME (s) 35 30 25 LOS ASSERT 20 15 LOS DEASSERT 10 5 0 0 200 400 600 800
40 MAX3747B LOS ASSERT/DEASSERT TIME (s) 35 30 25 20 15 LOS ASSERT 10 5 0 LOS DEASSERT
120 110 ASSERT/DEASSERT (mVP-P) 100 90 80 70 60 50 40 30 20 10 0
DEASSERT
ASSERT
1000 1200 1400
0
200
400
600
800
1000 1200 1400
-1.4
-1.2
-1.0
-0.8
-0.6
-0.4
-0.2
0
INPUT AMPLITUDE (mVP-P)
INPUT AMPLITUDE (mVP-P)
VTH (V)
ASSERT/DEASSERT vs. TEMPERATURE
MAX3747/MAX3747A/MAX3747B toc16
OUTPUT RETURN vs. FREQUENCY (SDD22) (INPUT SIGNAL LEVEL = -60dBm)
MAX3747/MAX3747A/MAX3747B toc17
INPUT RETURN vs. FREQUENCY (SDD11) (INPUT SIGNAL LEVEL = -60dBm)
MAX3747/MAX3747A/MAX3747B toc18
40 35 ASSERT/DEASSERT (mV) 30 25 20 15 10 5
VTH = -1.1V, FREQ = 2.7Gbps PATTERN = PRBS 223 - 1
30 20 10 SDD22 (dB) 0 -10
30 20 10 SDD11 (dB) 0 -10 -20 -30
DEASSERT
ASSERT
-20 -30
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 TEMPERATURE (C)
100
1000 FREQUENCY (MHz)
10,000
100
1000 FREQUENCY (MHz)
10,000
6
_______________________________________________________________________________________
155Mbps to 3.2Gbps, Low-Power SFP Limiting Amplifiers
Pin Description
PIN MAX3747/ MAX3747A/ MAX3747B NAME MICREL SY8893V NAME EN Disable Function Pin. The data outputs are held static when this pin is asserted high, transistor-to-transistor logic (TTL). The data outputs are enabled when this pin is held low. LOS functions remain active when outputs are disabled. For normal operation connect to GND. Noninverted Input Signal Inverted Input Signal Reference Voltage for LOS Threshold Setting Loss-of-Signal Level Set. A voltage on this pin created by a two-resistor divider sets the threshold level. Connect one resistor from this pin to VCC and another from this pin to VREF (see Figure 5). Ground Loss of Signal. Open collector for the MAX3747 and MAX3747A; internal 100k pullup to VCC for the MAX3747B. LOS is high when the level of the input signal drops below the preset threshold set by the TH input. LOS is deasserted low when the signal level is above the threshold. Inverted Data Output, CML Noninverted Data Output, CML Positive Power Supply FUNCTION
MAX3747/MAX3747A/MAX3747B
1
DISABLE
2 3 4 5 6
IN+ INVREF TH GND
DIN DIN VREF LOSLVL GND
7
LOS
LOS
8 9 10
OUTOUT+ VCC
DOUT DOUT VCC
Detailed Description
The limiting amplifiers consist of a multistage amplifier, offset-correction circuitry, an output buffer, and loss-ofsignal detect circuitry (see the Functional Diagram).
VCC
Input Stage
The input stage is shown in Figure 3. It provides 50 termination to VREF for each input signal, IN+ and IN-. The MAX3747/MAX3747A/MAX3747B should be AC-coupled.
MAX3747 MAX3747A MAX3747B
Multistage Amplifier
The high-bandwidth multistage amplifier provides approximately 57dB of gain for the MAX3747 and 61dB of gain for the MAX3747A/MAX3747B.
ESD STRUCTURES
Offset Correction Loop
The MAX3747/MAX3747A/MAX3747B are susceptible to DC offsets in the signal path because they have high gain. In communication systems using NRZ data with a 50% duty cycle, pulse-width distortion present in the signal or generated in the transimpedance amplifier appears as an input offset and is reduced by the offset correction loop. The offset correction loop sets a low-frequency cutoff of 3.2kHz.
50
50 VREF
Figure 3. Differential Input Stage
_______________________________________________________________________________________
7
155Mbps to 3.2Gbps, Low-Power SFP Limiting Amplifiers MAX3747/MAX3747A/MAX3747B
Functional Diagram
VCC
DIGITAL OFFSET CORRECTION IN+
MAX3747 MAX3747A MAX3747B
50
50 OUT+ OUT-
IN-
50
50 VREF VREF VREF RTH1 SIGNAL DETECT TH LOS
DISABLE
RTH2
RTH1 + RTH2 5k
VCC
