MAX187BC/D - 12-Bit Serial SAR ADC, +5V, Die Form | Maxim Integrated
MPN: MAX187BC/D ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $14.5 | $14.50 |
| 10 | $13.1 | $131.00 |
| 100 | $11.2 | $1,120.00 |
| 500 | $9.85 | $4,925.00 |
| 1,000 | $8.4 | $8,400.00 |
MAX187BC/D Overview
A successive-approximation register (SAR) ADC is a converter architecture that performs a binary search against the analog input using an internal DAC and comparator, producing one bit per clock cycle. SAR ADCs are favored for medium-speed (kHz to low-MHz), low-latency, deterministic conversion because there is no pipeline delay - the result is valid exactly N+1 clock cycles after the CONVST edge. In the broader data-converter hierarchy, SAR ADCs sit between flash converters (fastest, highest power) and sigma-delta converters (highest resolution, lowest bandwidth); the MAX187BC/D targets instrumentation and process-control bandwidths.
Key specifications include 12-bit resolution, 75 kHz sampling rate, +/-1/2 LSB integral nonlinearity (A-grade), 1.5 mA operating supply current, 2 uA shutdown current, and 7.5 mW typical power dissipation. The internal 4.096V buffered reference provides a stable, low-impedance reference without an external buffer, simplifying BOM and PCB area. The serial interface runs to SPI/QSPI/MICROWIRE peripherals on microcontrollers and DSPs without glue logic.
Architecture-wise, the MAX187BC/D combines a capacitive DAC, a high-bandwidth track/hold, and a precision on-chip reference with factory trimming. The internal clock eliminates the need for an external ADC clock source, and the hardware SHUTDOWN pin reduces quiescent current to microampere levels for battery-powered designs.
Typical applications include portable instrumentation, process-control data acquisition, pen-digitizers, battery-powered data loggers, isolated sensor front ends, and precision weighing scales where small PCB footprint and low power matter. The die format suits hybrid microcircuits and chip-on-board modules. Industrial temperature grades (C suffix, 0C to +70C) cover commercial environments.
A primary design consideration with die-format parts is packaging and wire-bonding: the MAX187BC/D requires assembly onto a substrate or package with gold or aluminum wire bonds and hermetic/encapsulation protection. For PCB designs, designers typically select the pin-equivalent MAX187BCPA+ (PDIP-8) or MAX187BCWE+ (SOIC-16 wide). Designers should provide adequate input bypass (0.1 uF close to VDD) and a low-impedance analog ground return to preserve 12-bit linearity.
This page synthesizes distributor pricing, drop-in package alternatives, and die-level design guidance that goes beyond the manufacturer datasheet. Engineers evaluating MAX187BC/D should treat the bare-die option as a hybrid-assembly component and weigh the BOM savings of internal reference and clock against the assembly complexity.
Drop-in alternatives for MAX187BC/D — 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 MAX187BC/D (same form factor and footprint) — differing in Architecture, Sampling Rate, Shutdown Current, Supply Voltage, Track/Hold Acquisition Time.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MAX187BCPA+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX187BCWE+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX187BEPA
✅ Drop-In✓ In Stock
$9.85 / Unit
View Datasheet →MAX187ACPA+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX187AEPA+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX187CCWE+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX187BC/D Maximum Ratings & Electrical Characteristics
| Resolution | 12 bits |
| Architecture | Successive Approximation (SAR) |
| Number of Channels | 1 |
| Input Voltage Range | 0 V to 5 V |
| Supply Voltage | +5 V single supply |
| Sampling Rate | 75 kHz |
| Conversion Time | 8.5 us |
| Track/Hold Acquisition Time | 1.5 us |
| Integral Nonlinearity (MAX187A) | +/-1/2 LSB (max) |
| Internal Reference | 4.096 V buffered |
| Operating Supply Current | 1.5 mA (typ) |
| Shutdown Current | 2 uA (typ) |
| Power Dissipation | 7.5 mW (typ), 10 uW shutdown |
| Digital Interface | 3-wire SPI/QSPI/MICROWIRE-compatible serial |
| Package Type | DIE (unpackaged, 8 terminals, no-lead) |
| Temperature Grade | Commercial (C suffix: 0C to +70C) |
| Internal Clock | Yes (on-chip) |
| RoHS Status | Compliant (per Maxim/ADI product page) |
MAX187BC/D Pin Configuration
| Pin 1 | VREF — Internal 4.096 V reference bypass (decouple to AGND) |
| Pin 2 | AIN — Analog input (0 V to 5 V) |
| Pin 3 | AGND — Analog ground |
| Pin 4 | SHDN — Shutdown input (active low) |
| Pin 5 | DOUT — Serial data output |
| Pin 6 | SSTRB — Serial strobe output |
| Pin 7 | CS — Chip select (active low) |
| Pin 8 | VDD — +5 V supply |
Typical Applications
MAX187BC/D is suitable for 6 applications: Portable Battery-Powered Data Loggers, Process Control Data Acquisition, Precision Weighing Scales and Pen Digitizers, Isolated Sensor Front Ends, Hybrid Microcircuits and MCM Modules, Medical Instrumentation Front Ends.
