MAX368CPN+ - 8:1 Fault-Protected Analog Mux, 1.8kOhm | Maxim
N.º da peça: MAX368CPN+ ✓ Ativo| Qtd. | Preço unitário | Total |
|---|---|---|
| 1 | $12.5 | $12,50 |
| 10 | $11.25 | $112,50 |
| 100 | $10 | $1.000,00 |
| 500 | $8.95 | $4.475,00 |
| 1.000 | $7.98 | $7.980,00 |
MAX368CPN+ Visão geral
An analog multiplexer is a switch network that selects one of several analog input signals and routes it to a single output under digital control. Within the signal-chain hierarchy, the analog multiplexer sits between sensors or signal sources and amplifiers or ADCs, and is itself a member of the broader analog switch IC family. Fault-protected multiplexers add a critical layer: their inputs tolerate fault voltages far beyond the supply rails, and outputs are forced to a high-impedance state when power is removed, protecting downstream circuitry.
Key features of the MAX368 include overvoltage protection up to plus or minus 35V at the analog inputs, channels automatically turned off when power is lost, all digital inputs TTL and CMOS compatible, and internal data latches for channel selection so the addressed channel is held without continuous drive of the address lines.
Technical depth: the device operates from plus or minus 15V supplies with 5 nA typical leakage, and switches in approximately 1.5 microseconds on-time and 1 microsecond off-time with break-before-make switching action, ensuring the selected channels never short together during transitions. The C-grade temperature specification covers commercial ranges; E and M grades exist for extended and military environments.
Typical applications include industrial data acquisition front ends where wiring faults or misconnection would otherwise destroy a standard CMOS mux, test and measurement input selector stages, and ATE (automated test equipment) channel routing where inputs may exceed supply rails.
Design consideration: the 1.8 kOhm on-resistance must be accounted for in settling-time budgets when driving sample-and-hold or ADC inputs, particularly at higher source capacitance.
This page synthesizes distributor pricing, verified drop-in grade variants, and practical design notes beyond the summary on the manufacturer datasheet.
Alternativas drop-in para MAX368CPN+ — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
Ferramenta de comparação rápida — selecione peças alternativas para comparação lado a lado:
MAX368EJN
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MAX368EPN+
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MAX368MJN
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MAX368CPN+ Classificações máximas e características elétricas
| Função | Fault-protected analog multiplexer with latch |
| Canais | 8-channel (8:1) |
| On-Resistance | 1.8 kOhm |
| Overvoltage Protection | Up to +/-35 V |
| Switching Time (tON) | 1.5 us |
| Switching Time (tOFF) | 1 us |
| Switching Action | Break-before-make |
| Digital Input Compatibility | TTL and CMOS |
| Internal Data Latches | Yes, for channel selection |
| Power-Loss Behavior | Outputs channels turned off with power loss |
| Input Leakage Current | 5 nA |
| Tensão de alimentação | +/-15 V |
| Encapsulamento | 18-PDIP (0.300 in, 7.62 mm) |
| Tipo de montagem | Through Hole |
| Temperature Grade | C (commercial) |
| Lead Finish Suffix | + (lead-free / RoHS) |
Guia de Configuração de Pinos do MAX368CPN+ 18-pdip (0.300 in, 7.62 mm)
Configuração de pinos para MAX368CPN+ (pacote 18-pdip (0.300 in, 7.62 mm)). Este CI digital inclui GPIO, interfaces de comunicação (UART, SPI, I2C) e pinos de alimentação. Consulte o datasheet do fabricante para funções alternativas dos pinos e opções de configuração. Essencial para projeto de sistemas embarcados e layout de PCB.
Nenhum dado detalhado de pinagem disponível para MAX368CPN+.
Consulte a ficha técnica para a configuração completa dos pinos.
