MAX154AEWG - 8-Bit 4Ch 2.5us ADC w/ Reference | Maxim Integrated
MPN: MAX154AEWG ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $18.45 | $18.45 |
| 10 | $16.5 | $165.00 |
| 100 | $13.85 | $1,385.00 |
| 500 | $11.95 | $5,975.00 |
| 1,000 | $10.45 | $10,450.00 |
MAX154AEWG Overview
An analog-to-digital converter (ADC) is a mixed-signal integrated circuit that samples a continuous analog voltage and converts it into a discrete digital code, typically N-bit binary. SAR ADCs use a binary-search successive-approximation algorithm with an internal DAC and comparator, achieving an excellent balance of speed, resolution, and power consumption for data acquisition, instrumentation, and process-control applications. The MAX154 family sits in the hierarchy: SAR ADC -> ADC -> data converter -> mixed-signal IC -> semiconductor.
Key features include four single-ended analog inputs (the pin-compatible MAX158 offers eight), a 2.5V internal bandgap reference (5 V external reference also accepted), ratiometric operation, and an on-chip track/hold. The MAX154AEWG provides 1/2 LSB integral nonlinearity and ±1 LSB total unadjusted error, with low-power CMOS design drawing only a few mW during continuous conversion.
The MAX154AEWG uses a standard SAR architecture with internal clock generation, allowing simple microprocessor interface through standard CS, RD, and WR control lines. It connects directly to most 8-bit parallel buses without external glue logic. The wide input voltage range (single +5 V supply) and ratiometric capability make it suitable for both absolute and proportional measurements.
Typical applications include data acquisition systems, process control, digital signal processing front-ends, multiplexed sensor monitoring, and portable instruments. The four-channel input makes it ideal for low-channel-count multi-signal monitoring without an external MUX.
When designing with this device, observe the recommended 0.1 uF decoupling capacitor on VDD, keep analog and digital ground planes separated, and ensure analog inputs stay within the specified input range (0 V to VREF or 0 V to 5 V).
This page synthesizes distributor pricing, drop-in same-package alternatives, and practical design notes not found on the manufacturer datasheet, giving engineers a single reference for sourcing, comparison, and design-in.
Drop-in alternatives for MAX154AEWG — 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 MAX154AEWG (same form factor and footprint) — differing in Number of Input Channels, Operating Temperature, Package, Resolution, Integral Nonlinearity (INL).
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MAX154AEWG+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX154BEWG+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX154BCWG+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX158
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MAX154AEWG Maximum Ratings & Electrical Characteristics
| Resolution | 8 bit |
| Number of Input Channels | 4 |
| Conversion Architecture | SAR (Successive Approximation) |
| Conversion Time per Channel | 2.5 us (typical) |
| Internal Reference | 2.5 V (bandgap) |
| Supply Voltage (VDD) | +5 V (single supply) |
| Analog Input Range | 0 V to VREF (ratiometric mode) |
| Integral Nonlinearity (INL) | 1/2 LSB (max) |
| Total Unadjusted Error | 1 LSB (max) |
| Operating Temperature | -40 C to +85 C (industrial) |
| Temperature Grade | Industrial |
| Package | 24-SOIC (Wide, 7.5 mm body width) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| Lead-Free | Yes |
MAX154AEWG Pin Configuration
| Pin 1 | AIN1 — Analog input channel 1 |
| Pin 2 | AIN2 — Analog input channel 2 |
| Pin 3 | AIN3 — Analog input channel 3 |
| Pin 4 | AIN4 — Analog input channel 4 |
| Pin 5 | AGND — Analog ground |
| Pin 6 | VDD — +5 V supply |
| Pin 7 | DGND — Digital ground |
| Pin 8 | REF — Reference input/output (2.5 V internal) |
| Pin 9 | DB0 — Digital output bit 0 (LSB) |
| Pin 10 | DB1 — Digital output bit 1 |
| Pin 11 | DB2 — Digital output bit 2 |
| Pin 12 | DB3 — Digital output bit 3 |
| Pin 13 | DB4 — Digital output bit 4 |
| Pin 14 | DB5 — Digital output bit 5 |
| Pin 15 | DB6 — Digital output bit 6 |
| Pin 16 | DB7 — Digital output bit 7 (MSB) |
| Pin 17 | A0 — Channel address input 0 |
| Pin 18 | A1 — Channel address input 1 |
| Pin 19 | CS — Chip select (active low) |
| Pin 20 | RD — Read strobe (active low) |
| Pin 21 | WR — Write/conversion start (active low) |
| Pin 22 | INT — Interrupt / end-of-conversion (active low) |
| Pin 23 | NC — Not connected (per datasheet) |
| Pin 24 | NC — Not connected (per datasheet) |
Typical Applications
MAX154AEWG is suitable for 6 applications: Multi-Channel Data Acquisition Systems, Process Control and Industrial Monitoring, Portable Battery-Powered Instruments, Sensor Array Multiplexing and Signal Conditioning, Digital Panel Meter and Display Front-Ends, Embedded Control and Microcontroller Interface Boards.
