MAX191BCWG-T - 12-Bit 75ksps Sampling ADC w/ Internal Ref | Maxim
Teilenummer: MAX191BCWG-T ✗ Abgekündigt| Menge | Stückpreis | Gesamt |
|---|---|---|
| 1 | $19.75 | $19,75 |
| 10 | $17.78 | $177,80 |
| 100 | $15.8 | $1.580,00 |
| 500 | $13.83 | $6.915,00 |
| 1.000 | $11.85 | $11.850,00 |
MAX191BCWG-T Übersicht
What is an SAR ADC? A successive-approximation-register analog-to-digital converter is a class of medium-speed, medium-resolution data converter that resolves one bit per clock cycle using an internal DAC, comparator, and SAR logic. SAR ADCs sit in the hierarchy: ADC -> data converter -> data acquisition IC -> mixed-signal semiconductor. Unlike delta-sigma ADCs they offer single-cycle conversions and excellent DC accuracy, and unlike flash ADCs they consume far less silicon area, making them ideal for multiplexed industrial and instrumentation channels.
Key features of the MAX191BCWG-T include 12-bit resolution with no missing codes, an internal buried-Zener reference trimmed to within ±1.5%, a software-configurable analog input range of 0V to VREF or bipolar ±VREF, a Byte/parallel interface, and a hardware-active-low RD and CS control. The wide-body SOIC-24 package offers easy hand-soldering and straightforward prototype rework while still being surface-mountable for production. The internal reference removes the need for an external reference IC, saving PCB area and BOM cost in space-constrained designs.
The MAX191 is built on a BiCMOS process that combines bipolar precision (for the bandgap reference and comparator) with CMOS logic for low-power digital control. This mixed-signal architecture gives the part a true DC accuracy better than ±1 LSB INL and DNL and a SINAD of approximately 70 dB, suitable for instrumentation, process control, and pen-digitizer front ends. Power-down is invoked by a single serial or parallel-mode command and is hardware-assertable through the active-low shutdown pin in the WSOIC package.
Typical applications include data-logging front ends, pen-tablet digitizers, process-control analog input modules, portable instrumentation, and battery-powered data-acquisition boards. The combination of internal reference, single +5V supply operation, and low power-down current makes the part especially attractive for hand-held and remote-monitoring equipment.
When designing with this part, allocate an input RC network (typically 1 kohm + 100 pF) to limit transients at the analog input, and route the VREF decoupling capacitor (4.7 uF minimum) as close to the REF pin as possible. Verify that the bipolar/unipolar mode jumper is correctly configured before sampling; otherwise conversions will be off-scale.
This page synthesizes distributor pricing, obsolete-lifecycle sourcing guidance, same-brand replacements and cross-brand pin-to-pin ADC equivalents not found in the manufacturer datasheet alone.
Drop-in-Alternativen für MAX191BCWG-T – gleiches Gehäuse, Pin-kompatibel. Bauteile mit anderem Gehäuse, die eine PCB-Überarbeitung erfordern, sind ausgeschlossen.
Varianten dieser Serie
Modelle derselben Serie, die drop-in-kompatibel sind mit MAX191BCWG-T (gleiche Bauform und Footprint) – abweichend in Input Voltage Range, Number of Channels, Operating Temperature, Package, Resolution.
