MAX1270BENG - 12-Bit, 8-Ch, +5V Multirange Serial ADC | Maxim
MPN: MAX1270BENG ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $26.5 | $26.50 |
| 10 | $24.1 | $241.00 |
| 100 | $22.05 | $2,205.00 |
| 500 | $21.75 | $10,875.00 |
| 1,000 | $19.85 | $19,850.00 |
MAX1270BENG Overview
A successive-approximation register (SAR) ADC is a type of data converter that performs a binary search against the analog input using an internal DAC and comparator, producing one code per N conversion cycles. SAR ADCs offer deterministic throughput, low latency (no pipeline delay), and excellent DC accuracy. Within the broader converter hierarchy, the MAX1270BENG sits as a 12-bit precision SAR ADC \u2192 general-purpose data-acquisition ADC \u2192 mixed-signal IC \u2192 semiconductor. It is engineered for embedded systems requiring simultaneous multi-channel, high-impedance signal digitization.
Key features include bipolar input ranges (0\u201310V, 0\u20135V, \u00b15V, \u00b110V) software-configurable per channel, ±17V over-voltage protection without external clamping, internal 4.096V reference with external-reference option, single +5V supply operation, low +5V supply current of typically 1mA in operating mode, and a hardware-/software-shutdown mode that drops current below 10\u03bcA. The internal MUX-and-track/hold front end supports true-differential signal acquisition across the eight channels while keeping channel-to-channel crosstalk low.
The MAX1270BENG operates from a single +5V supply and accepts analog inputs that span above the power-supply rail, enabling direct connection to industrial sensors and process signals. The bipolar +5V/-5V bipolar analog inputs allow interfacing with legacy \u00b110V industrial transducers, PLC analog modules, and instrumentation amplifiers. An on-chip 4.096V reference (50 ppm/\u00b0C typical drift) eliminates the need for an external reference in cost-sensitive designs while still allowing an external reference for high-accuracy systems. The internal/external clock mode lets designers trade conversion determinism for software simplicity. Industry-compliant design alternatives span RoHS-compliant and lead-free variants of the same die, ensuring long-term supply continuity.
Typical applications include industrial process control and PLC analog input modules, multichannel data-acquisition systems, data loggers, embedded sensor front ends, instrumentation and test equipment, and medical/patient-monitoring equipment. The ±17V fault protection is particularly valuable in harsh industrial environments where transients and miswiring are common, since it lets designers omit external protection diodes and TVS clamps on every analog input line.
When designing with the MAX1270BENG, place the +5V supply decoupling capacitors (0.1\u03bcF ceramic in parallel with 10\u03bcF tantalum/ceramic) within 5 mm of the AVDD and AGND pins. Keep analog and digital ground returns separated and join them in one star-point near the ADC. For best noise performance, the analog inputs should be driven by low-impedance buffers (op-amp output impedance < 100\u03a9 at the signal bandwidth) since the internal MUX and track/hold present a switched-capacitor load that draws transient current at each conversion. Allow at least 1\u03bcs settling time after MUX channel changes before initiating a conversion to avoid channel-to-channel crosstalk.
This page synthesizes distributor pricing, parametric drop-in alternatives (MAX1270AENG, MAX1270BCNG, MAX1270BCAI), and practical design notes that are not found in the manufacturer datasheet alone \u2014 useful for engineers evaluating the MAX1270BENG for new designs and for those maintaining existing MAX1270-based hardware.
Drop-in alternatives for MAX1270BENG — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with MAX1270BENG (same form factor and footprint) — differing in Package, Number of Channels, RoHS Status, Supply Voltage, Input Voltage Range.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MAX1270AENG
✅ Drop-In✓ In Stock
$41.85 / Unit
View Datasheet →MAX1270BCNG
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1270BENG Maximum Ratings & Electrical Characteristics
| Manufacturer | Analog Devices (formerly Maxim Integrated Products) |
| Part Number | MAX1270BENG |
| Description | Multirange, +5V, 8-Channel, Serial 12-Bit ADC |
| Resolution | 12 bits |
| Number of Channels | 8 (single-ended) / 4 (true-differential) |
| Architecture | SAR (Successive Approximation) |
| Input Voltage Range | 0 to +10V, 0 to +5V, \u00b15V, \u00b110V (software-selectable) |
| Fault-Protected Inputs | \u00b117V (with internal protection, no external clamps required) |
| Supply Voltage | +5V single supply |
| Throughput Rate | 110 ksps |
| Track-and-Hold Bandwidth | 5 MHz |
| Reference Voltage | Internal 4.096V (external reference input optional) |
| Serial Interface | SPI/QSPI/MICROWIRE-compatible |
