MAX1081BCUP - 10-Bit 300/400ksps 8-CH Serial ADC | Maxim Integrated
N.º de pieza: MAX1081BCUP ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $12.55 | $12,55 |
| 10 | $11.3 | $113,00 |
| 100 | $10.1 | $1.010,00 |
| 500 | $9.05 | $4.525,00 |
| 1.000 | $8.4 | $8.400,00 |
MAX1081BCUP Descripción general
An SAR ADC is a successive-approximation register analog-to-digital converter - a category of data converter that uses a binary-search algorithm and an internal DAC to digitize an analog input one bit at a time per clock cycle. SAR ADCs occupy a middle position in the data-converter hierarchy between flash ADCs (fastest, lowest resolution) and sigma-delta ADCs (highest resolution, slowest). They deliver an excellent trade-off between speed, resolution, and power, which is why they dominate multi-channel, low-power embedded acquisition tasks.
Key features include software-configurable analog inputs (unipolar/bipolar, single-ended/differential), four software-selectable power modes (normal, REDP, FASTPD, FULLPD), a hardware active-low SHDN pin, and automatic shutdown at the end of conversion to minimize battery drain. Internal +2.5V reference eliminates the need for an external reference in many designs, while analog inputs accept 0V-to-VREF or +/- VREF rails.
The device combines a high-bandwidth track/hold (T/H) front-end that supports signals well beyond the Nyquist limit of its 400 ksps maximum sampling rate, ensuring accurate acquisition of fast transients. Its serial interface is SPI/QSPI/MICROWIRE-compatible, allowing direct connection to most microcontrollers and DSPs without glue logic.
Typical applications include portable data acquisition, battery-powered instrumentation, multichannel sensor monitoring, process control, patient monitoring, and pen digitizers. The 8-channel input mux makes it well-suited for systems that must digitize multiple analog sources with one ADC.
When designing with this part, place a 0.1uF bypass cap within 5 mm of VDD/REF pins and route analog and digital grounds separately back to a star ground to preserve the 10-bit linearity. AutoShutdown between conversions drops supply current to sub-microamp levels, so firmware should explicitly wake the part before each conversion burst.
This page consolidates distributor stock, datasheet links, drop-in TSSOP-20 alternatives, and practical layout guidance not found on a single manufacturer page.
Alternativas directas para MAX1081BCUP — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
Variantes de esta serie
Modelos de la misma serie compatibles directamente con MAX1081BCUP (mismo factor de forma y huella) — difiere en Resolution, Package, Sampling Rate, Internal Reference Voltage, RoHS Status.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
MAX1081BCUP+T
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MAX1081BEUP+
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MAX1081BEUP+T
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MAX1081AEUP+
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MAX1080BCUP+
✅ Sustitución directa✓ En stock
$5.02 / unidad
Ver hoja de datos →MAX1081BCUP Valores máximos y características eléctricas
| Resolución | 10 bit |
| Number of Input Channels | 8 (single-ended) / 4 (differential, software-configurable) |
| Frecuencia de muestreo | 400 ksps (external clock, MAX1081) / 300 ksps (internal clock) |
| Tensión de alimentación | +2.7 V to +3.6 V (single supply, MAX1081) |
| Supply Current (Normal Operation) | 2.5 mA typical |
| Supply Current (Full Power-Down) | <= 10 uA (FULLPD mode) |
| Internal Reference Voltage | +2.5 V |
| Analog Input Range | 0 V to VREF (unipolar) or +/- VREF (bipolar) |
| Architecture | SAR (Successive Approximation Register) |
| Interfaz | SPI / QSPI / MICROWIRE-compatible serial |
| Shutdown Pin | Active-low SHDN |
| Power Modes | Normal, REDP, FASTPD, FULLPD (AutoShutdown at end of conversion) |
| Encapsulado | 20-pin TSSOP |
| Rango de temperatura de funcionamiento | 0C to +70C (commercial, 'C' suffix) |
| Tipo de montaje | Surface Mount |
| Estado RoHS | Compliant (MAX1081BCUP+) |
Configuración de pines de MAX1081BCUP
| 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 | AIN6 — Analog input channel 6 |
| Pin 8 | AIN7 — Analog input channel 7 |
| Pin 9 | AGND — Analog ground |
| Pin 10 | REFADJ — Reference adjust (for external reference trim) |
| Pin 11 | REF — Internal +2.5V reference output |
| Pin 12 | VDD — Positive supply voltage (+2.7V to +3.6V) |
| Pin 13 | GND — Digital ground |
| Pin 14 | SCLK — Serial clock input |
| Pin 15 | CS — Active-low chip select |
| Pin 16 | DIN — Serial data input |
| Pin 17 | DOUT — Serial data output |
| Pin 18 | SHDN — Active-low shutdown input |
| Pin 19 | NC — Not connected (per datasheet) |
| Pin 20 | NC — Not connected (per datasheet) |
Aplicaciones típicas
MAX1081BCUP es adecuado para 6 aplicacións: Portable Battery-Powered Data Acquisition, Multichannel Industrial Sensor Monitoring, Patient Monitoring and Medical Instrumentation, Pen Digitizers and Touch-Screen Controllers, Process Control and PLC Analog Input Modules, Automotive Telematics and Battery Management.