Schnellvergleichstool – Wählen Sie Alternativbauteile für den Direktvergleich:
MAX191BCWG+T
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
MAX191BCWG+
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
MAX191ACWG+T
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
MAX191AEWG+
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
MAX190BCWG+T
✅ Drop-In✓ Auf Lager
$6.15 / Stück
Datenblatt ansehen →AD7853ARZ-REEL
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
MAX191BCWG-T Grenzwerte & elektrische Eigenschaften
| Auflösung | 12 bit |
| Abtastrate | 75 ksps |
| Architecture | SAR (Successive Approximation) |
| Number of Channels | 1 single-ended input |
| Input Type | Single-ended, unipolar or bipolar |
| Eingangsspannungsbereich | 0 V to VREF (unipolar) or -VREF to +VREF (bipolar) |
| Internal Reference Voltage | 4.096 V (typ, ±1.5%) |
| Supply Voltage (VDD) | +5 V (±5%) |
| Supply Current (operating) | 3 mA (typ) |
| Schnittstelle | Byte-wide parallel (8-bit bus) |
| INL (typical) | ±1/2 LSB (max) |
| DNL (typical) | ±1 LSB (max) |
| Gehäuse | WSOIC-24 (300 mil wide-body SOIC) |
| Betriebstemperatur | 0 °C to +70 °C (commercial grade) |
| Montageart | Surface Mount |
| RoHS-Status | Non-RoHS (legacy Maxim part, see -T suffix note) |
| Power-Down Mode | Hardware and software controlled |
MAX191BCWG-T Pin-Konfiguration
| Pin 1 | VDD — +5V analog and digital supply |
| Pin 2 | AIN — Analog input (single-ended) |
| Pin 3 | REF — Internal 4.096V reference output / bypass |
| Pin 4 | AGND — Analog ground |
| Pin 5 | BIP — Bipolar mode select (low = unipolar, high = bipolar) |
| Pin 6 | SHDN — Hardware shutdown (active low) |
| Pin 7 | D7 — Data bit 7 (MSB) |
| Pin 8 | D6 — Data bit 6 |
| Pin 9 | D5 — Data bit 5 |
| Pin 10 | D4 — Data bit 4 |
| Pin 11 | DGND — Digital ground |
| Pin 12 | D3 — Data bit 3 |
| Pin 13 | D2 — Data bit 2 |
| Pin 14 | D1 — Data bit 1 |
| Pin 15 | D0 — Data bit 0 (LSB) |
| Pin 16 | CS — Chip select (active low) |
| Pin 17 | RD — Read strobe (active low) |
| Pin 18 | INT — Conversion complete interrupt (active low) |
| Pin 19 | CLK — External conversion clock input |
| Pin 20 | MODE — Serial/parallel interface mode select |
| Pin 21 | DOUT — Serial data output (when in serial mode) |
| Pin 22 | SCLK — Serial clock (when in serial mode) |
| Pin 23 | NC — Not connected (per datasheet) |
| Pin 24 | NC — Not connected (per datasheet) |
Typische Anwendungen
MAX191BCWG-T ist geeignet für 7 Anwendungs: Industrial Data-Logging Front End, Pen-Tablet Digitizer Signal Acquisition, Process-Control Analog Input Cards, Portable Hand-Held Instrumentation, Battery-Powered Remote Sensor Nodes, Legacy Industrial Automation PCB Repair, Educational Laboratory Bench Instruments.
Industrial Data-Logging Front End
The MAX191BCWG-T is well-suited to industrial data-logging front ends because it integrates a 4.096 V bandgap reference, eliminating the external reference IC and saving both PCB area and BOM cost. Its 12-bit SAR core delivers true DC accuracy better than ±1 LSB INL and DNL, which is critical for thermocouple, RTD, and 4-20 mA current-loop digitizing where 0.1% full-scale resolution is mandatory. The 75 ksps throughput is more than adequate for multiplexed analog input modules sampling multiple channels at 1 kHz each. Designers typically place the part at the analog domain boundary, fed by an input-protection RC network (1 kohm + 100 pF) to limit transient over-voltage at the AIN pin. The hardware power-down pin is asserted between scan bursts to drop quiescent current to under 10 uA, which is essential for battery-backed remote telemetry units that wake on a duty cycle.
Empfohlen
Pen-Tablet Digitizer Signal Acquisition
In pen-tablet and graphics-digitizer designs the MAX191BCWG-T converts the position-sensing analog voltages from the tablet's wire grid into 12-bit digital coordinates. The internal track/hold captures the X/Y coordinates within 1 µs of the digitizer strobe, and the parallel Byte-wide interface streams coordinates to the host processor without DMA latency. The unipolar 0-4.096 V input range matches the typical signal swing from the digitizer's analog frontend, eliminating the need for external level shifting. At 3 mA operating current the part is friendly to USB-powered tablets, and the hardware shutdown pin enables the host MCU to drop the part into <10 uA sleep when the pen is idle, extending battery life. Designers should keep the AGND and DGND pins tied at a single star point beneath the WSOIC-24 package to avoid digital noise coupling into the analog AIN input.
