19-1902; Rev 1; 8/94High-Voltage, Fault-ProtectedAnalog Multiplexers_______________General DescriptionThe MAX378 8-channel single-ended (1-of-8) multiplexerand the MAX379 4-channel differential (2-of-8) multiplexeruse a series N-channel/P-channel/N-channel structure toprovide significant fault protection. If the power supplies tothe MAX378/MAX379 are inadvertently turned off whileinput voltages are still applied, allchannels in the muxesare turned off, and only a few nanoamperes of leakage cur-rent will flow into the inputs. This protects not only theMAX378/MAX379 and the circuitry they drive, but also thesensors or signal sources that drive the muxes.
The series N-channel/P-channel/N-channel protectionstructure has two significant advantages over the simplecurrent-limiting protection scheme of the industry’s first-generation fault-protected muxes. First, the Maxim protec-____________________________FeaturesoooooooooFault Input Voltage ±75V with Power Supplies OffFault Input Voltage ±60V with ±15V Power SuppliesAll Switches Off with Power Supplies Off
On Channel Turns OFF if Overvoltage Occurs onInput or Output
Only Nanoamperes of Input Current Under AllFault Conditions
No Increase in Supply Currents Due to FaultConditions
Latchup-Proof Construction
Operates from ±4.5V to ±18V Supplies
All Digital Inputs are TTL and CMOS CompatibleMAX378/MAX379tion scheme limits fault currents to nanoamp leakageo
Low-Power Monolithic CMOSDesign
values rather than many milliamperes. This prevents dam-age to sensors or other sensitive signal sources. Second,the MAX378/MAX379 fault-protected muxes can withstand______________Ordering Informationa continuous±60V input, unlike the first generation, whichhad a continuous ±35V input limitation imposed by powerPARTTEMP. RANGEPIN-PACKAGEdissipation considerations.
MAX378CPE0°C to +70°C16 Plastic DIPMAX378CWG0°C to +70°C24 Wide SOAll digital inputs have logic thresholds of 0.8V and 2.4V,ensuring both TTL and CMOS compatibility without requir-MAX378CJE0°C to +70°C16 CERDIPing pull-up resistors. Break-before-make operation isMAX378C/D0°C to +70°CDice**guaranteed. Power dissipation is less than 2mW.
MAX378EPE-40°C to +85°C16 Plastic DIPMAX378EWG-40°C to +85°C24 Wide SO________________________ApplicationsMAX378EJE-40°C to +85°C16 CERDIPData Acquisition Systems
MAX378MJE-55°C to +125°C16 CERDIPIndustrial and Process Control SystemsMAX378MLP-55°C to +125°C20 LCC*Avionics Test Equipment
Ordering Information continued at end of data sheet.Signal Routing Between Systems
* Contact factory for availability.**The substrate may be allowed to float or be tied to V+ (JI CMOS).__________________________________________________________Pin ConfigurationsTOP VIEWA0116A1A0116A1EN215A2EN215GNDV-314GNDV-314V+IN14MAX37813V+IN1A4MAX37913IN1BIN2512IN5IN2A512IN2BIN3611IN6IN3A611IN3BIN4710IN7IN4A710IN4BOUTIN8OUTAOUTBPin Configurations continued at end of data sheet.DIPDIP________________________________________________________________Maxim Integrated Products1
Call toll free 1-800-998-8800 for free samples or literature.元器件交易网www.cecb2b.com
High-Voltage, Fault-ProtectedAnalog MultiplexersMAX378/MAX379ABSOLUTE MAXIMUM RATINGS
Voltage between Supply Pins..............................................+44VV+ to Ground...................................................................+22VV- to Ground......................................................................-22VDigitalInput Overvoltage:
V+......................................................................+4VVEN, VA
V-........................................................................-4V
Analog Input with Multiplexer Power On..............................±65V
RecommendedV+.....................................+15VPower SuppliesV-.......................................-15V
Analog Input with Multiplexer Power Off..............................±80V
Continuous Current, IN or OUT...........................................20mAPeak Current, IN or OUT
(Pulsed at 1ms, 10% duty cycle max)............................40mAPower Dissipation (Note 1) (CERDIP)................................1.28WOperating Temperature Range:
MAX378/379C.....................................................0°C to +70°CMAX378/379E..................................................-40°C to +85°CMAX378/379M...............................................-55°C to +125°CStorage Temperature Range.............................-65°C to +150°CNote 1:Derate 12.8mW/°C above TA= +75°C
{
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Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functionaloperation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure toabsolute maximum rating conditions for extended periods may affect device reliability.ELECTRICAL CHARACTERISTICS
(V+ = +15V, V- = -15V; VAH(Logic Level High) = +2.4V, VAL(Logic Level Low) = +0.8V, unless otherwise noted.)