Multi-Channel Data Acquisition Systems
The MAX154AEWG's 4 single-ended analog inputs and 2.5 us conversion time suit it to multi-channel data acquisition front-ends where several sensors must be sampled sequentially by a single ADC. With its integrated 2.5 V reference and SAR architecture, the part delivers 8-bit accuracy at up to ~400 kSPS aggregate throughput, eliminating external MUX and reference components. Place 0.1 uF decoupling on VDD close to the IC and route analog/digital grounds separately. Compared to discrete ADC plus external reference designs, the MAX154 reduces BOM count and PCB area while preserving upgrade path to the pin-compatible MAX158 (8 channels).
Recommended
Process Control and Industrial Monitoring
The MAX154AEWG's -40 C to +85 C industrial temperature rating and +5 V single-supply operation suit it to process-control front-ends monitoring temperature, pressure, and flow sensor outputs. The integrated 2.5 V bandgap reference simplifies calibration by anchoring absolute readings to an on-chip source, while the 4-channel input handles multiple sensor taps from a single ADC. Its parallel 8-bit interface connects directly to legacy 8051 and PIC microcontrollers without glue logic. In distributed control nodes, this ADC trades 12-bit precision for lower cost and simpler firmware, fitting tightly-bounded measurement tasks.
Recommended
Portable Battery-Powered Instruments
The MAX154AEWG's single +5 V supply, CMOS low-power design, and integrated 2.5 V reference suit portable handheld instruments such as digital multimeters, environmental loggers, and medical point-of-care devices. Drawing only a few mW during conversion, it extends battery life while still providing 8-bit resolution adequate for sensor readouts and human-readable displays. The 4-channel input accepts multiple sensors (temperature, humidity, pressure) without external multiplexing. Compared to higher-resolution ADCs, the MAX154's modest 8-bit quantization matches the dynamic range needed for many consumer-grade measurements while minimizing bill of materials.
Recommended
Sensor Array Multiplexing and Signal Conditioning
The MAX154AEWG's built-in 4-to-1 input multiplexer simplifies sensor array designs by eliminating external analog switches when reading multiple transducers through a single ADC. Combined with the integrated 2.5 V reference, it provides a complete ratiometric signal chain for bridge sensors, thermistors, and potentiometric dividers. The SAR architecture settles in 2.5 us per channel, providing adequate settling time for most sensor bandwidths. Engineers pairing it with strain gauges or RTD bridges benefit from the synchronous sampling capability and predictable aperture time, ensuring repeatable readings across the 4-channel scan sequence.
Recommended
Digital Panel Meter and Display Front-Ends
The MAX154AEWG's parallel 8-bit output bus directly drives LED segment drivers, LCD controllers, and 7-segment display decoder logic, making it well suited to digital panel meter front-ends and process-display readouts. The 2.5 us conversion speed easily exceeds the human-eye update rate for typical panel meters, while the integrated reference simplifies calibration to absolute voltage units. Four input channels allow simultaneous monitoring of multiple process variables in a single display instrument. This ADC fits cost-sensitive industrial HMI applications where 8-bit resolution is sufficient for operator-level visualization and trend display.
