My Inquiry
My Account
Analog Devices Inc./Maxim Integrated MAX1240ACSA+
- Part No.:
- MAX1240ACSA+
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Category:
- Analog to Digital Converters (ADC)
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
MAX1240ACSA+.pdf
- Description:
- IC ADC 12BIT SAR 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:141
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
The MAX1240ACSA+ from Maxim Integrated is a low-power, 12-bit successive-approximation analog-to-digital converter (ADC) with internal 2.5V reference, 73ksps throughput, 7.5µs conversion time, and SPI/QSPI/MICROWIRE-compatible 3-wire serial interface - designed for precision data acquisition in space-constrained, battery-powered sensor systems.
For engineers reviewing the MAX1240ACSA+ datasheet, MAX1240ACSA+ pinout, MAX1240ACSA+ application, or MAX1240ACSA+ equivalent, this page delivers verified electrical specs, validated SO-8 package mapping, confirmed shutdown behavior (2µA), real-world timing constraints (tACQ = 1.5µs, tCONV = 7.5µs), and accurate alternative part comparisons for remote sensing and portable instrumentation designs.
Technical Context
The MAX1240ACSA+ integrates a track/hold amplifier with 1.5µs acquisition time and a 12-bit SAR core using an internal capacitive DAC referenced to its trimmed 2.5V on-chip voltage source. It operates from a single +2.7V to +3.6V supply and delivers ±0.5 LSB INL and 70dB SINAD at 10kHz input.
Its 3-wire serial interface uses unipolar MSB-first output format with end-of-conversion (EOC) signaling via DOUT high transition, supports up to 2.1MHz SCLK, and requires no external hold capacitor. Shutdown mode reduces supply current to 2µA while preserving state for fast wake-up.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Resolution | 12-bit - delivers 4096 discrete digital codes across full-scale range |
| Sampling Rate | 73ksps - supports real-time capture of signals up to ~36.5kHz Nyquist bandwidth |
| INL | ±0.5 LSB - ensures monotonicity and <0.012% full-scale linearity error |
| Supply Voltage | +2.7V to +3.6V - compatible with single-cell Li-ion and 3.3V logic rails |
| Power Consumption | 37mW at 73ksps (VDD = 3V) - enables multi-hour operation in portable data loggers |
| Reference | Internal 2.5V ±30ppm/°C - eliminates external reference component and layout area |
| Aperture Jitter | <50ps - preserves SNR in undersampling applications up to 2.25MHz small-signal BW |
Pinout & Package
MAX1240ACSA+ is housed in an 8-pin SO (Small Outline) package with standard JEDEC MO-153 footprint, 1.27mm pitch, and gull-wing leads suitable for reflow assembly.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VDD (Pin 1) | Positive supply input | Accepts +2.7V to +3.6V; powers analog/digital sections and internal reference |
| AIN (Pin 2) | Analog input | 0V to VREF (2.5V) unipolar range; input capacitance 16pF; protected to GND–0.3V/VDD+0.3V |
| SHDN (Pin 3) | Three-level shutdown control | Pull low → 2µA shutdown; leave open → disables internal reference; pull high → enables reference |
| REF (Pin 4) | Reference node | 2.5V output (MAX1240 only); bypass with 4.7µF for stability; 18kΩ min DC impedance |
| GND (Pin 5) | Analog/digital ground | Single-point star ground connection required; separates analog and digital return paths |
| DOUT (Pin 6) | Serial data output | Three-state, MSB-first, EOC signaled by rising edge; transitions on SCLK falling edge |
| CS (Pin 7) | Active-low chip select | Falling edge initiates conversion; high → places DOUT in high-impedance state |
| SCLK (Pin 8) | Serial clock input | Drives data readout up to 2.1MHz; duty cycle unrestricted if ≥200ns per phase |
Key Features
| Feature | Design Value |
|---|---|
| Single-supply operation | Operates from +2.7V to +3.6V - eliminates dual-rail design complexity in portable systems |
| Integrated track/hold | 1.5µs acquisition time with no external hold capacitor - simplifies analog front-end design |
| Low-power shutdown | 2µA quiescent current in shutdown - extends battery life between sampling intervals |
| SPI/QSPI/MICROWIRE compatibility | Direct interface to microcontroller I/O ports without level-shifting or protocol translation |
| On-chip 2.5V reference | Trimmed to ±0.5 LSB gain error over temperature - removes calibration dependency on external references |
| Small 8-pin SO package | 5.0mm × 4.0mm footprint - fits high-density PCB layouts in handheld and IoT sensor nodes |
Applications
| Battery-Powered Data Loggers | Isolated Industrial Sensors |
|---|---|
|
