MAX127ACAI+T ,Multirange, +5V, 12-Bit DAS with 2-Wire Serial InterfaceElectrical Characteristics(V = +5V ±5%; unipolar/bipolar range; external reference mode, V = 4.096V ..
MAX127ACAI-T ,Multirange, +5V, 12-Bit DAS with 2-Wire Serial Interfacefeatures include a 5MHz band-● Two Power-Down Modeswidth track/hold, an 8ksps throughput rate, and ..
MAX127ACNG+ ,Multirange, +5V, 12-Bit DAS with 2-Wire Serial InterfaceEVALUATION KIT AVAILABLEMAX127/MAX128 Multirange, +5V, 12-Bit DAS with 2-Wire Serial Interface
MAX127AEAI+ ,Multirange, +5V, 12-Bit DAS with 2-Wire Serial InterfaceFeaturesThe MAX127/MAX128 are multirange, 12-bit data acquisi- ● 12-Bit Resolution, 1/2 LSB Lineari ..
MAX127AENG ,Multirange, +5V, 12-Bit DAS with 2-Wire Serial Interface
MAX127AENG+ ,Multirange, +5V, 12-Bit DAS with 2-Wire Serial InterfaceApplicationsANALOG CH3MAX127● Industrial Control SystemsINPUTS CH4MAX128CH5● Data-Acquisition Syste ..
MAX3768CUB ,+3.0 V to +5.5 V, 1.25 Gbp/2.5Gbp limiting amplifierApplications†MAX3265EUE -40°C to +85°C 16 TSSOP-EP†Gigabit Ethernet Optical ReceiversMAX3268CUB 0°C ..
MAX3768CUB+T ,+3.0V to +5.5V, 1.25Gbps/2.5Gbps Limiting Amplifiersfeatures include RMS power detectors withprogrammable loss-of-signal (LOS) indication, an ♦ Program ..
MAX3770CEE ,2.125Gbps/1.063Gbps / 3.3V Fibre Channel RepeatersFeaturesThe MAX3770 is a 2.125Gbps Fibre Channel repeater Meet Fibre Channel Jitter Tolerance Requ ..
MAX3772CEE ,Dual-Rate Fibre Channel RepeatersMAX3772–MAX377519-2192; Rev 0; 10/01Dual-Rate Fibre Channel Repeaters
MAX3773CEE ,Dual-Rate Fibre Channel RepeatersELECTRICAL CHARACTERISTICS(V = +3.0V to +3.6V, 8B/10B data coding, C = 0.047µF, lock pin loaded wit ..
MAX3773CEE+ ,Dual-Rate Fibre Channel RepeatersFeaturesThe MAX3772–MAX3775 are dual-rate (1.0625Gbps Pin Selectable 1.0625Gbps/2.125Gbps Dual-Rat ..
MAX127ACAI+T-MAX127ACAI-T-MAX127ACNG+-MAX127AEAI+-MAX127AENG+-MAX127BCAI+-MAX127BCNG+-MAX127BEAI+-MAX127BENG+-MAX128BCNG+
Multirange, +5V, 12-Bit DAS with 2-Wire Serial Interface
General DescriptionThe MAX127/MAX128 are multirange, 12-bit data acquisi-
tion systems (DAS) that require only a single +5V supply
for operation, yet accept signals at their analog inputs
that may span above the power-supply rail and below
ground. These systems provide eight analog input chan-
nels that are independently software programmable for
a variety of ranges: ±10V, ±5V, 0 to +10V, 0 to +5V for
the MAX127; and ±VREF, ±VREF/2, 0 to +VREF, 0 to
+VREF/2 for the MAX128. This range switching increases
the effective dynamic range to 14 bits and provides the
flexibility to interface 4–20mA, ±12V, and ±15V-powered
sensors directly to a single +5V system. In addition, these
converters are fault protected to ±16.5V; a fault condition
on any channel will not affect the conversion result of the
selected channel. Other features include a 5MHz band-
width track/hold, an 8ksps throughput rate, and the option
of an internal 4.096V or external reference.