-55°C to +125°CMINTYPMAXSTATICON ResistanceOFF Input Leakage CurrentrDS(ON)IIN(OFF)VOUT= ±10V, IIN= 100µA VAL= 0.8V, VAH= 2.4V±VIN= ±10V, VOUT= 10VVEN= 0.8V (Note 6)±VOUT= ±10V, VIN= 10VVEN= 0.8VMAX378(Note 6)MAX379VIN(ALL)= VOUT= ±10V VAH= VEN= 2.4VMAX378VAL= 0.8V (Note 5)MAX379(Note 2)MAX379 only(Note 6)+25°CFull+25°CFull+25°CFullFull+25°CFullFullFullFull-50-1.0-200-100-10-600-300-15-500.10.12.03.0-0.50.033.04.00.5501.020010010600300+1550-50-2.0-200-100-20-600-300-15-500.10.12.03.0-1.00.033..01.0502.020010020600300+1550VnAnAnAkΩnA0°C to +70°Cand-40°C to +85°CMINTYPMAXPARAMETERSYMBOLCONDITIONSTEMPUNITSOFF Output Leakage CurrentIOUT(OFF)ON Channel Leakage CurrentAnalog Signal RangeDifferential OFF OutputLeakage CurrentFAULTOutput Leakage Current (with Input Overvoltage)Input Leakage Current(with Overvoltage)Input Leakage Current(with Power Supplies Off)CONTROLInput Low ThresholdInput High ThresholdInput Leakage Current (High or Low)2IOUT(ON)VANIDIFFIOUT(OFF)IIN(OFF)IIN(OFF)VOUT= 0V, VIN= ±60V(Notes 3, 4)VIN= ±60V, VOUT= ±10V(Notes 3, 4)VIN= ±75V, VEN= VOUT= 0VA0= A1= A2= 0V or 5V(Note 4)(Note 4)VA= 5V or 0V (Note 5)+25°CFull+25°C+25°C2010251020204020nAµAµAµAVALVAHIAFullFullFull2.4-1.00.82.41.0-1.00.8VV1.0µA_______________________________________________________________________________________元器件交易网www.cecb2b.com
High-Voltage, Fault-ProtectedAnalog MultiplexersELECTRICAL CHARACTERISTICS (continued)
(V+ = +15V, V- = -15V; VAH(Logic Level High) = +2.4V, VAL(Logic Level Low) = +0.8V, unless otherwise noted.)
-55°C to +125°CMINTYPMAXDYNAMICAccess TimeBreak-Before-Make Delay(Figure 2)Enable Delay (ON)Enable Delay (OFF)Settling Time (0.1%)(0.01%)“OFF Isolation”Channel Input CapacitanceChannel Output CapacitanceDigital Input CapacitanceInput to Output CapacitanceSUPPLYPositive Supply CurrentNegative Supply CurrentPower-Supply Range forContinuous OperationI+I-VOPVEN= 0.8V or 2.4VAll VA= 0V or 5VVEN= 0.8V or 2.4VAll VA= 0V or 5V(Note 7)+25°CFull+25°CFull+25°C±4.50.10.30.010.020.60.70.10.2±18±4.50.20.50.010.021.01.00.10.1±18mAmAVtAtON-tOFFtON(EN)tOFF(EN)tSETTOFF(ISO)CIN(OFF)COUT(OFF)CACDS(OFF)Figure 1VEN= +5V, VIN= ±10VA0, A1, A2strobedFigure 3Figure 3+25°C+25°C+25°CFull+25°CFull+25°CVEN= 0.8V, RL= 1kΩ, CL= 15pF+25°CV = 7VRMS, f = 100kHz+25°CMAX378+25°CMAX379+25°C+25°C501.23.5685251250.150300250.5200400750100050010001.23.5685251250.130010001.0250.5200400100015001.0µsnsnsnsµsdBpFpFpFpF0°C to +70°Cand-40°C to +85°CMINTYPMAXMAX378/MAX379PARAMETERSYMBOLCONDITIONSTEMPUNITSNote 2:When the analog signal exceeds +13.5V or -12V, the blocking action of Maxim’s gate structure goes into operation. Only
leakage currents flow and the channel ON resistance rises to infinity.