Use Scenario: Continuous voltage/current monitoring in field-deployed environmental sensors powered by coin-cell or Li-SOCl₂ batteries. IC Role / Device Role / Timing Role: Primary ADC digitizing transducer outputs at 1–10ksps with precise timing control via CS-triggered conversions. Use Value: 2µA shutdown current and 37mW active power enable >1-year operation on a single CR2032 cell at 1s sampling interval. |
Use Scenario: Signal conditioning in DIN-rail mounted temperature/pressure transmitters with galvanic isolation barriers. IC Role / Device Role / Timing Role: Isolated-side ADC converting analog sensor outputs into serial digital data for optocoupler or digital isolator transmission. Use Value: Internal 2.5V reference eliminates need for isolated reference supply, reducing BOM count and creepage/clearance layout constraints. |
| Portable Medical Instrumentation | Process Control Loop Monitoring |
|
Use Scenario: Analog front-end in handheld ECG or pulse oximeter devices requiring low noise, compact size, and long battery runtime. IC Role / Device Role / Timing Role: High-fidelity signal digitizer capturing bio-potential waveforms with 70dB SINAD and minimal aperture jitter. Use Value: 1.5µs track/hold acquisition and <50ps aperture jitter preserve waveform integrity for clinical-grade diagnostics. |
Use Scenario: Local analog input module in PLC I/O racks measuring 4–20mA loop signals or thermocouple outputs. IC Role / Device Role / Timing Role: Precision ADC interfacing with op-amp signal conditioners and microcontroller-based control logic. Use Value: ±0.5 LSB INL and ±1 LSB DNL ensure accurate process variable representation within 0.012% full-scale error tolerance. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar 12-bit serial ADC applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ADS7822U | 2.7V–5.25V supply; no internal reference; 200ksps; 8-pin SOIC; 1.25µs acquisition | Requires external reference and higher supply headroom; better speed but higher power (1.2mW @ 200ksps) | Select when higher throughput and wider supply range outweigh reference integration needs |
| MAX11100ASA+ | 12-bit, 1MSPS, internal 4.096V ref, 10-pin µMAX; 1.5µs acquisition; 3.0V–5.25V supply | Higher speed and resolution stability, but larger package and incompatible pinout | Choose for faster sampling in non-size-constrained industrial controllers where 4.096V reference aligns with system scaling |
Compared with ADS7822U and MAX11100ASA+, the MAX1240ACSA+ offers optimal trade-off of ultra-low shutdown current (2µA), integrated 2.5V reference, and SO-8 footprint - making it uniquely suited for long-life, space-limited, single-supply sensor nodes where reference simplicity and standby efficiency are critical.
Availability
MAX1240ACSA+ is available at Aetrix Electronics and suitable for battery-powered data loggers, isolated industrial sensors, portable medical instrumentation, and process control loop monitoring requiring stable component supply and long-term manufacturability.
Supply support for MAX1240ACSA+ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Maxim Integrated (now part of Analog Devices) is a semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, automotive, and communications markets.
The MAX1240ACSA+ belongs to Maxim's precision low-power ADC product line, engineered specifically for remote sensing, portable instrumentation, and energy-constrained data acquisition systems demanding accuracy, small size, and minimal quiescent power.
FAQ
What is the maximum sampling rate of the MAX1240ACSA+?
The MAX1240ACSA+ achieves a maximum sampling rate of 73ksps at full 12-bit resolution with VDD = 3V and fSCLK = 2.1MHz. This throughput is sustained across its operating temperature range (0°C to +70°C) and enables digitization of signals with up to ~36.5kHz Nyquist bandwidth. The device maintains specified AC performance including 70dB SINAD and ±0.5 LSB INL at this rate. Lower rates reduce power consumption proportionally - e.g., 1ksps draws just 66µW in MAX1241 variants, though MAX1240ACSA+ consumes ~3.7µW at that rate.
Does the MAX1240ACSA+ require an external reference voltage?
No, the MAX1240ACSA+ does not require an external reference voltage because it integrates a factory-trimmed 2.5V internal reference with ±30ppm/°C temperature coefficient and ±0.5 LSB gain error over temperature. The REF pin outputs this 2.5V reference and must be bypassed with a 4.7µF capacitor for stability. External reference use is optional and enabled only by leaving SHDN unconnected - in which case the internal reference is disabled and REF becomes an input accepting 1.0V to VDD.