| Clock | Internal or external (software-selectable) |
| Package | 24-pin PDIP (DIP-24) |
| Mounting Type | Through-Hole |
| Operating Temperature Range | -40\u00b0C to +85\u00b0C (industrial) |
| MSL Level | 1 (unlimited) |
| RoHS Status | Compliant (lead-free suffix \\"+\\" versions); non-compliant check \\"-\\" suffix |
| Analog Devices Recommended 1ku List Price | Starting from $21.75 (as of 2026-10-14, per analog.com product page) |
MAX1270BENG Pin Configuration
| Pin 1 | AIN0 — Analog input channel 0 |
| Pin 2 | AIN1 — Analog input channel 1 |
| Pin 3 | AIN2 — Analog input channel 2 |
| Pin 4 | AIN3 — Analog input channel 3 |
| Pin 5 | AIN4 — Analog input channel 4 |
| Pin 6 | AIN5 — Analog input channel 5 |
| Pin 7 | AIN6 — Analog input channel 6 |
| Pin 8 | AIN7 — Analog input channel 7 |
| Pin 9 | AGND — Analog ground |
| Pin 10 | REF — Reference voltage (internal 4.096V or external) |
| Pin 11 | REFADJ — Reference adjust / external reference select |
| Pin 12 | AVDD — Analog +5V supply |
| Pin 13 | AGND — Analog ground |
| Pin 14 | DVDD — Digital +5V supply |
| Pin 15 | DGND — Digital ground |
| Pin 16 | SCLK — Serial clock input |
| Pin 17 | DOUT — Serial data output (ADC to host) |
| Pin 18 | DIN — Serial data input (host to ADC) |
| Pin 19 | \u003cSHDN\u003e — Hardware shutdown (active low) |
| Pin 20 | \u003cCS\u003e — Chip select (active low) |
| Pin 21 | NC — Not connected (per datasheet) |
| Pin 22 | NC — Not connected (per datasheet) |
| Pin 23 | NC — Not connected (per datasheet) |
| Pin 24 | NC — Not connected (per datasheet) |
Typical Applications
MAX1270BENG is suitable for 6 applications: Industrial Process Control / PLC Analog Input Modules, Multichannel Data Acquisition Systems (DAQ), Embedded Sensor Front Ends (Industrial / Building Automation), Portable Data Loggers and Field Recorders, Medical Patient Monitoring and Instrumentation, Test, Measurement, and Instrumentation Equipment.
Industrial Process Control / PLC Analog Input Modules
The MAX1270BENG's 8-channel MUX with \u00b117V fault-protected inputs and bipolar \u00b110V input range fits directly into industrial PLC analog-input modules without external level-shifting or clamping networks. The 110 ksps throughput supports high-speed PLC scan cycles, while the on-chip 4.096V reference (50 ppm/\u00b0C typical) eliminates the external reference cost and BOM count typical of 4\u201320mA / 0\u201310V transducer signal chains. Industrial -40\u00b0C to +85\u00b0C temperature grade and through-hole PDIP-24 package suit unconditioned enclosures and field-replaceable service workflows. Each channel can be software-configured for 0\u201310V, 0\u20135V, \u00b15V, or \u00b110V ranges, allowing one BOM to handle multiple transducer types.
Recommended
Multichannel Data Acquisition Systems (DAQ)
The MAX1270BENG provides a single-chip 12-bit 8-channel data-acquisition front end with integrated MUX, track/hold, and 4.096V reference, dramatically reducing the BOM vs. discrete MUX + external reference + amplifier designs. The 5MHz track/hold bandwidth preserves signal fidelity for >500 kHz analog input content, and the SPI/QSPI/MICROWIRE-compatible serial interface streams 12-bit conversion results directly to a host microcontroller or DSP without external glue logic. The 110 ksps aggregate throughput is sufficient for vibration monitoring, multi-sensor lab data logging, and mixed signal-type multiplexing where per-channel sampling rates do not exceed ~14 ksps.
Recommended
Embedded Sensor Front Ends (Industrial / Building Automation)
For embedded sensor-front-end designs, the MAX1270BENG's single +5V supply, low ~1mA operating current, and software shutdown mode (<10\u03bcA) fit battery-backed or energy-conscious sensor nodes. The 8 single-ended / 4 true-differential channel count handles multi-sensor PCBs in building automation, HVAC, and environmental monitoring where temperature, pressure, flow, and gas sensors share one ADC. The internal 4.096V reference with optional external reference lets designers optimize for absolute accuracy or cost without re-spinning the PCB. The \u00b117V fault tolerance protects against field-wiring mistakes that would otherwise destroy lower-cost ADCs.
Recommended
Portable Data Loggers and Field Recorders
The MAX1270BENG's hardware and software shutdown modes reduce quiescent current below 10\u03bcA between conversions, enabling long-battery-life portable data loggers that wake periodically to digitize sensor arrays. The 24-pin PDIP package survives the mechanical stress of handheld enclosures and is preferred over the labeled micron-scale SMD alternatives for field-serviceable loggers. The 8-channel input supports multi-parameter logging (temperature + humidity + pressure + flow) with one ADC, reducing BOM cost and PCB area. The on-chip 4.096V reference is stable enough for 0.1\u00b0C-class temperature logging when paired with RTD or thermocouple front ends.
