MAX194BCPE - 14-Bit 85ksps SAR ADC | Maxim Integrated / Analog Devices
N.º de pieza: MAX194BCPE ✗ Fin de vida| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $17.5 | $17,50 |
| 10 | $15.4 | $154,00 |
| 100 | $13.1 | $1.310,00 |
| 500 | $11.25 | $5.625,00 |
| 1.000 | $9.95 | $9.950,00 |
MAX194BCPE Descripción general
An SAR (Successive Approximation Register) ADC is a class of analog-to-digital converter that uses a comparator, an internal DAC, and a successive-approximation register to convert an analog input into a digital output one bit at a time per clock cycle. SAR ADCs sit in the data-converter IC hierarchy under ADC -> data converter -> signal chain IC -> mixed-signal semiconductor. They are favored over delta-sigma and pipeline ADCs in applications that require low latency, deterministic acquisition time, and small size with no input current integration artifact - making them ideal for multiplexing between channels and for closed-loop control systems.
Key features of the MAX194BCPE include 1/2 LSB integral nonlinearity, 9.4 microsecond conversion time, 10 microampere shutdown mode for battery-powered applications, built-in track-and-hold, AC and DC specifications, unipolar (0V to VREF) and bipolar (-VREF to VREF) input range, three-state serial-data output (SPI/QSPI/MICROWIRE compatible), and small 16-pin DIP, SO, and ceramic SB package options. Reference voltage and signal voltage each have dedicated input pins.
The MAX194BCPE uses a capacitive-DAC SAR core with auto-calibration of linear and offset errors at power-up. The serial interface allows easy integration into embedded systems; the CS input controls three-state serial output, and EOC can be tied to CONV for continuous full-speed conversions at up to 5 Mbps of SCLK. Pin-for-pin and functional compatibility with the MAX195 16-bit ADC simplifies migration paths when higher resolution is later needed.
Typical applications include data-acquisition boards, industrial process-control front-ends, battery-powered instrumentation, portable medical monitors, weigh scales, motor control current loops, and digital instrumentation replacement of legacy 14-bit converters. The 10 microampere shutdown mode is a major advantage in any battery-life-constrained system.
When designing with this ADC, ensure that the VREF input is properly bypassed and that the analog input is driven from a low-impedance source for full AC performance at 85 ksps. The two power-supply pins (VDD and VLOGIC) should be decoupled separately to prevent digital-coupling noise from degrading the analog-input SINAD.
This page synthesizes distributor pricing tiers, drop-in compatible 14-bit ADC alternatives, and practical PCB design notes not found in the bare datasheet.
Alternativas directas para MAX194BCPE — 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 MAX194BCPE (mismo factor de forma y huella) — difiere en Resolution, RoHS Status, Architecture, Operating Temperature Range, Shutdown Current.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
MAX194BCPE+
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MAX194BEPE
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MAX194CEPE
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MAX195CEPE
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MAX194BCPE Valores máximos y características eléctricas
| Resolución | 14 bit |
| Number of Channels | 1 |
| Frecuencia de muestreo | 85 ksps |
| Architecture | SAR (Successive Approximation) with capacitive DAC |
| Conversion Time | 9.4 us |
| Integral Nonlinearity (INL) | 1/2 LSB (max) |
| Signal-to-Noise and Distortion (SINAD) | 82 dB at 5 kHz input |
| Corriente de apagado | 10 uA |
| Analog Input Range | Unipolar 0V to VREF; Bipolar -VREF to +VREF |
| Interfaz | Serial (SPI / QSPI / MICROWIRE compatible) |
| Reference Voltage Input | External (dedicated VREF pin) |
| Supply Voltage (VDD) | 5 V (analog) + 3 V to 5.25 V (VLOGIC) |
| Encapsulado / Carcasa | 16-pin PDIP (PE) - through-hole |
| Rango de temperatura de funcionamiento | 0C to +70C (commercial, C grade) |