Recommended
Embedded Control and Microcontroller Interface Boards
The MAX154AEWG's standard CS/RD/WR parallel interface makes it an easy peripheral for legacy 8-bit microcontrollers in embedded control designs. Reading 4 analog inputs requires only three GPIO pins (CS, RD, WR plus interrupt), freeing microcontroller resources for digital I/O and communication tasks. The 2.5 us conversion time matches instruction cycles of slower MCUs, allowing polling without DMA. With its industrial temperature grade, the MAX154 suits automotive under-hood modules, HVAC controllers, and appliance boards where 8-bit precision is acceptable. The 24-SOIC package is hand-solderable for prototypes and small-batch production runs.
Recommended
Recommended Products Summary
Engineering reference data for MAX154AEWG — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MAX154AEWG+ | MAX154BEWG+ | MAX154BCWG+ | MAX158 |
|---|---|---|---|---|---|
| Brand | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated |
| Package | 24-SOIC (Wide) | 24-SOIC (Wide) - same | 24-SOIC (Wide) - same | 24-SOIC (Wide) - same | 24-SOIC (Wide) - same |
| Resolution | 8 bit | 8 bit | 8 bit | 8 bit | 8 bit |
| Input Channels | 4 | 4 | 4 | 4 | 8 (pin-compatible upgrade) |
| Conversion Time | 2.5 us | 2.5 us | 2.5 us | 2.5 us | 2.5 us |
| Internal Reference | 2.5 V | 2.5 V | 2.5 V | 2.5 V | 2.5 V |
| Temperature Grade | Industrial (-40 C to +85 C) | Industrial (-40 C to +85 C) | Commercial (0 C to +70 C) | Commercial (0 C to +70 C) | Industrial/Commercial variants |
| RoHS Compliance | No (original), + variant RoHS | Yes (RoHS-compliant) | Yes (RoHS-compliant) | Yes (RoHS-compliant) | Yes (RoHS variants available) |
Key Differentiators
- Integrated 2.5 V bandgap reference (vs MAX154AEWG+)
- Industrial temperature grade (-40 C to +85 C) (vs MAX154BEWG+)
- Pin-compatible upgrade path to MAX158 (vs MAX158 (8-channel variant))
Design Notes
Place a 0.1 uF ceramic decoupling capacitor as close as possible to the VDD pin (pin 6), ideally within 3 mm. According to the Maxim Integrated datasheet, noisy VDD rails directly degrade ADC linearity and increase conversion noise. Add a 10 uF bulk tantalum or ceramic capacitor near the IC if the VDD trace is longer than 25 mm, and keep VDD separate from high-current digital supply paths.
Maintain separate analog and digital ground planes joined at a single point under the IC's AGND/DGND pins. According to the Maxim Integrated datasheet, mixing analog and digital return currents on the same trace couples digital switching noise into the SAR comparator, reducing effective resolution. Route analog input traces away from digital bus traces, and place the REF pin bypass (typically 4.7 uF tantalum in parallel with 0.1 uF ceramic) close to pin 8.
Keep analog input traces short and guarded by a ground trace to minimize capacitive coupling from adjacent digital signals. According to the Maxim Integrated datasheet, the input capacitance is small but sampling transients during track mode can corrupt the reading if source impedance exceeds the recommended 500 ohm maximum. Add a small RC filter (10 ohm + 100 pF) at each AIN pin for noisy sensor environments, and avoid long unshielded cables connecting sensors directly to AIN inputs.
Do not apply analog inputs outside the 0 V to VREF range or above VDD, as latch-up can result. According to the Maxim Integrated datasheet, the SAR architecture holds the input sample on an internal capacitor for the full conversion; high-impedance sources or excessive source resistance degrade the held voltage and cause conversion errors. If the analog signal is unipolar but spans a small range, scale it to use the full 0-VREF swing for maximum 8-bit resolution utilization.
Compliance Information
MAX154AEWG (without + suffix) is the original lead-finished variant; for RoHS-compliant builds, choose the MAX154AEWG+ variant. Reach and conflict minerals compliance per Maxim Integrated product declaration.