Aplicações típicas
MAX368CPN+ é adequado para 6 aplicaçãos: Industrial Data Acquisition Front End, Automated Test Equipment (ATE) Channel Routing, Test and Measurement Instrument Input Selectors, Legacy Board Repair and Sustaining Engineering, Sensor Signal Conditioning Multiplexing, Protection-Critical Audio/Video Routing.
Industrial Data Acquisition Front End
In industrial data acquisition systems, the MAX368CPN+ routes one of eight sensor signals to a shared amplifier or ADC stage. Its +/-35 V input fault protection is decisive: wiring mistakes, inductive transients, or miswired terminals that would destroy a standard CMOS multiplexer leave the MAX368 undamaged, and the faulted channel simply turns off while the remaining seven continue operating. According to the Maxim datasheet, channels are also turned off automatically when power is lost, preventing back-powering of the analog front end during brownout. The internal data latches hold the selected channel address without continuous microcontroller drive, freeing processor cycles in scanning designs. The trade-off is the 1.8 kOhm on-resistance, which requires settling-time budgeting before the ADC acquires each channel - acceptable for scanning rates up to roughly 100 ksps.
Recomendado
Automated Test Equipment (ATE) Channel Routing
Automated test equipment frequently routes multiple test points to a shared measurement instrument, and the MAX368CPN+ fits this role because test points are inherently unpredictable - a misprobed node can sit far outside the supply rails. The +/-35 V overvoltage protection allows the multiplexer to survive accidental connection to power rails, and the power-loss channel-off feature guarantees a defined high-impedance output state during equipment power-up and shutdown. Break-before-make switching with 1.5 us tON and 1 us tOFF timing (per the Maxim datasheet) prevents momentary shorts between two test nodes during channel changes, which could corrupt a measurement or damage the device under test. Internal latches let the test controller write a channel address once and move on, simplifying sequencer firmware.
Recomendado
Test and Measurement Instrument Input Selectors
Bench instruments such as data loggers, multimeter input stages, and multi-channel chart recorders use the MAX368CPN+ as a front-end channel selector. Fault protection up to +/-35 V means an operator connecting a probe to the wrong terminal does not destroy the input multiplexer - a common failure mode in standard CMOS designs. The 5 nA input leakage (per the Maxim datasheet) keeps loading errors negligible on high-impedance sources, and the TTL/CMOS-compatible address inputs interface directly with the instrument's control logic. Because the C-grade part covers the commercial temperature range, it suits bench and laboratory instruments. The through-hole PDIP-18 package also simplifies rework and field service, which matters for long-lived instrumentation products.
Recomendado
Legacy Board Repair and Sustaining Engineering
The MAX368CPN+ in PDIP-18 through-hole packaging is a natural fit for repairing and sustaining legacy industrial and telecom boards that were designed around this exact multiplexer. Drop-in grade variants (MAX368EJN, MAX368EPN+, MAX368MJN) share the same 18-pin PDIP footprint, so a failed commercial-grade part can be swapped for an extended-grade variant without PCB modification. The '+' suffix guarantees lead-free, RoHS-compliant assembly, meeting current repair-material requirements on boards that originally used leaded parts. According to distributor data (DigiKey, ships today; Octopart, 8 distributors as of 2026-10-11), sourcing remains straightforward. For obsolescence planning, verify stock of the E-grade variants since M-grade military stock tends to be scarcer.
Recomendado
Sensor Signal Conditioning Multiplexing
Multi-sensor nodes - thermocouple scanners, pressure-transducer arrays, and process-monitoring racks - use the MAX368CPN+ to share one signal-conditioning chain across eight sensors. Fault protection is valuable here because field wiring is exposed: a crushed cable or miswired terminal presenting up to +/-35 V turns off only the affected channel, per the Maxim datasheet, while the other seven sensors keep reporting. The internal latches freeze the selected channel address, which is useful in slow-scanning monitors where the controller sleeps between samples. The 5 nA leakage limits offset error on high-impedance sensor outputs. Designers should account for the 1.8 kOhm on-resistance when sizing the input resistor and any filter capacitance, since it forms part of the signal-path RC that determines settling accuracy.
