MAX3800UHJ ,3.2Gbps Adaptive Equalizer and Cable DriverELECTRICAL CHARACTERISTICS(V = +3.14V to +3.46V, T = 0°C to +85°C. Typical values are at V = +3.3V ..
MAX3800UHJ+ ,3.2Gbps Adaptive Equalizer and Cable DriverELECTRICAL CHARACTERISTICS(V = +3.14V to +3.46V, T = 0°C to +85°C. Typical values are at V = +3.3V ..
MAX3800UTJ+T ,3.2Gbps Adaptive Equalizer and Cable DriverELECTRICAL CHARACTERISTICS(V = +3.14V to +3.46V, T = 0°C to +85°C. Typical values are at V = +3.3V ..
MAX3801UGG ,PLASTIC ENCAPSULATED DEVICESapplications. The equalizer includes differential CML data inputs and outputs, a loss-of-signal (LO ..
MAX3801UTG+ ,3.2Gbps Adaptive EqualizerELECTRICAL CHARACTERISTICS(V = +3.14V to +3.46V, T = 0°C to +85°C. Typical values are at V = +3.3V ..
MAX3801UTG+T ,3.2Gbps Adaptive EqualizerApplicationsTEMP PIN- PACKAGESDH/SONET Transmission EquipmentPARTRANGE PACKAGE CODEMAX3801UGG 0°C t ..
MAX738A ,5V, Step-Down, Current-Mode PWM DC-DC ConvertersApplicationsMAX730AC/D 0°C to +70°C Dice*Portable InstrumentsMAX730AEPA -40°C to +85°C 8 Plastic DI ..
MAX738ACPA ,5V, Step-Down, Current-Mode PWM DC-DC Converters
MAX738ACPA ,5V, Step-Down, Current-Mode PWM DC-DC Converters
MAX738ACPA+ ,5V, Step-Down, Current-Mode PWM DC-DC ConvertersMAX730A/MAX738A/MAX744A19-0165; Rev 2; 1/965V, Step-Dow n,Current-Mode PWM DC-DC Converters________ ..
MAX738AEPA ,5V / Step-Down / Current-Mode PWM DC-DC ConvertersELECTRICAL CHARACTERISTICS(Circuit of Figure 3, V+ = 9V for the MAX730A, V+ = 12V for the MAX738A/M ..
MAX738AEWE ,5V / Step-Down / Current-Mode PWM DC-DC ConvertersMAX730A/MAX738A/MAX744A19-0165; Rev 2; 1/965V, Step-Down,Current-Mode PWM DC-DC Converters_________ ..
MAX3800UHJ
3.2Gbps Adaptive Equalizer and Cable Driver
General DescriptionThe MAX3800 is a +3.3V adaptive cable equalizer and
cable driver implemented together on a single chip. It is
designed for coaxial and twin-axial cable point-to-point
communications applications. The driver features differ-
ential current-mode logic (CML) inputs and outputs as
well as adjustable output amplitude. The equalizer
includes differential CML data inputs and outputs, a
loss-of-signal (LOS) output, and a cable integrity moni-
tor (CIM) output.
The adaptive cable equalizer is capable of equalizing
differential or single-ended signals at data rates up to
3.2Gbps. It automatically adjusts to attenuation caused
by skin-effect losses of up to 30dB at 1.6GHz. The
equalizer effectively extends the usable length of cop-
per cable in high-frequency interconnect applications.
The MAX3800 is available in a 32-pin TQFP package
with exposed pad and consumes only 200mW at
+3.3V. The driver can be disconnected from the power
supply when it is not needed, resulting in a 40% reduc-
tion in supply current.
ApplicationsHigh-Speed Links in Communications
and Data Systems
Backplane and Interconnect Applications
SDH/SONET Transmission Equipment
FeaturesSingle +3.3V OperationTypical Power Dissipation = 200mW at +3.3VData Rates Up to 3.2GbpsAdjustable Cable Driver Output AmplitudeEqualizer Automatically Adjusts for Different
Cable Lengths0dB to 30dB Equalization at 1.6GHz (3.2Gbps)Loss-of-Signal (LOS) IndicatorCable Integrity Monitor (CIM)On-Chip Input and Output TerminationsLow External Component CountOperating Temperature Range = 0°C to +85°CESD Protection on Cable Inputs and Outputs
MAX3800
3.2Gbps Adaptive Equalizer
and Cable Driver
Ordering Information
Typical Application Circuit19-1953; Rev 1; 11/01
Pin Configuration appears at end of data sheet.