Portable Battery-Powered Data Loggers
The MAX187BC/D is well suited to portable, battery-powered data-logger front ends where the bare-die format saves PCB area and the internal 4.096 V reference eliminates an external reference IC. With 1.5 mA operating current and 2 uA shutdown current (controlled via the SHUTDOWN pin), the part delivers roughly 7.5 mW active and 10 uW standby - critical for multi-month battery life on 9V or lithium-thionyl cells. Its 12-bit resolution and 1.22 mV LSB step at 0-5 V input accommodate thermocouple, RTD, and 4-20 mA current-loop signal conditioning. Wire-bonded into a hybrid module, the ADC pairs naturally with low-power microcontrollers via the 3-wire SPI/QSPI/MICROWIRE-compatible interface, simplifying firmware-driven duty cycling between acquisitions and sleep intervals.
Recommended
Process Control Data Acquisition
In industrial process-control and SCADA front ends, the MAX187BC/D provides 75 kHz sampling and 12-bit resolution sufficient for 0-5 V transducer signals from pressure, flow, and level transmitters. The internal track/hold with 1.5 us acquisition handles multiplexed multi-channel scanning when paired with an external analog mux, while the SAR architecture delivers deterministic, no-pipeline-delay conversion - ideal for control loops where latency must be predictable. The 3-wire SPI interface daisy-chains to a host PLC or microcontroller without glue logic, and the 4.096 V internal reference scales the LSB to 1 mV per code, convenient for 0-5 V industrial sensors. The C-grade commercial temperature range (0C to +70C) is adequate for cabinet-mounted equipment; for outdoor installations, designers should specify MAX187BE/MAX187AE extended temperature variants.
Recommended
Precision Weighing Scales and Pen Digitizers
Pen-digitizer tablets and precision weighing-scale front ends require low-noise 12-bit conversion with deterministic latency, both hallmarks of the MAX187BC/D SAR architecture. The internal track/hold captures fast strain-gauge bridge transients without droop, while the 4.096 V internal reference provides 1 mV/LSB scaling that aligns naturally with bridge outputs amplified to 0-4 V full scale. The bare-die format enables direct integration into the load-cell housing or pen-tip hybrid module, eliminating long analog traces that would otherwise inject noise. SPI/QSPI/MICROWIRE compatibility allows the host microcontroller to read conversion results at the host bus speed, simplifying firmware and freeing CPU cycles for calibration, filtering, and tare-weight compensation.
Recommended
Isolated Sensor Front Ends
Isolated 4-20 mA current-loop sensors and shunt-based current monitors benefit from the MAX187BC/D's small die footprint, which fits inside the isolation barrier housing alongside an isolated DC/DC converter and digital isolator. The 75 kHz sample rate captures 50/60 Hz-line-derived signals with margin for digital filtering, while the 1.5 mA operating current is sustainable from the isolated side's small bias supply. Internal 4.096 V reference eliminates a precision reference on the hot side, reducing BOM and improving long-term stability. Designers should route the SPI signals through a digital isolator (such as Maxim's MAX14850 or MAX14130) to bring conversion results back to the host microcontroller without ground loops.
Recommended
Hybrid Microcircuits and MCM Modules
The MAX187BC/D is purpose-built for hybrid microcircuit and multi-chip module (MCM) integration. Aerospace, defense, and downhole oil-drilling applications routinely use bare-die ADCs to minimize PCB area and to operate over wider thermal and vibration ranges than plastic packages tolerate. The 12-bit SAR core, internal reference, and on-chip clock minimize the surrounding component count - critical when every bond pad adds assembly cost. Designers wire-bond the die onto a ceramic substrate with gold or aluminum interconnects, then encapsulate for hermeticity. The C-grade commercial temperature range is suitable for many industrial and aerospace subsystems; for military -55C to +125C operation, designers should evaluate the MAX187AMRG/883B or similar Mil-Std-883 processed variants.
Recommended
Medical Instrumentation Front Ends
Patient-monitoring devices such as infusion pumps, blood-pressure cuffs, and pulse oximeters require 12-bit resolution and low standby current, both delivered by the MAX187BC/D. The internal 4.096 V reference scales the LSB to 1 mV/code for direct interfacing with amplified sensor outputs (pressure, SpO2 photodiode current-to-voltage), and the 1.5 mA operating current keeps thermal dissipation inside the patient-contact housing within safe limits. The 2 uA shutdown mode enables sleep between measurements, extending battery life on wearable monitors. Bare-die assembly supports compact, single-board designs that integrate the ADC with the sensor signal chain. Designers should validate IEC 60601 EMI/ESD margins and consider the MAX187BE extended-temperature grade for non-clinical environments.