The MAX127/MAX128 feature a 2-wire, I2C-compatible
serial interface that allows communication among multiple
devices using SDA and SCL lines.
A hardware shutdown input (SHDN) and two softwarepro-
grammable power-down modes (standby and full power-
down) are provided for low-current shutdown between
conversions. In standby mode, the reference buffer
remains active, eliminating startup delays.
The MAX127/MAX128 are available in 24-pin narrow
PDIP or space-saving 28-pin SSOP packages.
Applications●Industrial Control Systems●Data-Acquisition Systems●Robotics●Automatic Testing●Battery-Powered Instruments●Medical Instruments
Features●12-Bit Resolution, 1/2 LSB Linearity●+5V Single-Supply Operation●I2C-Compatible, 2-Wire Serial Interface●Four Software-Selectable Input RangesMAX127: 0 to +10V, 0 to +5V, ±10V, ±5VMAX128: 0 to +VREF, 0 to +VREF/2, ±VREF,
±VREF/2●8 Analog Input Channels●8ksps Sampling Rate●±16.5V Overvoltage-Tolerant Input Multiplexer●Internal 4.096V or External Reference●Two Power-Down Modes●24-Pin Narrow PDIP or 28-Pin SSOP Packages
Pin Configurations appear at end of data sheet.
Ordering Information continued at end of data sheet.+Denotes a lead(Pb)-free/RoHS-compliant package.
PARTTEMP RANGEPIN-PACKAGEINL
(LSB)
MAX127ACNG+0°C to +70°C24 Narrow PDIP±1/2
MAX127ACNG+0°C to +70°C24 Narrow PDIP±1
VDD
CH0
CH1
CH2
CH3
CH4
CH5
CH6
CH7
DGND
4.7µF
0.1µF
1kΩ
SHDN
+5V
SCL
SDA
REF
REFADJ
AGND
SCLSDA
MAX127
MAX128ANALOG
INPUTS
0.01µF
MAX127/MAX128Multirange, +5V, 12-Bit DAS with
2-Wire Serial Interface
Typical Operating Circuit
Ordering Information
EVALUATION KIT AVAILABLE
VDD to AGND ..........................................................-0.3V to +6V
AGND to DGND ...................................................-0.3V to +0.3V
CH0–CH7 to AGND ..........................................................±16.5V
REF to AGND ...........................................-0.3V to (VDD + 0.3V)
REFADJ to AGND ....................................-0.3V to (VDD + 0.3V)
A0, A1, A2 to DGND .................................-0.3V to (VDD + 0.3V)
SHDN, SCL, SDA to DGND ....................................-0.3V to +6V
Max Current into Any Pin ...................................................50mA
Continuous Power Dissipation (TA = +70°C)24-Pin Narrow PDIP
(derate 13.33mW/°C above +70°C) ..........................1067mW28-Pin SSOP (derate 15mW/°C above +70°C) .........1201mW
Operating Temperature RangesMAX127_ C_ _/MAX128_ C_ _..........................0°C to +70°CMAX127_ E_ _/MAX128_ E_ _ ......................-40°C to +85°C
Storage Temperature Range ............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Soldering Temperature (reflow) .......................................+260°C
(VDD = +5V ±5%; unipolar/bipolar range; external reference mode, VREF = 4.096V; 4.7μF at REF; external clock, fCLK = 400kHz;
TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
ACCURACY (Note 1)Resolution12Bits
Integral NonlinearityINLMAX127A±1/2LSBMAX127B/MAX128B±1
Differential NonlinearityDNL±1LSB
Offset Error
UnipolarMAX127A±3
LSBMAX127B/MAX128B±5
BipolarMAX127A±5
MAX127B/MAX128B±10
Channel-to-Channel Offset Error
Matching
Unipolar±0.1LSBBipolar±0.3
Gain Error (Note 2)
UnipolarMAX127A±7
LSBMAX127B/MAX128B±10
BipolarMAX127A±7
MAX127B/MAX128B±10
