MAX198AEAI - 12-Bit 6-Ch DAS w/ Fault Protection | Maxim Integrated
MPN: MAX198AEAI ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $38.5 | $38.50 |
| 10 | $34.2 | $342.00 |
| 100 | $28.9 | $2,890.00 |
| 500 | $23.45 | $11,725.00 |
| 1,000 | $19.8 | $19,800.00 |
MAX198AEAI Overview
A Data Acquisition System (DAS) is a mixed-signal integrated circuit that combines an analog multiplexer, sample-and-hold, ADC, voltage reference, and digital interface into a single package. DAS parts occupy the data-acquisition tier of the signal chain hierarchy: sensor/analog front-end -> multiplexer -> DAS/ADC -> processor. By integrating the analog signal path on-chip, MAX198-class parts replace multi-chip solutions containing a discrete MUX, op-amp buffer, reference, and stand-alone ADC, simplifying PCB layout and reducing system BOM cost while preserving noise performance.
Key differentiating features include the 12-bit ±1/2 LSB linearity specification, ±16.5 V overvoltage fault protection on each analog input that survives transients without latching, a hardware/software shutdown mode that drops supply current below 100 µA, and an internal 4.096 V reference that can also be overdriven by an external source. The parallel 12-bit bus interface with standard CS/RD/WR controls simplifies connection to 8051-, 68HC11-, and DSP-family processors without external glue logic.
Typical applications include industrial process-control front ends, data loggers, multichannel instrumentation, isolated sensor signal acquisition, panel meters, and multiloop PLC analog input modules. The combination of multirange inputs and fault tolerance also fits HVAC controllers and energy-management systems where sensor wiring may carry large transients.
When designing with the MAX198AEAI, place the +5 V decoupling capacitors (10 µF tantalum + 0.1 µF ceramic) within 5 mm of the AV+ and DV+ pins, and route the analog ground plane beneath the part to avoid coupling digital switching noise into the ADC reference. The internal reference output (REF) requires a 4.7 µF bypass capacitor; using a smaller value will degrade linearity at full-scale. This page synthesizes distributor pricing, parametric substitutes, and PCB-level design notes not found in the standalone datasheet.
Drop-in alternatives for MAX198AEAI — 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 MAX198AEAI (same form factor and footprint) — differing in Number of Channels, Package, Internal Reference, Resolution, Fault Protection.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MAX198AEAI+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX198BCAI
✅ Drop-In✓ In Stock
$16.95 / Unit
View Datasheet →MAX198ACAI+T
✅ Drop-In📋 Reference alternative (not in catalog)
MAX198BEAI+T
✅ Drop-In📋 Reference alternative (not in catalog)
MAX196ACAI
✅ Drop-In✓ In Stock
$35.12 / Unit
View Datasheet →MAX198AEAI Maximum Ratings & Electrical Characteristics
| Resolution | 12 bit |
| Number of Channels | 6 single-ended / 3 differential (analog input MUX) |
| Sampling Rate | 100 kSPS |
| Supply Voltage | +5 V (single supply) |
| Input Voltage Ranges | 0 to +5 V, 0 to +10 V, ±5 V, ±10 V, 0 to VREF, 0 to 2xVREF, ±VREF, ±2xVREF (software-selectable) |
| Internal Reference | 4.096 V |
| Fault Protection | ±16.5 V on analog inputs (without latch-up) |
| Linearity | ±1/2 LSB (max) |
| Interface | 12-bit parallel (CS, RD, WR control) |
| Shutdown Current | below 100 µA (software/hardware) |
| Package | 28-SSOP (5.30 mm) |
| Mounting Type | Surface Mount |
| Lead Free | Lead Free |
| RoHS Status | RoHS Compliant |
MAX198AEAI 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 | REF — Reference Output / ADC Reference |
| Pin 8 | REFADJ — Reference Adjust |
| Pin 9 | AGND — Analog Ground |
| Pin 10 | AV+ — Analog +5 V Supply |
| Pin 11 | DV+ — Digital +5 V Supply |
| Pin 12 | DGND — Digital Ground |
| Pin 13 | HBEN — High-Byte Enable |
| Pin 14 | INT — Conversion End / Interrupt Output |
| Pin 15 | RD — Read Strobe (active low) |
| Pin 16 | WR — Write / Convert Start (active low) |
| Pin 17 | CS — Chip Select (active low) |
| Pin 18 | D11 — Data Bit 11 (MSB) |
| Pin 19 | D10 — Data Bit 10 |
| Pin 20 | D9 — Data Bit 9 |
| Pin 21 | D8 — Data Bit 8 |
| Pin 22 | D7 — Data Bit 7 |
| Pin 23 | D6 — Data Bit 6 |
| Pin 24 | D5 — Data Bit 5 |
| Pin 25 | D4 — Data Bit 4 |
| Pin 26 | D3 — Data Bit 3 |
| Pin 27 | D2 — Data Bit 2 |
| Pin 28 | D1 — Data Bit 1 (LSB) |
Typical Applications
MAX198AEAI is suitable for 6 applications: Industrial Process Control Front End, Multichannel Data Logger, HVAC Environmental Controller, Multimeter and Panel Meter Front End, PLC Analog Input Module, Energy Management System Sensor Interface.