Note 3:The value shown is the steady-state value. The transient leakage is typically 50µA. See Detailed Description.Note 4:Guaranteed by other static parameters.
Note 5:Digital input leakage is primarily due to the clamp diodes. Typical leakage is less than 1nA at +25°C.Note 6:Leakage currents not tested at TA= cold temp.
Note 7:Electrical characteristics, such as ON Resistance, will change when power supplies other than ±15V are used.
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High-Voltage, Fault-ProtectedAnalog MultiplexersMAX378/MAX379__________________________________________Typical Operating CharacteristicsINPUT LEAKAGE vs.
INPUT VOLTAGE WITH V+ = V- = 0V
MAX378-1OFF CHANNEL LEAKAGE CURRENT vs.INPUT VOLTAGE WITH ±15V SUPPLIES
MAX378-2OUTPUT LEAKAGE CURRENT vs. OFF CHANNEL
OVERVOLTAGE WITH ±15V SUPPLIES
MAX378-31m100µINPUT CURRENT (A)10µ
OPERATINGRANGE100µ10µ1µ
OPERATINGRANGE10n
1nIOUT(OFF) (A)OPERATINGRANGEIIN(OFF) (A)1µ100n10n1n100p
100n
+60V-60V10n1n100p
100p
10p
+80V-80V10p1p-120
1p-120
10p-100
-500VIN (V)
50100-600VIN (V)
60120-600VIN(OFF) (V)
60
+60V120
DRAIN-SOURCE ON-RESISTANCE vs.
ANALOG INPUT VOLTAGE
+3.5V+13V5RDS(ON) (kΩ)432
+4V±5VSUPPLIES+13V±15VSUPPLIES6
MAX37847
NOTE:Typical RDS(ON)match @ +10V
Analog in (±15V supplies) = 2%for lowest to highest RDS(ON)channel; @ -10V Analog in, match = 3%.
10-15
-10
-5
0
5
10
15
20
ANALOG INPUT (V)
MAX378: VAH = 3.0V50%ADDRESSDRIVE (VA)0VVA+VAH50ΩA2IN1IN2A1A0ENGND±10VMAX378IN2-IN7IN8OUT10M14pF10VPROBE±+10VOUTPUT A90%tA-10VFigure 1. Access Time vs. Logic Level (High)4
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High-Voltage, Fault-ProtectedAnalog MultiplexersMAX378/MAX379MAX358: VAH = 3.0VADDRESSDRIVE (VA)VA50%50%OUTPUT50Ω2.4VA20VA1A0ENMAX378*IN2-IN7IN8OUTGND1k12.5pFVOUTIN1IN2+5VtOPEN*SIMILAR CONNECTION FOR MAX379Figure 2. Break-Before-Make Delay (tOPEN)MAX378: VIN1+10VAH = 3.0VA2ENABLE DRIVE50%0VA1MAX378*IN2-IN7A090%OUTPUTVAENOUTGND90%50Ω1k12.5pFtON(EN)tOFF(EN)*SIMILAR CONNECTION FOR MAX379Figure 3. Enable Delay (tON(EN), tOFF(EN))+5V+15V0VV-A0V-A0A1+5VorA1A20VA2ENMAX378ENMAX378IIN1OUTIIN1OUTIN8±60VVV-GND10k±75VV-GND10k±10VANALOG-15V0VSIGNALFigure 4. Input Leakage Current (Overvoltage)Figure 5. Input Leakage Current (with Power Supplies OFF)_______________________________________________________________________________________
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High-Voltage, Fault-ProtectedAnalog MultiplexersMAX378/MAX379Truth Table—MAX378
A2X00001111
A1X00110011
A0X01010101
EN011111111
+15VTHERMOCOUPLESTRAIN GUAGE4-20mA LOOPTRANSMITTERV++15VTruth Table—MAX379
ONSWITCHNONE12345678
A1X0011
A0X0101
EN01111
ONSWITCHNONE1234
Note:Logic “0” = VAL≤0.8V, Logic “1” = VAH≥2.4V
IN1IN2IN3IN4IN5IN6OUTMAX420MAX378+15VV+-15V1MIN1IN2100k+10VGAIN REFERENCEZERO REFERENCEIN7IN8V--15VGNDOUTDG508AMAX358ORMAX378V--15VGND10kIN3IN4IN5111Ω1kFigure 6. Typical Data Acquisition Front End_______________Typical ApplicationsFigure 6 shows a typical data acquisition systemusing the MAX378 multiplexer. Since the multiplexeris driving a high-impedance input, its error is a func-tion of its own resistance (RDS(ON)) times the multi-plexer leakage current (IOUT(ON)) and the amplifierbias current (IBIAS):
VERR= RDS(ON)x (IOUT(ON)+ IBIAS(MAX420))
= 2.0kΩx (2nA + 30pA)= 18.0µV maximum error
In most cases, this error is low enough that preamplifi-cation of input signals is not needed, even with verylow-level signals such as 40µV/°C from type J thermo-couples.