| Tipo de montaje | Through-Hole DIP |
| Track/Hold | Built-in |
| Auto-Calibration | Yes, internal (linearity + offset) |
| Estado RoHS | Non-compliant (PE suffix = PDIP with SnPb lead finish) |
Configuración de pines de MAX194BCPE
| Pin 1 | AIN — Analog input (true differential architecture) |
| Pin 2 | VREF — External reference voltage input |
| Pin 3 | AGND — Analog ground |
| Pin 4 | VDD — Positive analog supply, +5V |
| Pin 5 | AGND — Analog ground (additional) |
| Pin 6 | VLOGIC — Digital interface supply (3V to 5.25V) |
| Pin 7 | BIPOLAR — Input range select: high = bipolar, low = unipolar |
| Pin 8 | CONV — Convert start input; tie low for internal mode |
| Pin 9 | EOC — End-of-conversion output flag |
| Pin 10 | DGND — Digital ground |
| Pin 11 | DOUT — Serial data output (three-state) |
| Pin 12 | SCLK — Serial clock input |
| Pin 13 | NC — Not connected (per datasheet) |
| Pin 14 | NC — Not connected (per datasheet) |
| Pin 15 | NC — Not connected (per datasheet) |
| Pin 16 | CS — Chip select (active low, enables serial interface) |
Aplicaciones típicas
MAX194BCPE es adecuado para 6 aplicacións: Data Acquisition Systems, Motor Control Current Sensing, Battery-Powered Instrumentation, Industrial Process Control, Weigh Scales and Load-Cell Digitization, Replacement of Legacy 14-Bit Converters.
Data Acquisition Systems
The MAX194BCPE is widely used as the front-end ADC of multi-channel data-acquisition boards connected to industrial sensors. Its 14-bit resolution with 1/2 LSB INL and 82 dB SINAD is sufficient to digitize strain-gauge, RTD, thermocouple, and process-voltage signals at up to 85 ksps aggregate throughput. The 9.4 us conversion time and SPI-compatible serial output allow a single MAX194BCPE per channel, with multiple devices sharing an SPI bus under individual CS selects. With 10 uA shutdown current, it supports battery-powered remote-DAU designs where idle current budgets are tight.
Recomendado
Motor Control Current Sensing
In brushless DC and permanent-magnet motor drives, the MAX194BCPE provides deterministic 9.4 us acquisition latency inside a 20 kHz PWM current-control loop. Each phase-current shunt (typically 5-50 mohm) is amplified to a full-scale voltage fed into AIN, with the ADC converting each cycle to 14-bit signed feedback. The bipolar -VREF to +VREF input range conveniently digitizes bidirectional current, while the 10 uA shutdown supports intermittent current profiling in battery-powered tools.
Recomendado
Battery-Powered Instrumentation
Portable field instruments benefit from the MAX194BCPE's headline 10 uA shutdown mode, which lets the ADC idle between bursts of measurements and minimizes battery drain on Li-ion coin cells. The 14-bit resolution yields a usable dynamic range of ~82 dB, sufficient for handheld environmental sensors, pocket oscilloscopes, and portable medical monitors. Designers typically wake the device via the CS pin, take N conversions, then return to shutdown, multiplying battery life by orders of magnitude.
Recomendado
Industrial Process Control
The 0C to +70C commercial operating range of the MAX194BCPE suits indoor industrial control cabinets and PLC analog-input modules. Its 1/2 LSB INL guarantees predictable calibration against a fixed reference, simplifying the IEC 61131 analog-input firmware pipeline. Built-in auto-calibration of linearity and offset at every power-up eliminates the periodic recalibration cycles that traditionally plagued industrial sensor channels, supporting long-deployment sensor nodes that must hold factory calibration.
Recomendado
Weigh Scales and Load-Cell Digitization
Load-cell bridge amplifiers produce a low-frequency differential output (1 Hz to 100 Hz) that the MAX194BCPE digitizes at 85 ksps before software averaging. Each conversion at 14 bits yields 5 ppm resolution, and aggregating 64 samples via FIFO yields 16-bit-equivalent noise-free resolution sufficient for 0.01% weigh-scale accuracy. The bipolar input range accepts the +/-VREF signal directly from a load-cell amplifier output with no extra sign-handling circuitry.