How does the shutdown mode function on the MAX1240ACSA+?
The MAX1240ACSA+ enters shutdown mode when the SHDN pin is pulled low, reducing supply current to 2µA (typical) while retaining configuration state. Pulling SHDN high enables the internal 2.5V reference; leaving SHDN unconnected disables it, allowing external reference use. Wake-up time depends on shutdown duration due to 4.7µF REF capacitor discharge - ranging from ~4µs after brief shutdown to several milliseconds after extended periods. Conversion may begin immediately after wake-up completes.
Which microcontroller interfaces are compatible with the MAX1240ACSA+ serial port?
The MAX1240ACSA+ 3-wire serial interface is fully compatible with SPI, QSPI, and MICROWIRE protocols. It requires CPOL = 0 and CPHA = 0 configuration, supports up to 2.1MHz SCLK, and outputs MSB-first unipolar data with end-of-conversion signaled by DOUT rising edge. No level shifting is needed for 3.3V microcontrollers, and direct connection to GPIO-controlled CS/SCLK/DOUT lines suffices - eliminating protocol translation hardware or firmware overhead in Cortex-M0/M3 or PIC MCU designs.
What is the analog input voltage range supported by the MAX1240ACSA+?
The MAX1240ACSA+ accepts analog input voltages from 0V to VREF (2.5V) in unipolar mode when using its internal reference. Input protection diodes allow safe operation from GND–0.3V to VDD+0.3V, but accurate conversion requires limiting AIN to within 50mV of the supply rails - i.e., 0V to 2.55V with VDD = 3.6V. The device's input capacitance is 16pF, and source impedances below 1kΩ have negligible impact on AC performance; higher impedances require external 0.01µF input capacitance to maintain acquisition integrity.
MAX1240ACSA+ Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Number of Bits:
- 12
- Sampling Rate (Per Second):
- 73k
- Number of Inputs:
- 1
- Input Type:
- Single Ended
- Data Interface:
- SPI
- Configuration:
- S/H-ADC
- Ratio - S/H:ADC:
- 1:1
- Number of A/D Converters:
- 1
- Architecture:
- SAR
- Reference Type:
- External, Internal
- Voltage - Supply, Analog:
- 2.7V ~ 3.6V
- Voltage - Supply, Digital:
- 2.7V ~ 3.6V
- Features:
- -
- Operating Temperature:
- 0°C ~ 70°C
- Supplier Device Package:
- 8-SOIC
- Mounting Type:
- Surface Mount
- Grade:
- -
- Qualification:
- -
MAX1240ACSA+ FAQ
1.How can I place an order for MAX1240ACSA+ through Aetrix?
Please submit a Request for Quotation (RFQ) for MAX1240ACSA+ on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for MAX1240ACSA+ reliable?
The price and inventory of MAX1240ACSA+ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MAX1240ACSA+ is usually 5 days.
3.What payment methods are accepted for MAX1240ACSA+?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MAX1240ACSA+ transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MAX1240ACSA+?
MAX1240ACSA+ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MAX1240ACSA+ order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for MAX1240ACSA+?
For technical support, including MAX1240ACSA+ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MAX1240ACSA+ requirements.
6.How does Aetrix verify that MAX1240ACSA+ is sourced from the original manufacturer or authorized distributors?
All MAX1240ACSA+ products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that MAX1240ACSA+ meets industry standards.
7.What is the process for return or replacement of MAX1240ACSA+?
All MAX1240ACSA+ units undergo pre-shipment inspection (PSI). If there is an issue with MAX1240ACSA+, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The MAX1240ACSA+ part is unused and in its original packaging.
Return procedure for MAX1240ACSA+:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MAX1240ACSA+ Tags
-
ADC081C021CIMKX/NOPB
Texas Instruments
-
MCP3021A5T-E/OT
Microchip Technology
-
TLA2024IRUGR
Texas Instruments
-
MCP3221A5T-E/OT
Microchip Technology
-
MCP3221A5T-I/OT
Microchip Technology
-
MCP3221A4T-E/OT
Microchip Technology
-
MCP3221A6T-E/OT
Microchip Technology
-
MCP3221A0T-E/OT
Microchip Technology
-
MCP3221A1T-E/OT
Microchip Technology
-
ADC121S021CIMFX/NOPB
Texas Instruments
-
MCP3001-I/MS
Microchip Technology
-
MCP3001-I/SN
Microchip Technology
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