Portable Battery-Powered Data Acquisition
The MAX1081BCUP's +2.7V to +3.6V single-supply operation and 2.5 mA typical current with AutoShutdown dropping to under 10 uA between conversions make it ideal for battery-powered data acquisition in handheld instruments. With 8 software-configurable analog inputs and a 400 ksps max sampling rate, a single ADC can digitize temperature, pressure, voltage, and current sensors simultaneously, reducing BOM count. The internal +2.5V reference eliminates the external reference IC, PCB area, and leakage path typical of portable enclosures. Designers route analog and digital grounds to a single star point and place a 0.1 uF bypass within 5 mm of VDD, keeping total quiescent draw near the 2.5 mA datasheet figure for multi-day battery life.
Recomendado
Multichannel Industrial Sensor Monitoring
In industrial sensor monitoring panels, the MAX1081BCUP's 8 input channels allow one ADC to replace eight discrete ADCs or an expensive multi-channel sigma-delta part. The SAR architecture delivers deterministic 400 ksps throughput with no pipeline delay, so control loops see conversion latency as a fixed budget rather than a variable. Pseudo-differential input configuration rejects common-mode noise on long sensor cables. The MAX1081's AutoShutdown modes (NORMAL, REDP, FASTPD, FULLPD) let firmware trade speed versus power at run time, which is valuable when a panel wakes from sleep only to read four sensors every 100 ms. A separate ground return for analog and digital supplies keeps 10-bit linearity intact in noisy industrial cabinets.
Recomendado
Patient Monitoring and Medical Instrumentation
The MAX1081BCUP's low power and small 20-pin TSSOP footprint suit compact patient monitoring devices such as ambulatory ECG, blood-pressure cuffs, and pulse-oximetry front-ends. Eight analog inputs handle multiple bioelectric channels plus temperature and battery voltage, while the internal +2.5V reference keeps calibration stable across the 0C to +70C commercial temperature span. SPI/QSPI/MICROWIRE compatibility lets the ADC communicate with low-power microcontrollers (e.g., ARM Cortex-M0+) without level shifters, simplifying isolation barrier design. The MAX1081AEUP+ variant with automotive/medical-grade screening extends coverage to harsher thermal environments. Conductive EMI is minimized by the AutoShutdown between conversions and short serial bursts.
Recomendado
Pen Digitizers and Touch-Screen Controllers
The MAX1081BCUP's 400 ksps max sampling rate and 8-channel input mux support pen digitizer tablets that scan multiple horizontal and vertical electrode lines at low latency. SAR architecture gives instant conversion completion, critical for tracking fast pen strokes without perceptible lag. Unipolar input configuration drives each digitizer line sequentially through the analog mux, while AutoShutdown between scans keeps idle current under 10 uA, extending tablet battery life between charges. The 20-pin TSSOP package is small enough to fit behind the active area, and SPI interface runs directly to the host microcontroller for coordinate reporting. Digital ground isolation prevents kHz from being aliased into pen position readings.
Recomendado
Process Control and PLC Analog Input Modules
PLC analog input modules can use the MAX1081BCUP to digitize 8 process variables per chip - 4-20 mA loops, RTD voltages, thermocouple amplified outputs - with deterministic latency that simplifies IEC 61131 control-loop timing. Bipolar input configuration (-VREF to +VREF) handles both positive and negative sensor signals without external signal conditioning, while the 2.5V internal reference is sufficient for 10-bit absolute accuracy when properly buffered. Four software-selectable power modes let the PLC scan channels at different rates (e.g., 100 Hz for temperature, 1 kHz for vibration) using the same ADC. Stack multiple MAX1081BCUPs in parallel on a shared SPI bus with separate chip-select lines to expand to 32 or more channels.