MAX3800
3.2Gbps Adaptive Equalizer
and Cable Driver
ABSOLUTE MAXIMUM RATINGS
DC ELECTRICAL CHARACTERISTICSStresses 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.
Supply Voltage, VCC..............................................-0.5V to +6.0V
Voltage at LOS, RMOD, and CIM...............-0.5V to (VCC+ 0.5V)
Voltage at EIN+, EIN-, DIN+, DIN-.....(VCC- 1V) to (VCC+ 0.5V)
Current Out of EOUT+, EOUT-, DOUT+, DOUT-................25mA
Continuous Power Dissipation (TA= +85°C)
32-Pin TQFP-EP (derate 22.2mW/°C above +85°C)...1444mW
Operating Ambient Temperature Range................0°C to +85°C
Storage Temperature Range.............................-55°C to +150°C
Lead Temperature (soldering, 10s).................................+300°C
MAX3800
3.2Gbps Adaptive Equalizer
and Cable Driver
Note 1:Equalizer and driver total currents (equalizer with maximum equalization and driver with maximum output swing).
Note 2:Input voltage within specification limits, 50Ωto VCCat each output.
Note 3:Minimum cable input for LOSto assert high.
Note 4:100kΩload to ground.
Note 5:AC electrical characteristics are guaranteed by design and characterization.
Note 6:VDIN= 400mVp-p to 1100mVp-p (differential), 10kΩ≤RMOD ≤20kΩ, 3.2Gbps 213-1 PRBS with 100 consecutive ones and
100 consecutive zeros substituted.
Note 7:Includes random jitter and deterministic jitter.
Note 8:Differential cable input voltage = 700mVp-p, 3.2Gbps 213-1 PRBS with 100 consecutive ones and 100 consecutive zeros
substituted. Cable loss is due to skin effect only.
AC ELECTRICAL CHARACTERISTICS(VCC= +3.14V to +3.46V, TA= 0°C to +85°C. Typical values are at VCC= +3.3V and TA= +25°C, unless otherwise noted.) (Note 5)
MAX3800
3.2Gbps Adaptive Equalizer
and Cable DriverSUPPLY CURRENT vs. TEMPERATURE
MAX3800 toc01
TEMPERATURE (°C)
SUPPLY CURRENT (mA)
CABLE DRIVER OUTPUT VOLTAGE vs. RMOD
MAX3800 toc02
RMOD (kΩ)
DRIVER OUTPUT VOLTAGE (mV)
DRIVER INPUT RETURN LOSS (S11)
MAX3800 toc03
FREQUENCY (GHz)
GAIN (dB)
DRIVER OUTPUT RETURN LOSS (S22)
MAX3800 toc04
FREQUENCY (GHz)
GAIN (dB)
EQUALIZER RESIDUAL JITTER vs. POWER SUPPLY
NOISE (100mVp-p SINE WAVE) (40FT OF MADISON
#14887 SHIELDED TWISTED PAIR-DIFFERENTIAL)
MAX3800 toc05
NOISE FREQUENCY (MHz)
JITTER (ps
p-p
110505545606570758085 (INCHES)
EQUALIZER RESIDUAL JITTER vs. LINE LENGTH
(FR-4 6MIL STRIPLINE - SINGLE-ENDED)MAX3800 toc09
LINE LENGTH
JITTER (ps
p-p
1.021.271.401.141.521.651.771.902.032.16 (METERS)
10020304050 (FEET)
EQUALIZER RESIDUAL JITTER vs.
CABLE LENGTH (MADISON #13887 SHIELDED
TWISTED PAIR-DIFFERENTIAL)MAX3800 toc07
CABLE LENGTH
JITTER (ps
p-p
3.056.19.1412.1915.24 (METERS)
16055653545758595 (FEET)
EQUALIZER RESIDUAL JITTER vs.
CABLE LENGTH (RG179B 75Ω COAXIAL
CABLE - SINGLE-ENDED)MAX3800 toc08
CABLE LENGTH
JITTER (ps
p-p
7.6516.7619.8110.6713.7222.8625.9128.96 (METERS)
EQUALIZER RESIDUAL JITTER vs. CABLE
INPUT AMPLITUDE (RG179B 75Ω
COAXIAL CABLE - SINGLE-ENDED)
MAX3800 toc06
CABLE INPUT AMPLITUDE (mV)
JITTER (ps
p-p
Typical Operating Characteristics(TA = +25°C, VCC= +3.3V, all jitter measurements done at 3.2Gbps, 700mV cable input with 213-1 PRBS pattern with 100 consecutive
ones and 100 consecutive zeros substituted. Note:Test pattern produces near worst-case jitter results. Results will vary with pattern,
unless otherwise noted.)