6
In systems with fewer than eight inputs, an unused chan-nel can be connected to the system ground referencepoint for software zero correction. A second channelconnected to the system voltage reference allows gaincorrection of the entire data acquisition system as well.A MAX420 precision op amp is connected as a pro-grammable-gain amplifier, with gains ranging from 1 to10,000. The guaranteed 5µV unadjusted offset of theMAX420 maintains high signal accuracy, while program-mable gain allows the output signal level to be scaled tothe optimum range for the remainder of the data acqui-sition system, normally a Sample/Hold and A/D. Sincethe gain-changing multiplexer is not connected to theexternal sensors, it can be either a DG508A multiplexeror the fault-protected MAX358 or MAX378.
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High-Voltage, Fault-ProtectedAnalog MultiplexersInput switching, however, must be done with a fault-protected MAX378 multiplexer, to provide the level ofprotection and isolation required with most data acqui-sition inputs. Since external signal sources may contin-ue to supply voltage when the multiplexer and systempower are turned off, non-fault-protected multiplexers,or even first-generation fault-protected devices, willallow many milliamps of fault current to flow from out-side sources into the multiplexer. This could result indamage to either the sensors or the multiplexer. A non-fault-protected multiplexer will also allow input overvolt-ages to appear at its output, perhaps damagingSample/Holds or A/Ds. Such input overdrives may alsocause input-to-input shorts, allowing the high currentoutput of one sensor to possibly damage another.
The MAX378 eliminates all of the above problems. ItMAX378/MAX379+60VOVERVOLTAGEN-CHANNEL MOSFETIS TURNED OFFBECAUSE VGS = -60VQ1SGDSQ2DGSQ3DGFigure 8. +60V Overvoltage with Multiplexer Power OFFnot only limits its output voltage to safe levels, with orwithout power applied (V+ and V-), but also turns allchannels off when power is removed. This allows it todraw only sub-microamp fault currents from the inputs,and maintain isolation between inputs for continuous-15V+15V-15V+60V FORCEDinput levels up to ±75V with power supplies off.
ON COMMONOUTPUT_______________Detailed DescriptionLINE BYEXTERNALFault Protection Circuitry-60VQ1-60VQ2Q3CIRCUITRYThe MAX378/MAX379 are fully fault protected for contin-OVERVOLTAGEuous input voltages up to ±60V, whether or not the V+and V- power supplies are present. These devices useN-CHANNEL MOSFETa “series FET” switching scheme which not only pro-IS TURNED OFFBECAUSE VGS = +45V-15V FROM+15V FROMN-CHANNELtects the multiplexer output from overvoltage, but alsoDRIVERSDRIVERSMOSFET IS OFFlimits the input current to sub-microamp levels.