Gain Tempco (Note 2)Unipolar3ppm/°CBipolar5
DYNAMIC SPECIFICATIONS (800Hz sine-wave input, ±10VP-P (MAX127) or ±4.096VP-P (MAX128), fSAMPLE = 8ksps)Signal-to-Noise Plus Distortion
RatioSINAD70dB
Total Harmonic DistortionTHDUp to the 5th harmonic-87-80dB
Spurious-Free Dynamic RangeSFDR81dB
Channel-to-Channel Crosstalk4kHz, VIN = ±5V (Note 3)-86dBDC, VIN = ±16.5V-96
Aperture Delay200ns
MAX127/MAX128Multirange, +5V, 12-Bit DAS with
2-Wire Serial Interface
Absolute Maximum RatingsStresses 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
(VDD = +5V ±5%; unipolar/bipolar range; external reference mode, VREF = 4.096V; 4.7μF at REF; external clock, fCLK = 400kHz;
TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
ANALOG INPUTTrack/Hold Acquisition Time3µs
Small-Signal Bandwidth-3dB
rolloff
±10V or ±VREF range5
MHz
±5V or ±VREF/2 range2.5
0 to 10V or 0 to VREF range2.5
0 to 5V or 0 to VREF/2 range1.25
Input Voltage RangeVIN
Unipolar,
Table 3
MAX1270105
MAX128VREFVREF/2
Bipolar,
Table 3
MAX127-10+10+5
MAX128-VREFVREF
-VREF/2VREF/2
Input CurrentIIN
UnipolarMAX1270 to 10V range-10+720
0 to 5V range-10+360
MAX128-10+0.1+10
Bipolar
MAX127±10V range-1200+720
±5V range-600+360
MAX128±VREF range-1200+10
±VREF/2 range-600+10
Input ResistanceΔVIN/ΔIIN
Unipolar21kΩ
Bipolar16
Input Capacitance(Note 4)40pF
INTERNAL REFERENCEREFOUT VoltageVREFTA = +25°C4.0764.0964.116V
REFOUT TempcoTC VREFMAX127_C/MAX128_C±15ppm/°CMAX127_E/MAX128_E±30
Output Short-Circuit Current30mA
Load Regulation (Note 5)0 to 0.5mA output current10mV
Capacitive Bypass at REF4.7μF
REFADJ Output Voltage2.4652.5002.535V
REFADJ Adjustment RangeFigure 12±1.5%
Buffer Voltage Gain1.638V/V
MAX127/MAX128Multirange, +5V, 12-Bit DAS with
2-Wire Serial Interface
Electrical Characteristics (continued)
(VDD = +5V ±5%; unipolar/bipolar range; external reference mode, VREF = 4.096V; 4.7μF at REF; external clock, fCLK = 400kHz;
TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
REFERENCE INPUT (buffer disabled, reference input applied to REF)Input Voltage Range2.44.18V
Input CurrentVREF = 4.18V
Normal, or STANDBY
power-down mode400μA
FULL power-down mode1
Input ResistanceNormal or STANDBY power-down mode10kΩ
FULL power-down mode5MΩ
REFADJ Threshold for
Buffer DisableVDD - 0.5V
POWER REQUIREMENTSSupply VoltageVDD4.755.25V
Supply CurrentIDD
Normal mode, bipolar ranges18Normal mode, unipolar ranges610
STANDBY power-down mode (Note 6)700850µA
FULL power-down mode120220
Power-Supply Rejection Ratio
(Note 7)PSRRExternal reference = 4.096V±0.1±0.5LSBInternal reference±0.5
TIMINGExternal Clock Frequency RangefCLK0.4MHz
Conversion TimetCONV6.07.710.0µs
Throughput Rate8ksps
Bandgap Reference
Startup TimePower-up (Note 8)200μs
Reference Buffer Settling TimeTo 0.1mV, REF bypass
capacitor fully discharged
CREF = 4.7μF8CREF = 33μF60
DIGITAL INPUTS (SHDN, A2, A1, A0)Input High Threshold VoltageVIH2.4V
Input Low Threshold VoltageVIL0.8V
Input Leakage CurrentIINVIN = 0V or VDD±0.1±10µA
Input CapacitanceCIN(Note 4)15pF
Input HysteresisVHYS0.2V
MAX127/MAX128Multirange, +5V, 12-Bit DAS with
2-Wire Serial Interface
Electrical Characteristics (continued)
(VDD = +5V ±5%; unipolar/bipolar range; external reference mode, VREF = 4.096V; 4.7μF at REF; external clock, fCLK = 400kHz;
TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.)