Recomendado
Replacement of Legacy 14-Bit Converters
The MAX194BCPE serves as a drop-in upgrade to obsolete 14-bit SAR ADCs such as the AD574A, ADC574A, and AD7572. It improves on these older parts by adding built-in auto-calibration, a serial SPI-compatible interface (vs legacy parallel-bus), 10 uA shutdown, and 85 ksps throughput. Existing PCBs need only minor footprint confirmation because the 16-pin PDIP form factor, the AIN/VREF/CS/A0 interface pins, and the +5 V analog supply remain industry standard.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para MAX194BCPE — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | MAX194BCPE+ | MAX194BEPE | MAX194CEPE | MAX195CEPE |
|---|---|---|---|---|---|
| Package | PDIP-16 (PE) | PDIP-16 (PE) - same | PDIP-16 (PE) - same | PDIP-16 (PE) - same | PDIP-16 (PE) - same |
| Brand | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated |
| Resolution | 14 bit | 14 bit | 14 bit | 14 bit | 16 bit |
| Sampling Rate | 85 ksps | 85 ksps | 85 ksps | 85 ksps | 85 ksps |
| INL (max) | 1/2 LSB | 1/2 LSB | 1 LSB | 2 LSB | 1.5 LSB at 16-bit |
| Shutdown Current | 10 uA | 10 uA | 10 uA | 10 uA | 30 uA |
| Conversion Time | 9.4 us | 9.4 us | 9.4 us | 9.4 us | 9.4 us |
| RoHS Compliance | Non-compliant (SnPb) | Compliant (RoHS) | Non-compliant (SnPb) | Non-compliant (SnPb) | Non-compliant (SnPb) |
Diferenciadores clave
- Headline 10 microampere shutdown current for battery applications (frente a MAX195CEPE)
- Pin-for-pin compatible with the 16-bit MAX195 upgrade path (frente a ADS8344 (TI cross-brand))
- Built-in auto-calibration eliminates external linearity trims (frente a MAX194BEPE (B grade))
Notas de diseño
Decouple VDD (analog +5V) and VLOGIC (3V to 5.25V) independently with a 10 uF bulk + 0.1 uF ceramic each, placed within 5 mm of the IC pins. Sharing a single decoupling network between analog and digital supply pins causes digital-edge current spikes to couple into AIN and degrade SINAD below the 82 dB datasheet figure. Estimated: a 10 mA digital load transient at 10 ns rise produces a kick of ~100 mV on a shared rail decoupling network, which can exceed the 1/2 LSB input noise.
Route the AIN analog trace as a guarded differential pair with the AGND pin as a return, keeping the trace shorter than 50 mm to minimize stray pickup. Place the VREF decoupling capacitor (typically 1 uF tantalum in parallel with 0.1 uF ceramic) directly across VREF and AGND to prevent reference noise - the 14-bit conversion reference is VREF/16384, so a 5 V reference yields 305 uV per LSB. Any reference ripple above ~300 uV leaks straight into the conversion result.
Do not exceed the maximum +5V absolute-maximum on VDD or -0.3V on any analog input relative to AGND. Always issue a CONV pulse or hold CONV low for at least 10 us before reading SCLK, otherwise internal auto-calibration may not complete and INL degrades. For the bipolar mode, ensure the BIPOLAR pin is tied high before the first conversion; transition noise on this pin during a conversion produces an offset error of up to 1 LSB.
Información de cumplimiento
PE suffix indicates SnPb (lead-bearing) PDIP lead finish per Maxim Integrated ordering information. RoHS compliance requires the + suffix (MAX194BCPE+). REACH is compliant per the manufacturer statement; halogen-free status was not stated explicitly in the verified sources.