P-CHANNELFigures 7 and 8 show how the series FET circuit pro-MOSFET IS OFFtects against overvoltage conditions. When power isoff, the gates of all three FETs are at ground. With a -60VFigure 9. -60V Overvoltage on an OFF Channel withinput, N-channel FET Q1 is turned on by the +60V gate-Multiplexer Power Supply ON-15V+15V-15V-60VQ1-60VQ2Q3Q1+13.5VQ2Q3+13.5VOVERVOLTAGESDSDSD+60VOVERVOLTAGEOUTPUTN-CHANNEL MOSFETIS TURNED ONGGGN-CHANNEL MOSFETVTN = +1.5VBECAUSE VGS = +60VIS TURNED ONBECAUSE VGS = -45V+15V FROM-15V FROMN-CHANNELP-CHANNELDRIVERSDRIVERSMOSFET IS ONMOSFET IS OFFFigure 7. -60V Overvoltage with Multiplexer Power OFFFigure 10. +60V Overvoltage Input to the ON Channel_______________________________________________________________________________________
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High-Voltage, Fault-ProtectedAnalog Multiplexersto-source voltage. The P-channel device (Q2), howev-er, has +60V VGSand is turned off, thereby preventingthe input signal from reaching the output. If the inputvoltage is +60V, Q1 has a negative VGS, which turns itoff. Similarly, only sub-microamp leakage currents canflow from the output back to the input, since any volt-age will turn off either Q1 or Q2.
Figure 9 shows the condition of an OFF channel withV+ and V- present. As with Figures 7 and 8, either anN-channel or a P-channel device will be off for anyinput voltage from -60V to +60V. The leakage currentwith negative overvoltages will immediately drop to afew nanoamps at +25°C. For positive overvoltages,that fault current will initially be 40µA or 50µA, decayingover a few seconds to the nanoamp level. The timeconstant of this decay is caused by the discharge ofstored charge from internal nodes, and does not com-promise the fault-protection scheme.
Figure 10 shows the condition of the ON channel withV+ and V- present. With input voltages less than ±10V,all three FETs are on and the input signal appears at theoutput. If the input voltage exceeds V+ minus the N-channel threshold voltage (VTN), then the N-channelFET will turn off. For voltages more negative than V-minus the P-channel threshold (VTP), the P-channeldevice will turn off. Since VTNis typically 1.5V and VTPis typically 3V, the multiplexer’s output swing is limitedto about -12V to +13.5V with ±15V supplies.
The Typical Operating Characteristicsgraphs show typi-cal leakage vs. input voltage curves. Although the max-imum rated input of these devices is ±65V, theMAX378/MAX379 typically have excellent performanceup to ±75V, providing additional margin for the unknowntransients that exist in the real world. In summary, theMAX378/MAX379 provide superior protection from allfault conditions while using a standard, readily pro-duced junction-isolated CMOS process.
MAX378/MAX379ly connected to the output. In a typical data acquisitionsystem, such as in Figure 6, the dominant delay is not theswitching time of the MAX378 multiplexer, but is the set-tling time of the following amplifiers and S/H. Another limit-ing factor is the RC time constant of the multiplexerRDS(ON)plus the signal source impedance multiplied bythe load capacitance on the output of the multiplexer.Even with low signal source impedances, 100pF of capac-itance on the multiplexer output will approximately doublethe settling time to 0.01% accuracy.
Operation with Supply VoltageOther than ±15VThe main effect of supply voltages other than ±15V isthe reduction in output signal range. The MAX378 limitsthe output voltage to about 1.5V below V+ and about 3Vabove V-. In other words, the output swing is limited to+3.5V to -2V when operating from ±5V. The TypicalOperating Characteristicsgraphs show typical RDS(ON),for ±15V, ±10V, and ±5V power supplies. Maxim testsand guarantees the MAX378/MAX379 for operation from±4.5V to ±18V supplies. The switching delays areincreased by about a factor of 2 at ±5V, but break-before-make action is preserved.
The MAX378/MAX379 can be operated with a single +9Vto +22V supply, as well as asymmetrical power suppliessuch as +15V and -5V. The digital threshold will remainapproximately 1.6V above GND and the analog character-istics such as RDS(ON)are determined by the total voltagedifference between V+ and V-. Connect V- to 0V whenoperating with a +9V to +22V single supply.
This means that the MAX378/MAX379 will operate withstandard TTL-logic levels, even with ±5V power sup-plies. In all cases, the threshold of the EN pin is thesame as the other logic inputs.
Table 1a. MAX378 Charge InjectionSupply Voltage±5VAnalog Input Level+1.7V0V-1.7V+5V0V-5V+10V0V-10VInjected Charge+100pC+70pC+45pC+200pC+130pC+60pC+500pC+180pC+50pCSwitching Characteristicsand Charge InjectionTable 1 shows typical charge-injection levels vs.power-supply voltages and analog input voltage. Notethat since the channels are well matched, the differen-tial charge injection for the MAX379 is typically lessthan 5pC. The charge injection that occurs duringswitching creates a voltage transient whose magnitudeis inversely proportional to the capacitance on the mul-tiplexer output.