(VDD = +4.75V to +5.25V; unipolar/bipolar range; external reference mode, VREF = 4.096V; 4.7μF at REF pin; TA = TMIN to TMAX,
unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
DIGITAL INPUTS (SDA, SCL)Input High Threshold VoltageVIH0.7 x VDDV
Input Low Threshold VoltageVIL0.3 x VDDV
Input HysteresisVHYS0.05 x VDDV
Input Leakage CurrentIINVIN = 0V or VDD±0.1±10µA
Input CapacitanceCIN(Note 4)15pF
DIGITAL OUTPUTS (SDA)Output Low VoltageVOLISINK = 3mA0.4VISINK = 6mA0.6
Three-State Output CapacitanceCOUT(Note 4)15pF
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
2-WIRE FAST MODESCL Clock FrequencyfSCL400kHz
Bus Free Time Between a
STOP and START ConditiontBUF1.3µs
Hold Time (Repeated)
START ConditiontHD,STA0.6µs
Low Period of the SCL ClocktLOW1.3µs
High Period of the SCL ClocktHIGH0.6µs
Setup Time for a Repeated
START ConditiontSU,STA0.6µs
Data Hold TimetHD,DAT00.9µs
Data Setup TimetSU,DAT100ns
Rise Time for Both SDA and SCL
Signals (Receiving)tRCb = Total capacitance of one bus line in pF20 +
0.1 x Cb300ns
Fall Time for Both SDA and SCL
Signals (Receiving)tFCb = Total capacitance of one bus line in pF20 +
0.1 x Cb300ns
Fall Time for Both SDA and SCL
Signals (Transmitting)tFCb = Total capacitance of one bus line in pF20 +
0.1 x Cb250ns
Set-Up Time for STOP ConditiontSU,STO0.6µs
Capacitive Load for Each
Bus LineCb400pF
MAX127/MAX128Multirange, +5V, 12-Bit DAS with
2-Wire Serial Interface
Electrical Characteristics (continued)
Timing Characteristics
Note 1: Accuracy specifications tested at VDD = 5.0V. Performance at power-supply tolerance limits is guaranteed by Power-Supply
Rejection test.
Note 2: External reference: VREF = 4.096V, offset error nulled, ideal last-code transition = FS - 3/2 LSB.
Note 3: Ground “on” channel, sine wave applied to all “off” channels.
Note 4: Guaranteed by design. Not tested.
Note 5: Use static external load during conversion for specified accuracy.
Note 6: Tested using internal reference.
Note 7: PSRR measured at full scale. Tested for the ±10V (MAX127) and ±4.096V (MAX128) input ranges.
Note 8: Not subject to production testing. Provided for design guidance only.