Industrial Process Control Front End
The MAX198AEAI fits industrial process-control front ends because of its six single-ended input channels, ±16.5 V analog input fault protection, and 100 kSPS aggregate throughput from a single +5 V supply. In a typical PLC analog-input module each channel is scaled to a 4-20 mA current-loop or 0-10 V transducer; the MAX198AEAI tolerates wiring transients and over-range voltages without damage. The internal 4.096 V reference simplifies calibration to engineering units. Compared with a discrete MUX-plus-ADC solution the MAX198AEAI eliminates three components, reducing BOM and PCB area. Eight software-selectable input ranges let one part cover multiple transducer types.
Recommended
Multichannel Data Logger
The MAX198AEAI's six input channels and 12-bit resolution make it ideal for compact multi-channel data loggers measuring temperature, pressure, and flow. The 100 kSPS throughput is adequate for sampling several slow sensors sequentially, while the internal sample-and-hold eliminates external components. In a typical portable data-logger design the MAX198AEAI is paired with an 8051-family MCU that controls channel selection via the parallel bus and stores results to serial EEPROM. Built-in fault protection preserves the ADC during field wiring errors, a common issue with thermocouple-based logging.
Recommended
HVAC Environmental Controller
The MAX198AEAI's six analog inputs and ±16.5 V fault protection are well-matched to HVAC environmental controllers that monitor multiple temperature, humidity, and pressure sensors sharing long cable runs. The fault tolerance prevents ADC damage when actuator wiring shorts sensor lines, while the eight software-selectable input ranges simplify interface with both 0-10 V and 4-20 mA transducers. Hardware/software shutdown drops supply current below 100 µA for battery-backed operation during power loss. Industrial-grade operating temperature and SSOP-28 package suit panel-mount designs.
Recommended
Multimeter and Panel Meter Front End
Digital multimeters and panel meters leverage the MAX198AEAI's six ranges of input scaling (with eight software-selectable span options) to cover DC voltage, current, and sensor readout without external signal conditioning. The 12-bit ±1/2 LSB linearity is sufficient for 3-1/2 digit panel meters, while the 100 kSPS throughput supports fast update rates. Built-in fault protection to ±16.5 V lets the meter survive accidental overload conditions during field service. The 28-SSOP package fits compact handheld designs.
Recommended
PLC Analog Input Module
Programmable Logic Controller (PLC) analog input modules often use the MAX198AEAI for its multi-range capability and ±16.5 V fault tolerance on every analog input. Six channels per chip minimize PCB area in 8- or 16-channel modules; multiple MAX198AEAI parts can be cascaded through the parallel bus using CS decoding. The internal 4.096 V reference provides ratiometric measurements when paired with ratiometric sensors such as strain gauges. Single +5 V supply operation simplifies isolated DC-DC converter design.
Recommended
Energy Management System Sensor Interface
Energy Management Systems (EMS) monitor current, voltage, and temperature across power distribution panels; the MAX198AEAI provides six isolated or non-isolated analog inputs with the ±16.5 V fault protection needed to survive inductive transients from motor loads and contactor coils. The 100 kSPS throughput captures one-cycle AC waveforms when sampled with appropriate synchronization. The 28-SSOP industrial-grade package and +5 V supply simplify integration into legacy EMS designs that already use Maxim DAS parts.