Empfohlen
Process-Control Analog Input Cards
Process-control analog input cards benefit from the MAX191BCWG-T's combination of 12-bit resolution, integrated reference, and bipolar ±VREF input range. The bipolar mode lets the part digitize both 4-20 mA current loops (with a sense resistor) and ±10 V industrial signals (with an input attenuator) using the same ADC, simplifying the analog front end. The WSOIC-24 package fits the standard 24-pin card outline used by many PLC analog modules, allowing direct PCB reuse. Hardware RD and CS pins allow easy connection to a parallel address-mapped bus on a microcontroller or FPGA. Designers should place a 100 ohm + 100 pF input RC network on AIN to limit charge-injection kickback from the SAR internal DAC, which is essential at the 75 ksps throughput to preserve ±1 LSB linearity.
Empfohlen
Portable Hand-Held Instrumentation
The MAX191BCWG-T is a strong fit for portable hand-held instrumentation such as digital multimeters, weigh scales, and medical point-of-care devices because of its low 3 mA operating current and integrated 4.096 V reference. The internal reference eliminates a separate precision reference IC, shrinking the analog section and reducing quiescent current by 200-500 uA, which directly translates to longer battery life. The hardware CS and RD signals simplify interface to low-pin-count microcontrollers like the MAXQ2000 or MAX32620, allowing the host to gate the ADC on demand. The WSOIC-24 package has a wide thermal pad that conducts heat away from the die during continuous 75 ksps sampling, helping the part stay within the commercial 0 °C to +70 °C operating window inside an enclosed handheld case. The 12-bit resolution provides 4096 counts, sufficient for a 3.5-digit handheld meter display with 0.05% basic accuracy.
Empfohlen
Battery-Powered Remote Sensor Nodes
Remote sensor nodes that wake periodically to sample a sensor and transmit via radio benefit from the MAX191BCWG-T's sub-10 µA power-down current and fast wake-up. Between transmissions the host MCU can assert the hardware shutdown pin to drop the ADC supply current into the single-digit µA range, preserving battery life for months or years on a single coin cell. The 12-bit resolution is adequate for temperature, humidity, and pressure sensors whose intrinsic noise floor rarely justifies more than 12 bits. The integrated 4.096 V reference removes the need for a second precision reference IC, reducing the BOM depth and saving PCB area. Engineers should pair the MAX191BCWG-T with a low-power radio such as the MAX7032 transceiver and a small microcontroller that can wake the ADC on a periodic timer. The WSOIC-24 package is hand-solderable, which simplifies prototype rework in the field.
Empfohlen
Legacy Industrial Automation PCB Repair
The MAX191BCWG-T remains valuable for repair and maintenance of legacy industrial automation PCBs that already carry the WSOIC-24 footprint from Maxim's 1990s product generation. Many PLC analog-input modules, CNC machine tool interfaces, and motor-drive feedback boards from that era used the MAX191 as the primary ADC and have been fielded for 25+ years. Repair shops and asset-management engineers need authentic replacement parts to maintain regulatory-certified production lines without requiring a full board redesign. The +T suffix part is RoHS-compliant and pin-compatible, simplifying inventory management. The 12-bit accuracy and ±1 LSB linearity is sufficient for the original 0.1% process-control specification. Replacement should be done lot-by-lot with traceability records to satisfy ISO 9001 / FDA 21 CFR Part 11 audit requirements in regulated industries.
Empfohlen
Educational Laboratory Bench Instruments
University and training-lab bench instruments are well served by the MAX191BCWG-T because the WSOIC-24 wide-body SOIC package is hand-solderable and breadboard-friendly for student lab exercises. The 12-bit resolution and 75 ksps throughput provide a teaching platform for SAR conversion theory, reference-voltage design, and parallel-bus interfacing without overwhelming student budgets. The internal 4.096 V reference is a useful teaching example of integrated bandgap design and reduces the number of supporting components students must wire. The bipolar/unipolar mode jumper demonstrates real-world ADC input-range configuration, and the hardware RD/CS pins map directly to a parallel address bus on the lab's training microcontroller. Instructors can pair the part with a MAXQ2000 or any 8051-family MCU for a full ADC teaching lab.
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Zusammenfassung der empfohlenen Produkte
Technische Referenzdaten für MAX191BCWG-T – Vergleich, Designhinweise und Compliance-Informationen.