The channel-to-channel switching time is typically 600ns,with about 200ns of break-before-make delay. This 200nsbreak-before-make delay prevents the input-to-input shortthat would occur if two input channels were simultaneous-8
±10V±15VTest Conditions: CL= 1000pF on multiplexer output; the tabu-lated analog input level is applied to channel 1; channels 2through 8 are open circuited. EN = +5V, A1 = A2 = 0V, A0 istoggled at 2kHz rate between 0V and 3V. +100pC of chargecreates a +100mV step when injected into a 1000pF loadcapacitance._______________________________________________________________________________________元器件交易网www.cecb2b.com
High-Voltage, Fault-ProtectedAnalog MultiplexersTable 1b. MAX379 Charge InjectionSupplyVoltageAnalogInput Level+1.7V0V-1.7V+5V0V-5V+10V0V-10VInjected ChargeOut A+105pC+73pC+48pC+215pC+135pC+62pC+525pC+180pC+55pCOut B+107pC+74pC+50pC+220pC+139pC+63pC+530pC+185pC+55pCDifferentialA-B-2pC-1pC-2pC-5pC-4pC-1pC-5pC-5pC0pC±5V±10V±15VTest Conditions: CL= 1000pF on Out A and Out B; the tabulat-ed analog input level is applied to inputs 1A and 1B; channelsrents as the off-channel input voltages are varied. TheMAX378 output leakage varies only a few picoamps asall seven off inputs are toggled from -10V to +10V. Theoutput voltage change depends on the impedance levelat the MAX378 output, which is RDS(ON)plus the inputsignal source resistance in most cases, since the loaddriven by the MAX378 is usually a high impedance. Fora signal source impedance of 10kΩor lower, the DCcrosstalk exceeds 120dB.
Table 2 shows typical AC crosstalk and off-isolation per-formance. Digital feedthrough is masked by the analogcharge injection when the output is enabled. When theoutput is disabled, the digital feedthrough is virtuallyunmeasurable, since the digital pins are physically iso-lated from the analog section by the GND and V- pins.The ground plane formed by these lines is continuedMAX378/MAX3792 through 4 are open circuited. EN = +5V, A1 = 0V, A0 is tog-onto the MAX378/MAX379 die to provide over 100dBgled from 0V to 3V at a 2kHz rate.isolation between the digital and analog sections.
Digital Interface LevelsThe typical digital threshold of both the address linesand the EN pin is 1.6V, with a temperature coefficient ofTable 2a. Typical Off-Isolationabout -3mV/°C. This ensures compatibility with 0.8V toRejection Ratio
2.4V TTL-logic swings over the entire temperaturerange. The digital threshold is relatively independent ofFrequency100kHz
500kHz
1MHz
the supply voltages, moving from 1.6V typical to 1.5Vtypical as the power supplies are reduced from ±15V toOne Channel Driven74dB72dB66dB±5V. In all cases, the digital threshold is referenced toGND.
All Channels Driven
dB
48dB
44dB
The digital inputs can also be driven with CMOS-logicTest Conditions: VIN= 20VP-Pat the tabulated frequency, levels swinging from either V+ to V- or from V+ to GND.RL= 1.5kΩbetween OUT and GND, EN = 0V.
The digital input current is just a few nanoamps of leak-age at all input voltage levels, with a guaranteed maxi-OIRR = 20 Log ____________
20VP-P
mum of 1µA. The digital inputs are protected from ESDVOUT (P-P)
by a 30V zener diode between the input and V+, andcan be driven ±4V beyond the supplies without drawingexcessive current.
Table 2b. Typical CrosstalkOperation as a DemultiplexerThe MAX378/MAX379 will function as a demultiplexer,Rejection Ratio
where the input is applied to the OUT pin, and the inputFrequency100kHz
500kHz
1MHz
pins are used as outputs. The MAX378/MAX379 pro-vide both break-before-make action and full fault protec-FL= 1.5k70dB68dBdBtion when operated as a demultiplexer, unlike earliergenerations of fault-protected multiplexers.