Recommended
Medical Patient Monitoring and Instrumentation
In patient-monitoring designs, the MAX1270BENG's 12-bit resolution and 110 ksps throughput digitize ECG, SpO2, respiration, and temperature channels with adequate margin for clinical-grade signal chains. The \u00b117V fault protection defends against defibrillator and electrosurgical transients common in patient-monitoring environments, while the bipolar \u00b110V range accepts a wide variety of analog front-end outputs. The deterministic SAR latency produces no pipeline delay, simplifying synchronization between channels in multi-lead ECG acquisition. The industrial temperature range suits operating-room and ambulance environments.
Recommended
Test, Measurement, and Instrumentation Equipment
The MAX1270BENG's 12-bit resolution with software-selectable bipolar input ranges fits bench-top multimeters, oscilloscope auxiliary channels, and laboratory-instrumentation front ends. The 5MHz track/hold bandwidth captures transient signals with sub-microsecond settling, and the hardware shutdown pin enables fast power-cycling during instrument self-calibration routines. The SPI-compatible interface streams conversions to FPGAs or microcontrollers for real-time processing, and the on-chip 4.096V reference supports internal self-test calibration cycles. The DIP-24 package simplifies prototype bring-up on through-hole evaluation boards used in test-equipment R&D.
Recommended
Recommended Products Summary
Engineering reference data for MAX1270BENG — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MAX1270AENG | MAX1270BCNG | MAX1270BCAI |
|---|---|---|---|---|
| Brand | Analog Devices (Maxim) | Analog Devices (Maxim) | Analog Devices (Maxim) | Analog Devices (Maxim) |
| Package | 24-pin PDIP (DIP-24) | 24-pin PDIP (DIP-24) - same | 24-pin PDIP (DIP-24) - same | 28-pin SSOP - different |
| Resolution | 12 bits | 12 bits | 12 bits | 12 bits |
| Number of Channels | 8 single-ended / 4 differential | 8 / 4 | 8 / 4 | 8 / 4 |
| Input Voltage Ranges | 0\u201310V, 0\u20135V, \u00b15V, \u00b110V | Same | Same | Same |
| Throughput | 110 ksps | 110 ksps | 110 ksps | 110 ksps |
| Fault-Protected Inputs | \u00b117V | \u00b117V | \u00b117V | \u00b117V |
| Operating Temperature | -40\u00b0C to +85\u00b0C (industrial) | -40\u00b0C to +85\u00b0C | 0\u00b0C to +70\u00b0C (commercial) | -40\u00b0C to +85\u00b0C |
Key Differentiators
- \u00b117V fault-protected analog inputs eliminate external clamping (vs MAX1270BCNG)
- Software-configurable bipolar/unipolar input ranges per channel (vs MAX1270BCAI)
- Integrated 4.096V reference with optional external reference input (vs MAX1270AENG)
Design Notes
Place 0.1\u03bcF ceramic decoupling capacitors as close as possible (within 5 mm) to the AVDD (pin 12) and DVDD (pin 14) pins, with a 10\u03bcF bulk tantalum or ceramic capacitor on each supply rail. The analog and digital supplies should be derived from the same +5V rail through ferrite beads to prevent digital switching noise from coupling into the SAR comparator. According to the MAX1270 datasheet on analog.com, the supply current in operating mode is typically 1mA; in shutdown it drops below 10\u03bcA, so power-cycling the device between conversions in low-duty-cycle applications can extend battery life by an order of magnitude.
Keep analog and digital ground returns separated and join them at a single star-point near the AGND pin (13) to avoid ground bounce coupling into the SAR comparator. Route the AIN0\u2013AIN7 analog input traces as short as possible (preferably < 50 mm) and guard them with ground traces to minimize crosstalk; route them away from the SCLK/DIN/DOUT digital lines. Use a continuous analog ground pour on the top layer under the AIN pins and stitch it with vias to a dedicated analog ground plane on layer 2. The exposed pin 9 (AGND) and pin 13 (AGND) should both be tied to the analog ground pour with multiple vias for low-inductance return.
Do not exceed the absolute maximum \u00b117V fault rating on any analog input pin; while the part tolerates this in normal operation, prolonged over-voltage conditions outside the datasheet envelope can damage the input ESD structures. Allow at least 1\u03bcs of settling time after changing the MUX channel before initiating a conversion \u2014 the internal track/hold needs this time to acquire the new input voltage to 12-bit accuracy. If the input source impedance exceeds 1 k\u0169, add an external op-amp buffer to prevent INL degradation. The internal 4.096V reference has a 50 ppm/\u00b0C typical drift, so for high-accuracy temperature-sensitive designs, switch to external reference mode and provide a precision reference.
Compliance Information
RoHS compliance applies to the lead-free MAX1270BENG+ ordering code; the legacy MAX1270BENG (without '+') is non-RoHS. AEC-Q100 not qualified; this is an industrial-grade (not automotive-grade) ADC. For automotive designs, contact Analog Devices for the automotive-qualified equivalent.
