MAX1068AEEG+ - 14-Bit, 200ksps, 8-Ch SAR ADC | Maxim Integrated
MPN: MAX1068AEEG+ ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $11.85 | $11.85 |
| 10 | $10.78 | $107.80 |
| 100 | $9.62 | $962.00 |
| 500 | $8.55 | $4,275.00 |
| 1,000 | $7.48 | $7,480.00 |
MAX1068AEEG+ Overview
An SAR ADC is a successive-approximation register analog-to-digital converter that uses a binary-search algorithm and an internal capacitive DAC to convert an analog input into a digital code, one bit per clock cycle. The MAX1068AEEG+ belongs to the broader category of data converters (ADC -> SAR ADC -> precision ADC -> mixed-signal IC), serving as the bridge between analog sensors and digital processors in embedded systems. Its 8 single-ended or 4 pseudo-differential analog input channels and integrated front-end reference make it well suited for multiplexed data-acquisition systems.
Key features include true 14-bit resolution with no missing codes, 200 ksps throughput, an internal 4.096 V reference, an internal 2.4576 MHz oscillator, automatic power-down between conversions to reduce quiescent current, and an SPI/QSPI/MICROWIRE-compatible serial interface. The device operates from a single +5 V analog supply and a +5 V digital supply, providing excellent noise immunity in mixed-signal environments. The integrated input multiplexer supports 8 single-ended or 4 pseudo-differential input channels, scanned sequentially with on-chip track-and-hold.
Architecturally, the MAX1068AEEG+ combines a charge-redistribution capacitive DAC, a high-bandwidth input track-and-hold, a precision bandgap reference, and a digital serial engine in a single die. The integrated +4.096 V reference and reference buffer eliminate the need for an external precision reference and decoupling network, simplifying the analog front-end and reducing board area. Automatic power-down between conversions drops supply current to a few microamps, making the part attractive for battery-powered or power-cycled measurement systems.
Typical applications include multichannel data-acquisition systems, industrial process control, portable instrumentation, patient monitoring and medical diagnostics, system monitoring in servers and base stations, and precision sensor interfaces. Designers commonly pair the MAX1068AEEG+ with low-noise op-amps for input buffering and with digital isolators for galvanically isolated industrial links.
When designing with this ADC, provide separate analog and digital ground planes joined at a single point near the device, decouple both AVDD and DVDD with 10 uF tantalum and 0.1 uF ceramic capacitors placed as close as possible to the pins, and drive unused analog inputs to a defined mid-supply voltage to prevent crosstalk. The internal reference requires no external bypass, but keeping REF away from noisy digital traces preserves 14-bit linearity.
This page synthesizes distributor pricing, drop-in same-brand and cross-brand alternatives, and practical design notes not consolidated in the manufacturer datasheet, providing an engineering decision aid beyond the standard product page.
Drop-in alternatives for MAX1068AEEG+ — 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 MAX1068AEEG+ (same form factor and footprint) — differing in Number of Channels, Resolution, Operating Temperature, Architecture, Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MAX1068ACEG+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1068AEEG+T
✅ Drop-In✓ In Stock
$6.12 / Unit
View Datasheet →MAX1011CEG+
✅ Drop-In✓ In Stock
$5.05 / Unit
View Datasheet →MAX1068AEEG+ Maximum Ratings & Electrical Characteristics
| Resolution | 14 bits |
| Sample Rate | 200 ksps |
| Architecture | SAR (Successive Approximation) |
| Number of Input Channels | 8 single-ended / 4 pseudo-differential |
| Input Type | Single-ended / pseudo-differential |
| Analog Supply Voltage | +4.75 V to +5.25 V |
| Digital Supply Voltage | +4.75 V to +5.25 V |
| Internal Reference Voltage | +4.096 V |
| Internal Oscillator | 2.4576 MHz |
| Serial Interface | SPI / QSPI / MICROWIRE-compatible |
| Operating Temperature | 0 C to +70 C (commercial) |
| Package Type | QSOP-24 (0.150 inch, 0.250 inch pitch, MO-137AE) |
| Number of Pins | 24 |
| Mounting Type | Surface Mount |
| Terminal Form | Gull Wing |
| Power-Down Mode | Automatic between conversions |
| RoHS Status | Compliant |
MAX1068AEEG+ Pin Configuration
| Pin 1 | CH0 — Analog input channel 0 |
| Pin 2 | CH1 — Analog input channel 1 |
| Pin 3 | CH2 — Analog input channel 2 |
| Pin 4 | CH3 — Analog input channel 3 |
| Pin 5 | CH4 — Analog input channel 4 |
| Pin 6 | CH5 — Analog input channel 5 |
| Pin 7 | CH6 — Analog input channel 6 |
| Pin 8 | CH7 — Analog input channel 7 |
| Pin 9 | AGND — Analog ground |