Recomendado
Automotive Telematics and Battery Management
In automotive telematics modules, the MAX1081BCUP can be paired with the pin-compatible MAX1081AEUP+ (automotive temperature grade) to monitor up to 8 vehicle analog signals - battery voltage, cabin temperature, fuel level, accelerometer outputs - on a single +3.3V rail. SAR architecture gives predictable conversion latency for time-stamping sensor events sent over CAN or LTE-M. AutoShutdown between CAN message bursts keeps idle consumption negligible, important for always-on telematics boxes that drain the 12V battery when the car is parked. The 20-pin TSSOP footprint is small enough for placement near antenna or sensor connectors. Analog and digital grounds must meet at one star point to preserve 10-bit linearity under automotive EMI.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para MAX1081BCUP — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | MAX1081BCUP+T | MAX1081BEUP+ | MAX1081BEUP+T | MAX1081AEUP+ | MAX1080BCUP+ |
|---|---|---|---|---|---|---|
| Package | 20-TSSOP | 20-TSSOP - same | 20-TSSOP - same | 20-TSSOP - same | 20-TSSOP - same | 20-TSSOP - same |
| Brand | Analog Devices (Maxim Integrated) | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Resolution | 10 bit | 10 bit | 10 bit | 10 bit | 10 bit | 10 bit |
| Supply Voltage | +2.7V to +3.6V | +2.7V to +3.6V | +2.7V to +3.6V | +2.7V to +3.6V | +2.7V to +3.6V | +4.5V to +5.5V |
| Sampling Rate (max) | 400 ksps | 400 ksps | 400 ksps | 400 ksps | 400 ksps | 400 ksps |
| Number of Input Channels | 8 | 8 | 8 | 8 | 8 | 8 |
| Operating Temperature Range | 0C to +70C | 0C to +70C | -40C to +85C | -40C to +85C | Automotive grade | 0C to +70C |
| Internal Reference | +2.5V (internal) | +2.5V | +2.5V | +2.5V | +2.5V | +4.096V |
Diferenciadores clave
- AutoShutdown reduces idle current to under 10 uA between conversions (frente a MAX1080BCUP+)
- 8 software-configurable analog inputs in a 20-pin TSSOP (frente a MAX1280BCUP)
- Internal +2.5V reference eliminates external reference IC (frente a Pin-compatible discrete-ADC designs with external reference)
Notas de diseño
Place a 0.1 uF ceramic bypass capacitor within 5 mm of the VDD pin (pin 12) and another 0.1 uF close to the REF pin (pin 11). The internal +2.5V reference is sensitive to digital switching noise, so the REF pin should be bypassed even when the internal reference is the only one used. For best full-scale accuracy, add a 10 uF tantalum in parallel with the 0.1 uF on VDD to absorb the SAR current transients during bit-trial switching.
Route analog (AIN0-AIN7, REF, AGND) and digital (SCLK, CS, DIN, DOUT, SHDN, GND) signals on opposite sides of the package, with separate analog and digital ground planes joined at a single star point under the IC. This star-ground pattern is critical for the 10-bit linearity at 400 ksps; even small ground-loop voltages (a few mV) can degrade INL. Keep digital traces away from AIN pins to prevent capacitive coupling that would corrupt the sample-and-hold acquisition.
Do not apply voltages above VDD + 0.3 V to any analog input - the absolute maximum on AIN pins is VDD + 0.3 V. If your sensor signal can exceed VDD (for example, a 5V rail feeding into a 3.3V ADC), add a 10 kohm series resistor and external clamp diodes, or choose the pin-compatible MAX1080BCUP+ for native 5V operation. Also ensure SHDN (pin 18) is tied high through a 100 kohm pull-up if not actively driven - leaving SHDN floating can leave the part in an undefined shutdown state at power-up.
When stacking multiple MAX1081BCUPs on a shared SPI bus, give each its own CS line and a 100 kohm pull-up on CS to keep the ADC deselected during power-up. Bus capacitance from long SPI traces can slow down DOUT edges; if the SPI clock exceeds 10 MHz, add a 33 pF series resistor near each DOUT pin to dampen reflections. For systems where the SPI bus runs longer than 50 mm, prefer a lower clock rate (1-2 MHz) to maintain 10-bit acquisition accuracy.
Información de cumplimiento
MAX1081BCUP+ is RoHS-compliant per the '+' suffix. MAX1081BCUP (without '+') is the legacy non-RoHS variant; the '+' version is the recommended choice for new designs. AEC-Q100 only applies to MAX1081AEUP+.