CML Output Buffer
The CML outputs of the MAX3747/MAX3747A/ MAX3747B limiting amplifiers provide high tolerance to impedance mismatches and inductive connectors. The output current is approximately 10mA for the MAX3747 and 16mA for the MAX3747A/MAX3747B. Connecting the DISABLE pin to VCC disables the output. If the LOS pin is connected to the DISABLE pin, the outputs OUT+ and OUT- are at a static voltage (squelch) whenever the input signal level drops below the LOS threshold. The output buffer can be AC- or DC-coupled to the load (Figure 4). The MAX3747 output is 500mVP-P and the MAX3747A/ MAX3747B output is 800mVP-P.
VCC
50
50 OUT+ OUT-
DISABLE
Q3
Q4
Q1
Q2 ESD STRUCTURES
DATA DISABLE DISABLE
Figure 4. CML Output Buffer
8
_______________________________________________________________________________________
155Mbps to 3.2Gbps, Low-Power SFP Limiting Amplifiers MAX3747/MAX3747A/MAX3747B
Loss-of-Signal Indicator
The MAX3747/MAX3747A/MAX3747B are equipped with LOS circuitry that indicates when the input signal is below a programmable threshold, set by a voltage on the TH pin (see the Typical Operating Characteristics). The voltage on the TH pin is set by two resistors, one connecting from the TH pin to VCC and the other connecting from TH to VREF (Figure 5). An RMS power detector compares the input signal amplitude with this threshold and feeds the signal-detect information to the LOS output, which is open collector. To prevent LOS chatter in the region of the programmed threshold, approximately 2dB of hysteresis is built into the LOS assert/deassert function. Once asserted, LOS is not deasserted until the input amplitude rises to the required level. Figure 6 shows the LOS output circuit.
VCC RTH2 TH RTH1 VREF
Applications Information
Program the LOS Assert Threshold
Program the LOS assert threshold according to Figure 5. The combination of R TH1 and R TH2 should be greater than or equal to 5k, see the Assert/Deassert vs. VTH graph in the Typical Operating Characteristics.
Select the Coupling Capacitor
When AC-coupling is desired, coupling capacitors CIN and COUT should be selected to minimize the receiver's deterministic jitter. Jitter is decreased as the input low-frequency cutoff (fIN) is decreased: fIN = 1 / [2(50)(CIN)] For all applications, the recommended value for CIN and COUT is 0.1F, which provides fIN equal to 32kHz. Refer to Application Note HFAN-1.1: Choosing AC-Coupling Capacitors on the Maxim website (www.maxim-ic.com).
VTH = (RTH2 x (VREF - VCC)) / (RTH1 + RTH2) VTH IS VCC REFERENCED RTH1 + RTH2 5k
Figure 5. MAX3747/MAX3747A/MAX3747B LOS Threshold Circuit
VCC
*
LOS
ESD STRUCTURE
*100k PULLUP (MAX3747B ONLY)
Figure 6. MAX3747/MAX3747A/MAX3747B LOS Output Circuit
_______________________________________________________________________________________
9
155Mbps to 3.2Gbps, Low-Power SFP Limiting Amplifiers MAX3747/MAX3747A/MAX3747B
Chip Information
TRANSISTOR COUNT: 447 PROCESS: SiGe Bipolar
TOP VIEW
Pin Configuration
Package Information
For the latest package outline information, go to www.maxim-ic.com/packages.
PACKAGE TYPE 10 MAX DOCUMENT NO. 21-0061
DISABLE 1 IN+ INVREF TH 2 3 4 5
10 VCC 9 OUT+ OUTLOS GND
MAX3747 MAX3747A MAX3747B
8 7 6
MAX
Revision History
Pages changed at Rev 1: 1 to 10 (added MAX3747B)
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.
10 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 (c) 2007 Maxim Integrated Products
SPRINGER
is a registered trademark of Maxim Integrated Products.

▲Up To Search▲

Price & Availability of MAX374707

	To Download MAX374707 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .