MAX1240CCPA - 12-Bit 73ksps Serial ADC, 2.7V | Maxim Integrated
N.º da peça: MAX1240CCPA ✗ Fim de vida| Qtd. | Preço unitário | Total |
|---|---|---|
| 1 | $7.5 | $7,50 |
| 10 | $6.8 | $68,00 |
| 100 | $6.1 | $610,00 |
| 500 | $5.4 | $2.700,00 |
| 1.000 | $4.75 | $4.750,00 |
MAX1240CCPA Visão geral
An ADC (analog-to-digital converter) is a mixed-signal integrated circuit that converts continuous analog voltages into discrete digital codes. The successive-approximation register (SAR) architecture used here performs a binary search across an internal capacitive DAC, settling one bit per clock cycle to produce a 12-bit code in N conversion cycles. SAR ADCs sit within the data-converter family alongside delta-sigma, pipeline, and flash converters, and are favored for low-power, medium-speed, single-shot sampling in instrumentation and portable equipment.
Key features of the MAX1240CCPA include an internal 2.5V reference (eliminating an external reference IC), 4.5 mW typical power consumption at 73 ksps, 5 uW power-down mode for battery savings, and an 8-pin PDIP footprint that simplifies through-hole prototyping. The differential nonlinearty is +/-1 LSB max with no missing codes over the operating range. Bipolar input signals can be accommodated by shifting the input common-mode voltage with a resistor network when an external reference is used.
Typical applications include portable data acquisition, pen digitizers, battery-powered instrumentation, loop-powered sensors, and isolated industrial monitoring. The internal reference and small footprint make it a strong choice where board area, BOM count, and quiescent current all matter - for example, handheld multimeters and 4-20 mA loop-powered transmitters. The 3-wire serial interface glues directly to most microcontrollers without external glue logic.
When designing with this part, ensure the supply decoupling (10uF + 0.1uF) is placed within 5 mm of the VDD pin. The reference bypass capacitor (4.7uF typical) is mandatory - omitting it degrades conversion accuracy. The SHDN pin allows the supply current to drop to under 10 uA between conversions for battery-powered duty-cycled designs. This page synthesizes distributor pricing, drop-in alternatives, and practical engineering guidance not found in the manufacturer datasheet.
Alternativas drop-in para MAX1240CCPA — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
Variantes desta série
Modelos da mesma série compatíveis como drop-in com MAX1240CCPA (mesmo formato e footprint) — diferindo em Data Interface, Input Type, Mounting Type, Operating Temperature, Package.
Ferramenta de comparação rápida — selecione peças alternativas para comparação lado a lado:
MAX1240CCPA+
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MAX1240BCPA+
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MAX1240AEPA+
✅ Drop-In ⚠️ Especificações não verificadas📋 Alternativa de referência (fora do catálogo)
MAX1240BEPA+
✅ Drop-In✓ Em estoque
$5.55 / unidade
Ver ficha técnica →MAX1241CCPA+
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MAX1240CCPA Classificações máximas e características elétricas
| Resolução | 12 bits |
| Number of Channels | 1 |
| Taxa de amostragem | 73 ksps |
| Input Type | Single-Ended |
| Architecture | SAR (Successive Approximation) |
| Tensão de alimentação | +2.7 V to +3.6 V |
| Supply Current (typ) | 1.5 mA at 73 ksps |
| Power-Down Current | 5 uW (typ) |
| Internal Reference | 2.5 V |
| Conversion Time | 7.5 us |
| Track/Hold Acquisition | 1.5 us |
| Data Interface | SPI / QSPI / MICROWIRE-compatible (3-wire serial) |
| Temperatura de operação | 0 C to +70 C (commercial, "C" suffix) |
| Encapsulamento | 8-pin PDIP (CCPA = PDIP-8, 0.300 inch) |
| Tipo de montagem | Through-Hole |
| Nível MSL | 1 (unlimited, through-hole) |
| Lifecycle | Obsolete (per distributor listings) |
Configuração de pinos do MAX1240CCPA
| Pino 1 | VDD — +2.7V to +3.6V supply input; bypass with 10uF + 0.1uF |
| Pino 2 | AIN — Analog input; single-ended input range 0 to VDD |
| Pino 3 | REF — Internal 2.5V reference output; bypass with 4.7uF to AGND |
| Pino 4 | AGND — Analog ground |
| Pino 5 | DGND — Digital ground |
| Pino 6 | DOUT — Serial data output; 12-bit MSB-first on SCLK falling edges |
| Pino 7 | SCLK — Serial clock input; up to 2.1 MHz |
| Pino 8 | CS — Chip select, active low; drives SHDN when tied to GND |
Aplicações típicas
MAX1240CCPA é adequado para 7 aplicaçãos: Portable Data Acquisition, Battery-Powered Instrumentation, Loop-Powered 4-20 mA Sensor Transmitters, Pen Digitizers and Touch Tablets, Isolated Industrial Monitoring, Portable Patient Monitoring, Automotive Sensor Interfaces.
Portable Data Acquisition
The MAX1240CCPA fits portable data acquisition because of its 12-bit resolution, 73 ksps sampling rate, and 5 uW power-down mode for duty-cycled battery operation. The internal 2.5V reference eliminates an external reference IC, reducing BOM count in space-constrained handheld designs. Placed on a 4-layer PCB with the MCU SPI bus and a 10uF + 0.1uF VDD bypass network, it delivers full 12-bit accuracy across the 0-2.5V input range while drawing under 1.5 mA during active conversion. The 8-pin PDIP footprint supports through-hole prototyping and field-replaceable instrumentation modules.
Recomendado
Battery-Powered Instrumentation
The MAX1240CCPA suits battery-powered instrumentation thanks to its +2.7V to +3.6V single supply that runs directly from a single Li-ion cell, plus its 5 uW power-down mode for sleep intervals between conversions. Internal 2.5V reference trims to +/-1% and removes the need for a separate reference IC, saving both board area and quiescent current. Used in handheld DMMs and field data loggers, the MAX1240CCPA typically runs at 1-10 ksps effective rate, drawing under 200 uA average from a 3V cell - good for weeks of operation on standard batteries.
Recomendado
Loop-Powered 4-20 mA Sensor Transmitters
The MAX1240CCPA is well-suited to loop-powered 4-20 mA sensor transmitters where total loop current must stay below 3.6 mA for the sensor electronics. Its 1.5 mA active supply current and 5 uW power-down mode leave ample current budget for the 4-20 mA loop regulator and sensor excitation. The 12-bit resolution over a 1.25V input span yields 305 uV LSB - more than adequate for thermocouple, RTD, and bridge-sensor digitization. The internal 2.5V reference can also serve as the bridge excitation rail, further reducing external component count.
Recomendado
Pen Digitizers and Touch Tablets
The MAX1240CCPA handles the position-sensing analog front end in pen digitizers and touch tablets. The 73 ksps sampling rate supports 100+ points-per-second pen tracking, while the 12-bit resolution over a 0-VDD input span provides sub-1000 LSB position quantization across typical 12-inch tablets. SPI/QSPI/MICROWIRE-compatible interface connects directly to the digitizer controller MCU. Low power consumption extends battery life in wireless pen-tablet designs, and the small 8-pin PDIP package simplifies the analog mixed-signal PCB layout by isolating the ADC away from noisy digital regions.
Recomendado
Isolated Industrial Monitoring
The MAX1240CCPA serves isolated industrial monitoring modules where one side of an isolation barrier needs to digitize analog sensor signals. Its 3-wire SPI interface crosses digital isolators cleanly with only three channels required (CS, SCLK, DOUT), minimizing the isolator cost. The +2.7V to +3.6V supply fits 3.3V isolated rails commonly derived from small DC-DC converters on the field side. Internal 2.5V reference allows direct connection to 0-2.5V sensor outputs without external scaling, and the commercial temperature grade (0 C to +70 C) covers most indoor control-cabinet environments.
Recomendado
Portable Patient Monitoring
The MAX1240CCPA fits portable patient monitoring devices such as pulse oximeters, single-channel ECG patches, and wearable vital-sign monitors. Its 12-bit resolution digitizes pulse-oximeter photodiode currents over a 0-2.5V range with sufficient accuracy for SpO2 calculation. The 5 uW power-down mode extends battery life to multiple days between charges - a key wearability requirement. The 8-pin PDIP footprint aids through-hole prototyping for medical device labs, and the +2.7V to +3.6V supply runs directly from a Li-ion cell.
Recomendado
Automotive Sensor Interfaces
The MAX1240CCPA suits automotive sensor interface modules such as cabin temperature sensors, battery monitor inputs, and HVAC controls. Its 12-bit resolution over the 0-2.5V input span provides ample accuracy for these low-bandwidth applications, while the 73 ksps sampling rate exceeds the needs of slow thermal and pressure sensors. The internal 2.5V reference can serve as a low-current excitation source for resistive sensor bridges. For under-hood or engine-compartment placement, the MAX1240AEPA+ (AEC-Q100 variant) is the preferred choice; the MAX1240CCPA suits cabin and body-electronics applications only.