RL= 10k
62dB
46dB
42dB
Channel-to-Channel Crosstalk,Test Conditions: Specified RLconnected from OUT to GND,Off Isolation, and Digital FeedthroughEN = +5V, A0 = A1 = A2 = +5V (Channel 1 selected). 20VP-Pat the tabulated frequency is applied to Channel 2. All otherAt DC and low frequencies, channel-to-channelchannels are open circuited. Similar crosstalk rejection can becrosstalk is caused by variations in output leakage cur-
observed between any two channels.
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High-Voltage, Fault-ProtectedAnalog MultiplexersMAX378/MAX379_____________________________________________Pin Configurations (continued)TOP VIEWA01EN2N.C.3N.C.4V-5IN16IN27IN38IN49N.C.10N.C.11OUT1224A123A222GND21N.C.A01EN2N.C.3N.C.4V-5IN1A6IN2A7IN3A824A123N.C.22GND21N.C.MAX37820V+19IN518IN617N.C.16IN715N.C.14N.C.13IN8MAX37920V+19IN1B18IN2B17IN3B16IN4B15N.C.14N.C.13OUTBIN4A9N.C.10N.C.11OUTA12SOSO1N.C.1N.C.V-4IN15N.C.6IN27IN3818GND17V+V-4IN1A5N.C.6IN2A7IN3A819GND2A02A020A119A220A13EN3EN18V+17IN1BMAX37816N.C.15IN514IN6MAX37916N.C.15IN2B14IN3BOUT10N.C.11IN812IN713OUTA10N.C.11OUTB12LCCIN4ALCC10______________________________________________________________________________________IN4B139IN49元器件交易网www.cecb2b.com
High-Voltage, Fault-ProtectedAnalog Multiplexers_Ordering Information (continued)PARTMAX379CPEMAX379CWGMAX379CJEMAX379C/DMAX379EPEMAX379EWGMAX379EJEMAX379MJEMAX379MLPTEMP. RANGE0°C to +70°C0°C to +70°C0°C to +70°C0°C to +70°C-40°C to +85°C-40°C to +85°C-40°C to +85°C-55°C to +125°C-55°C to +125°CPIN-PACKAGE16 Plastic DIP24 Wide SO16 CERDIPDice**16 Plastic DIP24 Wide SO16 CERDIP16 CERDIP20 LCC*_________________Chip TopographiesMAX378IN8OUT IN7IN4MAX378/MAX379 IN7IN30.229\"(5.816mm)* Contact factory for availability.**The substrate may be allowed to float or be tied to V+ (JI CMOS). IN6IN2 IN5 IN1V+V- GNDA2A1A0EN0.151\"(3.835mm)NOTE: Connect substrate to V+ or leave it floating.MAX379OUTBOUTAIN4A IN4B IN3BIN3A0.229\"(5.816mm) IN2BIN2A IN1B IN1AV+V- GNDA1A0EN0.151\"(3.835mm)NOTE: Connect substrate to V+ or leave it floating.______________________________________________________________________________________11
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High-Voltage, Fault-ProtectedAnalog MultiplexersMAX378/MAX379________________________________________________________Package InformationDIMAA1BCEeHLINCHESMAXMIN0.1040.0930.0120.0040.0190.0140.0130.0090.2990.2910.0500.4190.3940.0500.016MILLIMETERSMINMAX2.352.650.100.300.350.490.230.327.407.601.2710.0010.650.401.27DAeB0.101mm0.004in.0°- 8°A1CLEHWide SOSMALL-OUTLINEPACKAGE(0.300 in.)DIMDDDDDPINS1618202428INCHESMINMAX0.3980.4130.4470.4630.4960.5120.5980.6140.6970.713MILLIMETERSMINMAX10.1010.5011.3511.7512.6013.0015.2015.6017.7018.1021-0042AD1EDA3AA2E1DIMAA1A2A3BB1CDD1EE1eeAeBLαINCHESMAXMIN0.200––0.0150.1500.1250.0800.0550.0220.0160.0650.0500.0120.0080.7650.7450.0300.0050.3250.3000.2800.2400.100 BSC0.300 BSC0.400–0.1500.11515˚0˚MILLIMETERSMINMAX–5.080.38–3.183.811.402.030.410.561.271.650.200.3018.9219.430.130.767.628.266.107.112. BSC7.62 BSC–10.162.923.810˚15˚21-587ALA1eBαCB1eAeB16-PIN PLASTICDUAL-IN-LINEPACKAGEMaxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses areimplied. Maxim reserves the right to change the circuitry and specifications without notice at any time.12__________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600©1994 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
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