| Pin 10 | REF — Reference voltage output (4.096 V) |
| Pin 11 | AVDD — Analog supply voltage (+5 V) |
| Pin 12 | AGND — Analog ground |
| Pin 13 | SCLK — Serial clock input |
| Pin 14 | DIN — Serial data input |
| Pin 15 | DOUT — Serial data output |
| Pin 16 | SSTRB — Serial strobe output |
| Pin 17 | CS — Chip select (active low) |
| Pin 18 | DVDD — Digital supply voltage (+5 V) |
| Pin 19 | DGND — Digital ground |
| Pin 20 | OSC — Oscillator select / external clock input |
| Pin 21 | PD — Power-down input (active high) |
| Pin 22 | NC — Not connected (per datasheet) |
| Pin 23 | NC — Not connected (per datasheet) |
| Pin 24 | NC — Not connected (per datasheet) |
Typical Applications
MAX1068AEEG+ is suitable for 6 applications: Multichannel Data Acquisition Systems, Industrial Process Control and Sensor Interfaces, Portable Instrumentation and Battery-Powered Measurement, Patient Monitoring and Medical Diagnostics, System Monitoring in Servers and Base Stations, Precision Sensor Interfaces for Strain Gauges and Thermocouples.
Multichannel Data Acquisition Systems
The MAX1068AEEG+ fits multichannel data-acquisition systems because its 8 single-ended or 4 pseudo-differential input channels, 14-bit resolution, and 200 ksps throughput allow simultaneous scanning of multiple analog sensors in a single ADC. Its integrated +4.096 V reference eliminates the need for an external precision reference, and the automatic power-down between conversions drops quiescent current to microamp levels, ideal for power-cycled DAQ front-ends. Designers typically place a 10 uF tantalum and 0.1 uF ceramic decoupling pair within 5 mm of AVDD/DVDD, and route the analog input traces over a continuous ground plane to preserve 14-bit linearity. The QSOP-24 footprint enables high channel density on compact DAQ boards.
Recommended
Industrial Process Control and Sensor Interfaces
The MAX1068AEEG+ serves industrial process control by digitizing 4-20 mA current-loop or 0-10 V voltage outputs from PLCs, temperature sensors, and pressure transducers. Its 14-bit resolution yields approximately 0.6 mV LSB at 10 V full scale, sufficient for process control loop trimming, while the 8-channel input multiplexer supports multiple sensor nodes on a single ADC. The +5 V single-supply operation and integrated reference reduce analog front-end complexity, and the QSOP-24 package is compatible with crowded PLC backplanes. Industrial designers should pair the ADC with isolation amplifiers such as the ISO124 for galvanically isolated field links.
Recommended
Portable Instrumentation and Battery-Powered Measurement
The MAX1068AEEG+ is well matched to portable instrumentation because its automatic power-down mode between conversions drops supply current to a few microamps, dramatically extending battery life in handheld multimeters, dataloggers, and field test gear. The 14-bit resolution at 200 ksps covers most portable measurement bandwidths, and the 8 single-ended input channels allow direct connection to thermocouples, strain gauges, and other transducers through small signal-conditioning op-amps. The QSOP-24 surface-mount package suits handheld product enclosures, and the SPI-compatible serial interface allows direct connection to low-power microcontrollers without parallel bus pins.
Recommended
Patient Monitoring and Medical Diagnostics
The MAX1068AEEG+ supports patient monitoring equipment by digitizing ECG, EEG, SpO2, and temperature sensor signals with 14-bit resolution. Its 8-channel input multiplexer allows simultaneous sampling of multiple vital signs on a single ADC, reducing bill-of-materials cost in bedside monitors and portable pulse oximeters. The integrated +4.096 V reference simplifies medical analog front-ends, and the SPI-compatible serial interface enables straightforward isolation barrier implementation with digital isolators. Designers should still add a low-noise op-amp buffer (e.g., MAX4250) in front of the ADC to maintain 14-bit linearity in low-level ECG channels.
Recommended
System Monitoring in Servers and Base Stations
The MAX1068AEEG+ is used in server and base-station monitoring boards to digitize power supply voltages, temperatures, and fan tachometer signals on the management plane. Its 8 input channels allow a single ADC to monitor multiple board rails (3.3 V, 5 V, 12 V) and several temperature sensors, reducing the management-MCU pin count. The 14-bit resolution is more than adequate for supply voltage margining, and the SPI-compatible interface allows multiple MAX1068AEEG+ devices to share a single bus via chip-select lines. The QSOP-24 package fits standard server monitoring daughter cards, and the integrated reference reduces external component count.