Auswahlhilfe
Vergleich mit Alternativen
| Parameter | Dieses Produkt | MAX191BCWG+T | MAX191BCWG+ | MAX191ACWG+T | MAX191AEWG+ | MAX190BCWG+T | AD7853ARZ-REEL |
|---|---|---|---|---|---|---|---|
| Brand | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Analog Devices |
| Package | WSOIC-24 | WSOIC-24 - same | WSOIC-24 - same | WSOIC-24 - same | WSOIC-24 - same | WSOIC-24 - same | WSOIC-24 - same |
| Resolution | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit |
| Internal Reference | Yes (4.096 V) | Yes (4.096 V) | Yes (4.096 V) | Yes (4.096 V) | Yes (4.096 V) | No (external) | No (external) |
| Operating Temperature | 0 °C to +70 °C (B grade) | 0 °C to +70 °C (B grade) | 0 °C to +70 °C (B grade) | -40 °C to +85 °C (A grade) | -40 °C to +85 °C (A grade) | 0 °C to +70 °C (B grade) | -40 °C to +85 °C |
| Interface | Byte parallel | Byte parallel | Byte parallel | Byte parallel | Byte parallel | Byte parallel | Byte parallel |
| RoHS Compliance | Non-RoHS (legacy -T) | RoHS (Pb-free) | RoHS (Pb-free) | RoHS (Pb-free) | RoHS (Pb-free) | RoHS (Pb-free) | RoHS (Pb-free) |
| Lifecycle Status | Obsolete | Obsolete (same die) | Obsolete (same die) | Obsolete | Obsolete | Obsolete | Active |
Wichtigste Unterscheidungsmerkmale
- Integrated 4.096V bandgap reference eliminates external reference IC (vs. MAX190BCWG+T)
- Lower throughput for lower power consumption (vs. AD7853ARZ-REEL)
- Hardware and software power-down modes drop quiescent current below 10 µA (vs. MAX191BCWG+)
- Commercial temperature grade sufficient for indoor and bench applications (vs. MAX191ACWG+T)
Designhinweise
Per the Maxim datasheet, decouple the VDD pin with a 10 uF tantalum in parallel with a 0.1 uF ceramic placed within 1 cm of the pin. The SAR architecture draws sharp current spikes at the conversion clock edge, and insufficient decoupling will appear as ±1-2 LSB noise on the conversion result. The internal 4.096 V reference also requires its own 4.7 uF bypass capacitor placed directly at the REF pin to keep reference-noise-induced errors within ±1 LSB at 75 ksps throughput.
Tie AGND and DGND together at a single star point directly beneath the WSOIC-24 package, then route the combined ground to the system ground plane. Separating analog and digital ground planes and joining them only at the ADC star point prevents switching noise from the parallel data bus (D0-D7) from coupling into the analog AIN input. Keep the AIN trace short and surround it with a ground guard ring to minimize leakage and crosstalk from adjacent digital traces.
Add a 100 ohm series resistor plus 100 pF bypass capacitor on the AIN input to limit charge-injection kickback from the internal SAR capacitor DAC. Without this RC network, the input mux switching transient can introduce ±2 LSB errors at the start of each acquisition. The 100 ohm / 100 pF time constant (~50 ns) is well below the acquisition window at 75 ksps (~13 µs), preserving settling accuracy. Also keep the REF bypass capacitor trace short to prevent reference ringing.
Do not exceed the VDD maximum of +5.5V; the part is not 3.3V-tolerant on its parallel digital outputs. When migrating from the obsolete -T variant to the RoHS +T variant, verify that the new part's pin 1 dot and notch orientation match the original PCB footprint - the WSOIC-24 mechanical outline is identical, but lot date codes and country-of-origin markings will differ. When using bipolar mode, ensure the BIP pin is tied to VDD before applying analog signals; otherwise the part will be in unipolar mode and negative inputs will clip at 0V.
Compliance-Informationen
MAX191BCWG-T is the legacy non-RoHS tube-packaging variant of the MAX191 12-bit SAR ADC. The +T suffix variants are RoHS-compliant with Pb-free terminal finish. Reach compliance and conflict-minerals compliance per Maxim Integrated product documentation; halogen-free status not explicitly stated in the verified web data.