Recomendado
Protection-Critical Audio/Video Routing
In audio and low-frequency video routing racks, the MAX368CPN+ selects one of eight signal sources while surviving hot-patching events: a technician plugging an input that carries a phantom or DC offset of up to +/-35 V will not destroy the switch, unlike ordinary CMOS multiplexers. Break-before-make switching (1.5 us tON / 1 us tOFF per the Maxim datasheet) prevents audible clicks and signal shorts during source changes. The 1.8 kOhm on-resistance is acceptable in high-level line signals buffered by op-amps, though designers should insert a buffer after the mux to isolate downstream loading and preserve bandwidth. TTL/CMOS-compatible control lines let an MCU or FPGA manage source selection directly, and the internal latches keep the selection stable across control-bus refresh cycles.
Recomendado
Resumo dos produtos recomendados
Dados de referência de engenharia para MAX368CPN+ — comparação, orientação de projeto e informações de conformidade.
Guia de seleção
Comparação com alternativas
| Parâmetro | Este produto | MAX368EJN | MAX368EPN+ | MAX368MJN |
|---|---|---|---|---|
| Package | 18-PDIP (0.300 in, 7.62 mm) | 18-PDIP (0.300 in) - same | 18-PDIP (0.300 in) - same | 18-PDIP (0.300 in) - same |
| Brand | Analog Devices / Maxim Integrated | Analog Devices / Maxim Integrated | Analog Devices / Maxim Integrated | Analog Devices / Maxim Integrated |
| Temperature Grade | C (commercial) | E (extended) | E (extended) | M (military) |
| Configuration | 8:1 multiplexer with latch | 8:1 multiplexer with latch | 8:1 multiplexer with latch | 8:1 multiplexer with latch |
| On-Resistance | 1.8 kOhm | 1.8 kOhm | 1.8 kOhm | 1.8 kOhm |
| Fault Protection | +/-35 V | +/-35 V | +/-35 V | +/-35 V |
| Digital Input Compatibility | TTL and CMOS | TTL and CMOS | TTL and CMOS | TTL and CMOS |
Principais diferenciais
- True input fault tolerance (vs MAX368EJN)
- Lead-free availability (vs MAX368EJN)
- Extended-grade drop-in option (vs MAX368EPN+)
- Internal data latches (vs Standard CMOS muxes (e.g., CD4051 class))
Notas de projeto
Do not assume the MAX368CPN+ behaves like a standard low-RON CMOS multiplexer. Its 1.8 kOhm on-resistance is roughly 10-30x higher than modern switches, so any signal bandwidth or settling calculation must include it. When driving a capacitive load or an ADC sample capacitor, compute the RC time constant with 1.8 kOhm and allow at least 7 time constants for 0.1% settling. Failure to budget this is the most common root cause of 'slow' multiplexed acquisition systems.
Because the part is through-hole PDIP-18, place the analog COM output trace away from the digital address lines (A0-A2 and latch enable) to prevent capacitive feedthrough glitches during address transitions. The break-before-make action (1 us tOFF) already prevents channel-to-channel shorts, but adding a small RC (for example 100 Ohm / 100 pF, estimated from typical mux practice - verify against the manufacturer datasheet typical application circuit) on the COM output improves settling into ADC sample capacitors.
Operate the MAX368CPN+ from +/-15 V rails as specified in the datasheet; the fault-protection topology relies on the full supply span. Do not use the part on reduced rails (for example +/-5 V) and still expect +/-35 V fault tolerance - fault ratings are specified relative to the nominal supply configuration. During power sequencing, remember that all channels turn off when power is removed, so downstream circuitry sees high impedance at power-down; design the following stage so a floating input does not cause latch-up or erratic readings.
Informações de conformidade
The '+' suffix on MAX368CPN+ denotes the lead-free / RoHS-compliant version per DigiKey and Hotenda listings. REACH, halogen-free, and conflict-minerals status were not stated in the provided data.