Recommended
Precision Sensor Interfaces for Strain Gauges and Thermocouples
The MAX1068AEEG+ serves as the digitization stage for precision sensor interfaces, digitizing strain-gauge bridge outputs, thermocouple pairs, and RTD signals at 14-bit resolution. Its 4 pseudo-differential input mode rejects common-mode noise on long sensor cable runs, and the integrated track-and-hold preserves signal integrity for wide-bandwidth transducer signals. The 200 ksps throughput is sufficient for vibration and acoustic emission monitoring, and the QSOP-24 footprint allows compact instrumentation amplifier front-ends. Designers should follow the manufacturer recommended low-pass RC filter on the analog inputs to limit RF pickup in industrial environments.
Recommended
Recommended Products Summary
Engineering reference data for MAX1068AEEG+ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MAX1068ACEG+ | MAX1068AEEG+T | MAX1067BCEE | MAX1011CEG+ | MAX1240BCSA+ |
|---|---|---|---|---|---|---|
| Brand | Analog Devices (Maxim Integrated) | Analog Devices (Maxim Integrated) | Analog Devices (Maxim Integrated) | Analog Devices (Maxim Integrated) | Analog Devices (Maxim Integrated) | Analog Devices (Maxim Integrated) |
| Package | QSOP-24 (0.150 inch, MO-137AE) | QSOP-24 - same | QSOP-24 - same | QSOP-16 - smaller | QSOP-24 - same | SOIC-8 - different |
| Resolution | 14 bits | 14 bits | 14 bits | 12 bits | 14 bits | 12 bits |
| Architecture | SAR | SAR | SAR | SAR | SAR | SAR |
| Serial Interface | SPI / QSPI / MICROWIRE | SPI / QSPI / MICROWIRE | SPI / QSPI / MICROWIRE | SPI / QSPI / MICROWIRE | SPI-compatible | SPI / QSPI / MICROWIRE |
| Operating Temperature | 0 C to +70 C (commercial) | 0 C to +70 C | 0 C to +70 C | 0 C to +70 C | 0 C to +70 C | 0 C to +70 C |
Key Differentiators
- Highest pin-and-spec compatible drop-in within the MAX1068 family (vs MAX1068ACEG+)
- Higher channel count and resolution versus the MAX1067BCEE (vs MAX1067BCEE)
- Tape-and-reel packaging option for high-volume production (vs MAX1068AEEG+T)
Design Notes
The MAX1068AEEG+ requires separate AVDD and DVDD supplies, both nominally +5 V. Place a 10 uF tantalum and a 0.1 uF ceramic decoupling capacitor as close as possible to each supply pin (within 5 mm), and connect AGND and DGND at a single star point near the ADC. According to the Maxim datasheet, the internal reference requires only a 10 uF bypass on REF; inadequate decoupling on DVDD can couple digital switching noise into the analog front-end, degrading 14-bit linearity.
Route all analog input traces over a continuous ground plane and keep them away from the digital serial interface traces (SCLK, DOUT, DIN) and the oscillator pin. The QSOP-24 pinout groups analog pins on one side of the package and digital pins on the other, which simplifies layout, but the pinout diagram in the manufacturer datasheet should still be followed to preserve the AGND/DGND split. The reference pin (REF) should be treated as an analog signal trace, not a supply rail, to avoid injecting digital ground noise into the reference buffer.
To preserve 14-bit linearity, drive the analog inputs with low-impedance op-amp buffers (such as the MAX4250 or MAX4230) rather than high-impedance sensor sources. According to the Maxim datasheet, the analog input track-and-hold has a finite acquisition time, so the source impedance should be kept below 1 kohm at 200 ksps; a 100 ohm series resistor at each input combined with the ADC's internal sampling capacitor forms a low-pass filter that limits broadband RF pickup in industrial environments.
Common pitfalls include driving unused analog inputs to AGND instead of a defined mid-supply voltage (which can cause crosstalk on active channels), and using a shared ground pour for both analog and digital return currents (which can inject switching noise into the analog front-end). Another common mistake is leaving the PD pin floating; it should be tied to DGND through a 100 kohm pulldown to keep the ADC enabled by default, and toggled high only when power-down is desired to drop supply current to microamp levels between conversions.
Compliance Information
RoHS and REACH compliant per Maxim Integrated product environmental certification; lead-free and halogen-free per Maxim datasheet ordering information. Not AEC-Q100 qualified (commercial-grade part); for automotive applications, the MAX1068 family does not include a Q1 automotive variant.