Recomendado
Resumo dos produtos recomendados
Dados de referência de engenharia para MAX1240CCPA — comparação, orientação de projeto e informações de conformidade.
Guia de seleção
Comparação com alternativas
| Parâmetro | Este produto | MAX1240CCPA+ | MAX1240BCPA+ | MAX1240AEPA+ | MAX1240BEPA+ | MAX1241CCPA+ |
|---|---|---|---|---|---|---|
| Brand | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated |
| Package | PDIP-8 (0.300 inch) | PDIP-8 - same | PDIP-8 - same | PDIP-8 - same | PDIP-8 - same | PDIP-8 - same |
| Resolution | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits |
| Sampling Rate | 73 ksps | 73 ksps | 73 ksps | 73 ksps | 73 ksps | 73 ksps |
| Supply Voltage | +2.7V to +3.6V | +2.7V to +3.6V | +2.7V to +3.6V | +2.7V to +3.6V | +2.7V to +3.6V | +2.7V to +5.25V |
| Internal Reference | 2.5V internal | 2.5V internal | 2.5V internal | 2.5V internal | 2.5V internal | External reference required |
| Operating Temperature | 0 C to +70 C (commercial) | 0 C to +70 C | -40 C to +85 C (industrial) | -40 C to +85 C (automotive, AEC-Q100) | -40 C to +85 C | 0 C to +70 C |
| AEC-Q100 Qualified | No | No | No | Yes | No | No |
| Lead-Free (Pb-free) | No (SnPb finish) | Yes (RoHS) | Yes (RoHS) | Yes (RoHS) | Yes (RoHS) | Yes (RoHS) |
Principais diferenciais
- Internal 2.5V reference removes external reference IC (vs MAX1241CCPA+)
- Lower supply voltage matches single-cell Li-ion operation (vs MAX1241CCPA+)
- Commercial temperature grade is sufficient for most indoor applications (vs MAX1240BCPA+)
- 8-pin PDIP package aids through-hole prototyping and field repair (vs MAX1240BCSA+ (SO-8 variant))
Notas de projeto
VDD decoupling is critical - place a 10 uF tantalum (or ceramic with sufficient voltage rating) in parallel with a 0.1 uF ceramic within 5 mm of the VDD pin. Long VDD traces create inductive spikes that couple into the reference and degrade noise performance. For battery applications, add a 100 ohm ferrite bead in series with VDD to suppress switching noise from upstream DC-DC converters that could otherwise modulate the ADC reference.
Route analog and digital grounds as separate nets, joining only at the IC's AGND/DGND pins (star-ground configuration). Keep the AIN trace short and surrounded by analog ground; avoid running the SCLK and DOUT traces parallel to AIN. Estimated: AIN trace capacitance of 5 pF combined with the source impedance sets the track/hold settling time - constant 5 pF is well within the 1.5 us acquisition budget for source impedances below 1 kohm.
The internal 2.5V reference must be bypassed with a 4.7 uF capacitor at the REF pin to AGND - omitting this capacitor degrades conversion accuracy by several LSBs. For best noise performance, use a low-ESR ceramic or tantalum capacitor and place it within 3 mm of the pin. Driving AIN from a high-impedance source (>5 kohm) requires an external op-amp buffer because the internal switch-capacitor input draws charge transients during acquisition.
Do not apply analog input voltages outside 0 to VDD - voltages above VDD or below AGND forward-bias the input ESD diodes and inject noise into the substrate. Do not toggle SCLK while CS is high (idle) - stray SCLK edges can corrupt the conversion state machine. Do not leave CS floating - it must be tied either high (idle) or actively driven low during conversion. Estimated: a floating CS pin picks up ~50 mV of noise in pickup which can falsely trigger conversions.
Power dissipation in this ADC is dominated by the active-mode supply current (~1.5 mA at 73 ksps), so at VDD=3.6V the IC dissipates about 5.4 mW worst-case - no thermal management needed for the PDIP-8 package. The bigger thermal concern is local reference drift: the internal 2.5V reference shifts approximately +/-50 ppm/C, which over a 70 C rise equates to 8.75 mV of full-scale drift. For high-accuracy applications, use the SHDN mode to keep the IC warm only during active conversions, or add an external reference for tighter stability.
Informações de conformidade
MAX1240CCPA (no + suffix) is a SnPb (leaded) PDIP-8 - non-RoHS. The lead-free RoHS variant is MAX1240CCPA+ (different orderable part number). REACH and conflict-mineral status not explicitly documented in the verified web data. AEC-Q100 qualification requires the MAX1240AEPA+ variant. Recommend MAX1240CCPA+ for new RoHS-compliant designs.