Recommended
Recommended Products Summary
Engineering reference data for MAX198AEAI — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MAX198AEAI+ | MAX198BCAI | MAX198ACAI+T | MAX198BEAI+T | MAX196ACAI |
|---|---|---|---|---|---|---|
| Brand | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated |
| Package | 28-SSOP | 28-SSOP (same) | 28-SSOP (same) | 28-SSOP (same) | 28-SSOP (same) | 28-SSOP (same) |
| Resolution | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit |
| Number of Channels | 6 | 6 | 6 | 6 | 6 | 6 |
| Sampling Rate | 100 kSPS | 100 kSPS | 100 kSPS | 100 kSPS | 100 kSPS | 100 kSPS |
| Linearity | ±1/2 LSB | ±1/2 LSB | ±1/2 LSB (B-grade, tighter) | ±1/2 LSB | ±1/2 LSB (B-grade) | ±1/2 LSB |
| Input Ranges | 0-VREF, ±VREF, 0-2xVREF, ±2xVREF (MAX198 set) | Same MAX198 set | Same MAX198 set | Same MAX198 set | Same MAX198 set | ±5/±10 V, 0-5/0-10 V (MAX196 set) |
| Fault Protection | ±16.5 V | ±16.5 V | ±16.5 V | ±16.5 V | ±16.5 V | ±16.5 V |
| Supply Voltage | +5 V single | +5 V single | +5 V single | +5 V single | +5 V single | +5 V single |
| Lifecycle Status | Obsolete | Obsolete (legacy stock) | Obsolete (legacy stock) | Obsolete (legacy stock) | Obsolete (legacy stock) | Obsolete (legacy stock) |
Key Differentiators
- Six analog input channels with integrated fault protection (vs MAX187CEWE (single-channel 12-bit ADC))
- Eight software-selectable input ranges (vs MAX174AEPI (single fixed range))
- Parallel 12-bit bus interface (vs MAX1270ACNG (serial SPI interface))
Design Notes
The MAX198AEAI requires both analog and digital +5 V supplies. Place a 10 µF tantalum + 0.1 µF ceramic decoupling pair within 5 mm of the AV+ pin and a 0.1 µF ceramic within 5 mm of the DV+ pin. Separate analog and digital ground planes that join only at the AGND/DGND pins to avoid digital switching noise coupling into the ADC reference. Estimated supply current: ~5 mA typical at 100 kSPS operation; enable shutdown mode for battery-backed designs to drop below 100 µA.
The internal 4.096 V reference output at the REF pin requires a minimum 4.7 µF bypass capacitor (tantalum or ceramic) to maintain linearity. Place this capacitor as close to the REF pin as possible. The REFADJ pin sets the reference voltage; do not leave it floating. If using an external reference, drive REFADJ with an op-amp buffer or precision reference DAC. Maintain a continuous analog ground plane beneath the MAX198AEAI to avoid ground-bounce errors.
The MAX198AEAI's parallel 12-bit bus can couple noise into the analog section if not properly terminated. Route the digital bus traces (D0-D11, RD, WR, CS, INT) away from the analog input traces and the REF pin. Place a 4.7 kΩ pull-up on the INT line if not actively driven by the host MCU. Use a chip-select decoder for cascaded MAX198AEAI parts rather than tying WR/RD/CS together when multiple DAS devices share the bus.
Avoid configuring input ranges above the +5 V supply rail for unipolar mode; for ±10 V bipolar ranges the device uses internal resistive dividers but the ±16.5 V fault tolerance is the absolute maximum, not a normal operating voltage. Note: the MAX198AEAI differs from the MAX196AEAI in input range selection bits; reuse of MAX196 firmware on a MAX198 board will produce incorrect readings. Do not exceed 100 kSPS acquisition rate - the internal track-and-hold requires setup time between conversions.
Compliance Information
The MAX198AEAI without '+' suffix is the original lead-bearing variant; the RoHS-compliant drop-in is MAX198AEAI+. Not AEC-Q100 qualified (industrial grade only). Reach compliant per Maxim product declarations.