(VDD = +4.75V to +5.25V; unipolar/bipolar range; external reference mode, VREF = 4.096V; 4.7μF at REF pin; TA = TMIN to TMAX,
unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
2-WIRE STANDARD MODESCL Clock FrequencyfSCL100kHz
Bus Free Time Between a STOP
and START ConditiontBUF4.7µs
Hold Time (Repeated) START
ConditiontHD,STA4.0µs
Low Period of the SCL ClocktLOW4.7µs
High Period of the SCL ClocktHIGH4.0µs
Setup Time for a Repeated
START ConditiontSU, STA4.7µs
Data Hold TimetHD, DAT00.9µs
Data Setup TimetSU, DAT250ns
Rise Time for Both SDA and SCL
Signals (Receiving)tR1000ns
Fall Time for Both SDA and SCL
Signals (Receiving)tF300ns
Fall Time for Both SDA and SCL
Signals (Transmitting)tFCb = total capacitance of one bus line in pF,
up to 6mA sink
20 +
0.1 x Cb250ns
Setup Time for STOP ConditiontSU, STO4.0µs
Capacitive Load for Each
Bus LineCb400pF
Pulse Width of Spike SuppressedtSP050ns
MAX127/MAX128Multirange, +5V, 12-Bit DAS with
2-Wire Serial Interface
Timing Characteristics (continued)
(VDD = +5V, external reference mode, VREF = 4.096V; 4.7μF at REF; external clock, fCLK = 400kHz; TA = +25°C, unless otherwise
noted.)2134567
SUPPLY CURRENT vs. SUPPLY VOLTAGEmax127/8-01
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (mA)
FULL POWER-DOWN SUPPLY CURRENT
vs. TEMPERATURE
MAX127/8-04
TEMPERATURE (°C)
FULL POWER-DOWN SUPPLY CURRENT (µA)
INTERNAL
REFERENCE
EXTERNAL
REFERENCE
CHANNEL-TO-CHANNEL GAIN-ERROR
MATCHING vs. TEMPERATURE
MAX127/8-07
CHANNEL-TO-CHANNEL GAIN-ERROR MATCHING (LSB)
BIPOLAR MODE
UNIPOLAR MODE
SUPPLY CURRENT vs. TEMPERATURE
MAX127/8-02
TEMPERATURE (°C)
SUPPLY CURRENT (mA)
NORMALIZED REFERENCE VOLTAGE
vs. TEMPERATURE
MAX127/8-05
TEMPERATURE (°C)
NORMALIZED REFERENCE VOLTAGE
INTEGRAL NONLINEARITY vs.
DIGITAL CODE
MAX127/8-08
INTEGRAL NONLINEARITY (LSB)
STANDBY SUPPLY CURRENT
vs. TEMPERATURE
MAX127/8-03
TEMPERATURE (°C)
STANDBY SUPPLY CURRENT (µA)
INTERNAL
REFERENCE
EXTERNAL
REFERENCE
CHANNEL-TO-CHANNEL OFFSET-ERROR
MATCHING vs. TEMPERATURE
MAX127/8-06
TEMPERATURE (°C)
CHANNEL-TO-CHANNEL OFFSET-ERROR MATCHING (LSB)
BIPOLAR MODE
UNIPOLAR MODE
FFT PLOT
MAX127/8-09
AMPLITUDE (dB)
VDD = 5V
fIN = 800Hz
fSAMPLE = 8kHz
MAX127/MAX128Multirange, +5V, 12-Bit DAS with
2-Wire Serial Interface
Typical Operating Characteristics
PIN
NAMEFUNCTION
NARROW PDIPSSOP1, 21, 2VDD+5V Supply. Bypass with a 0.1μF capacitor to AGND.
3, 9, 22, 244, 7, 8, 11, 22,
24, 25, 28N.C.No Connection. No internal connection.3DGNDDigital Ground5SCLSerial Clock Input
6, 8, 106, 10, 12A0, A2, A1Address Select Inputs9SDA
Open-Drain Serial Data I/O. Input data is clocked in on the rising edge of
SCL, and output data is clocked out on the falling edge of SCL.
External pullup resistor required.13SHDNShutdown Input. When low, device is in full power-down (FULLPD) mode.
Connect high for normal operation.14AGNDAnalog Ground
13–2015–21, 23CH0–CH7Analog Input Channels26REFADJ
Bandgap Voltage-Reference Output/External Adjust Pin. Bypass with
a 0.01µF capacitor to AGND. Connect to VDD when using an external
reference at REF.27REF
Reference Buffer Output/ADC Reference Input. In internal reference mode,
the reference buffer provides a 4.096V nominal output, externally adjustable
at REFADJ. In external reference mode, disable the internal reference by
pulling REFADJ to VDD and applying the external reference to REF.
MAX127/MAX128Multirange, +5V, 12-Bit DAS with
2-Wire Serial Interface
Pin Description