Recommended
Recommended Products Summary
Engineering reference data for MAX187BC/D — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MAX187BCPA+ | MAX187BCWE+ | MAX187BEPA | MAX187ACPA+ | MAX187AEPA+ | MAX187CCWE+ |
|---|---|---|---|---|---|---|---|
| Brand | Maxim Integrated (ADI) | Maxim Integrated (ADI) | Maxim Integrated (ADI) | Maxim Integrated (ADI) | Maxim Integrated (ADI) | Maxim Integrated (ADI) | Maxim Integrated (ADI) |
| Package | DIE (8 terminals, no-lead) | PDIP-8 - same die | SOIC-16 Wide - same die | PDIP-8 - same die | PDIP-8 - same die | PDIP-8 - same die | SOIC-16 Wide - same die |
| Resolution | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits |
| Sampling Rate | 75 kHz | 75 kHz | 75 kHz | 75 kHz | 75 kHz | 75 kHz | 75 kHz |
| INL (max) | +/-1 LSB (B-grade) | +/-1 LSB | +/-1 LSB | +/-1 LSB | +/-1/2 LSB | +/-1/2 LSB | +/-1 LSB |
| Temperature Grade | Commercial (0C to +70C) | Commercial (0C to +70C) | Commercial (0C to +70C) | Extended (-40C to +85C) | Commercial (0C to +70C) | Extended (-40C to +85C) | Commercial (0C to +70C) |
| Internal Reference | 4.096 V buffered | 4.096 V buffered | 4.096 V buffered | 4.096 V buffered | 4.096 V buffered | 4.096 V buffered | 4.096 V buffered |
| Interface | 3-wire SPI/QSPI/MICROWIRE | 3-wire SPI/QSPI/MICROWIRE | 3-wire SPI/QSPI/MICROWIRE | 3-wire SPI/QSPI/MICROWIRE | 3-wire SPI/QSPI/MICROWIRE | 3-wire SPI/QSPI/MICROWIRE | 3-wire SPI/QSPI/MICROWIRE |
Key Differentiators
- Bare-die form factor for hybrid/MCM integration (vs MAX187BCPA+ (PDIP-8))
- B-grade INL specification with same internal reference and clock as A-grade (vs MAX187ACPA+ (A-grade))
- Commercial temperature grade optimized for indoor industrial use (vs MAX187BEPA (extended temperature))
- Pin-equivalent to MAX187BCPA+ (PDIP-8) for design reuse (vs MAX187BCPA+ (PDIP-8))
Design Notes
Estimated: When wire-bonding MAX187BC/D onto a substrate, keep bond-wire length below 2 mm to minimize inductance on VDD and VREF. The internal 4.096 V reference relies on low-impedance decoupling (0.1 uF ceramic placed within 1 mm of the bond pad) to maintain 12-bit linearity. Long bond wires on VDD or AIN introduce ringing that can degrade INL by 1-2 LSB.
When converting a MAX187BC/D design to a PCB-mountable equivalent, lay out the analog and digital grounds as a star-ground configuration with the AGND bond pad as the single tie point. The MAX187BCPA+ and MAX187BCWE+ pin-compatible package versions include separate AGND and DGND pins - use a ferrite bead or 0 ohm resistor to bridge them under the IC. Avoid routing the SPI clock (SCLK) parallel to analog traces to prevent digital coupling into the analog input.
The MAX187BC/D consumes 7.5 mW typical in continuous conversion mode. In a hybrid microcircuit, this becomes part of the substrate thermal budget. For sealed ceramic packages, ensure the substrate's thermal resistance is low enough to keep the die junction below 70C at the maximum rated ambient. C-grade commercial parts are specified 0C to +70C; for higher ambient temperatures, select the B/E or A/E extended-temperature variants (MAX187BEPA or MAX187AEPA+).
The MAX187BC/D uses a 3-wire SPI interface with CS, SCLK, and DOUT plus a SSTRB strobe. Per the Maxim datasheet, SSTRB goes low when the conversion starts and rises to indicate the MSB is valid on DOUT. Designers should sample SSTRB on the rising edge to gate SPI reads, avoiding the need for precise software timing. Add a 10 kohm pull-up on SSTRB and DOUT if the host bus is long (>50 mm) to preserve signal integrity.
Use the SHUTDOWN pin aggressively in battery-powered designs. Driving SHUTDN low reduces quiescent current from 1.5 mA to 2 uA. Wake-up time is approximately 10 us per the Maxim datasheet, so a duty-cycled pattern of 1 ms active + 99 ms shutdown can drop average supply current to under 20 uA for low-frequency data-logger sampling, dramatically extending battery life.
Compliance Information
RoHS and REACH compliance per Maxim/ADI product declaration. Not AEC-Q100 qualified (automotive); for AEC-Q100 designs, consider MAX16914 or similar. Bare-die parts carry RoHS compliance at the wafer level - the hybrid-assembly BOM (substrate, wire bonds, encapsulation) must also be RoHS compliant for the finished module.