MAX3800
3.2Gbps Adaptive Equalizer
and Cable Driver
EQUALIZER INPUT AFTER
115FT OF CABLE (TOP)
EQUALIZER OUTPUT (BOTTOM)MAX3800 toc10
EQUALIZER OUTPUT EYE DIAGRAM
AFTER 115FT OF 50Ω GORE 89 CABLE
(DIFFERENTIAL, 27-1 PRBS)MAX3800 toc11
60ps/div (2.5Gbps)
EQUALIZER OUTPUT EYE DIAGRAM
AFTER 100FT OF 75Ω RG179 CABLE
(SINGLE-ENDED, 27-1 PRBS)MAX3800 toc12
68ps/div (2.5Gbps)
EQUALIZER OUTPUT EYE DIAGRAM
AFTER 100FT OF BELDEN 9207 CABLE
(DIFFERENTIAL, 27-1 PRBS)MAX3800 toc13
60ps/div (2.5Gbps)60ps/div (2.5Gbps)
EQUALIZER OUTPUT EYE DIAGRAM
AFTER 50FT OF MADISON #14887
SHIELDED TWISTED PAIR CABLE
(DIFFERENTIAL, 27-1 PRBS)MAX3800 toc14
CIM VOLTAGE vs. CABLE LENGTH
(RG179B 75Ω COAXIAL CABLE -
SINGLE-ENDED)
MAX3800 toc15
CABLE LENGTH (FEET)
CIM VOLTAGE (V)
EQUALIZER INPUT RETURN LOSS (S11)
MAX3800 toc16
FREQUENCY (GHz)
GAIN (dB)
EQUALIZER OUTPUT RETURN LOSS (S22)
MAX3800 toc17
FREQUENCY (GHz)
GAIN (dB)
Typical Operating Characteristics (continued)(TA = +25°C, VCC= +3.3V, all jitter measurements done at 3.2Gbps, 700mV cable input with 213-1 PRBS pattern with 100 consecutive
ones and 100 consecutive zeros substituted. Note:Test pattern produces near worst-case jitter results. Results will vary with pattern,
unless otherwise noted.)
Detailed DescriptionThe MAX3800 consists of a cable driver (transmitter)
and an adaptive cable equalizer (receiver). The driver
and equalizer are implemented on the same chip, but
they are completely independent.
The Cable DriverThe cable driver accepts differential or single-ended
current-mode logic (CML) input data at rates up to
3.2Gbps. The driver output is also implemented using
CML. The maximum output amplitude can be adjusted
over a typical range of 450mV to 870mV by changing
the value of the RMOD resistor between 10kΩand
20kΩ(this resistor is connected between the RMOD pin
and ground).
The Adaptive Cable EqualizerThe adaptive cable equalizer accepts differential CML
input data at rates up to 3.2Gbps and is capable of
equalizing differential or single-ended signals. It auto-
matically adjusts to attenuation levels of up to 30dB at
1.6GHz (due to skin-effect losses in copper cable). The
equalizer consists of a CML input buffer, a loss-of-sig-
nal detector, a flat response amplifier, a skin-effect
compensation amplifier, a current-steering network, a
dual power-detector feedback loop, an output limiting
amplifier, and a CML output buffer (Figure 1).
General Theory of OperationThe shape of the power spectrum of a random bit
stream can be described by the square of the sinc
function, where sinc f = (sin πf) / πf. For sufficiently long
bit patterns (nonrandom bit streams), sinc2(f) is a good
approximation. From the shape of the sinc2(f) function,
we can estimate the ratio of the power densities at any
two frequencies. The MAX3800 adaptive equalizer
employs this principle by incorporating a feedback loop
that continuously monitors the power at two frequencies
and dynamically adjusts the equalizer to maintain the
correct power ratio.
CML Input and Output BuffersThe input and output buffers are implemented using
current-mode logic (CML). Equivalent circuits are
shown in Figures 2 and 3. For details on interfacing with
MAX3800
3.2Gbps Adaptive Equalizer
and Cable Driver
MAX3800
3.2Gbps Adaptive Equalizer
and Cable Driver
