MAX1243BEPA - 10-Bit SAR ADC, 73ksps, SPI, DIP-8 | Maxim
N.º de pieza: MAX1243BEPA ✗ Fin de vida| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $3.32 | $3,32 |
| 10 | $2.99 | $29,90 |
| 100 | $2.65 | $265,00 |
| 500 | $2.31 | $1.155,00 |
| 1.000 | $2.05 | $2.050,00 |
MAX1243BEPA Descripción general
A successive-approximation register (SAR) ADC is a type of data converter that performs a binary search through an internal capacitive DAC to digitize an analog input one bit at a time, completing a full conversion in N clock cycles for N bits of resolution. SAR ADCs occupy a middle position in the converter taxonomy - more sample-rate capable than integrating ADCs (such as dual-slope types) but lower-power and lower-latency than pipelined or sigma-delta ADCs, making them the default choice for multiplexed data acquisition, sensor signal chains, and instrumentation sample rates from a few ksps to several hundred ksps.
Key features of the MAX1243BEPA include 10-bit resolution with no missing codes, an internal 4.096V reference option in some family members (external reference on the -B grade), single-ended analog input channel, 3-wire serial digital interface, low supply current, automatic power-down between conversions, and an SO-8/PDIP-8 pin footprint. The "B" speed grade and "E" temperature grade combination positions the part for industrial -40C to +85C environments. Compared with earlier generation ADCs, the on-chip track/hold eliminates the need for an external buffer amplifier at modest input bandwidths, simplifying BOM cost.
The MAX1243BEPA shares its SAR architecture, pinout, and serial protocol with the broader MAX1240/MAX1242/MAX1243 family. Designers can move between 10-bit and 12-bit resolutions (MAX1240 family) and between 73ksps (MAX1243) and slower 133ksps (MAX1241/MAX1245) grades without changing firmware, provided the timing registers are updated.
Typical applications include portable instrumentation, sensor signal conditioning, battery monitoring, pen digitizers, and process control data acquisition. The wide 2.7V-5.25V supply range and very low operating current also suit it for loop-powered 4-20mA transmitters and remote, solar-powered telemetry nodes. When designing with the MAX1243BEPA, observe the reference decoupling guidance: place the 0.1uF reference bypass capacitor as close as possible to REF (pin 1) to minimize conversion errors caused by reference noise and digital switching transients coupling into the analog input.
This page synthesizes distributor pricing, drop-in same-package and cross-brand alternatives, and practical design notes not found in the manufacturer datasheet.
Alternativas directas para MAX1243BEPA — 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 MAX1243BEPA (mismo factor de forma y huella) — difiere en Package, Sampling Rate, Input Type, Reference Type, Mounting Type.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
MAX1243AEPA+
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MAX1243BCPA+
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MAX1242BEPA
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MAX1240BEPA+
✅ Sustitución directa✓ En stock
$5.55 / unidad
Ver hoja de datos →MAX1243ACPA
✅ Sustitución directa✓ En stock
$5.92 / unidad
Ver hoja de datos →MAX1243BEPA Valores máximos y características eléctricas
| Resolución | 10 bits |
| Number of Channels | 1 (single-ended) |
| Frecuencia de muestreo | 73 ksps |
| Conversion Architecture | SAR (Successive Approximation) |
| Conversion Time | 7.5 us (typ) |
| Track/Hold Acquisition Time | 1.5 us (typ) |
| Supply Voltage (VDD) | +2.7 V to +5.25 V |
| Reference Type | External (B-grade) |
| Digital Interface | SPI / QSPI / MICROWIRE 3-wire |
| Input Type | Single-ended analog input |
| Rango de temperatura de funcionamiento | -40 to +85 C (E-grade) |
| Encapsulado | PDIP-8 (E package, through-hole) |
| Tipo de montaje | Through-Hole |
| Estado RoHS | Compliant (EPA/+ versions) |
| Número de pines | 8 |
| Nivel MSL | 1 (unlimited, through-hole) |
Configuración de pines de MAX1243BEPA
| Pin 1 | VDD — +2.7V to +5.25V supply voltage |
| Pin 2 | AIN — Analog input (single-ended) |
| Pin 3 | GND — Ground |
| Pin 4 | DOUT — Serial data output (SPI) |
| Pin 5 | SSTRB — Serial strobe (optional status) |
| Pin 6 | SCLK — Serial clock input |
| Pin 7 | CS — Chip select (active low) |
| Pin 8 | REF — External reference voltage input |
Aplicaciones típicas
MAX1243BEPA es adecuado para 6 aplicacións: Portable Battery-Powered Instrumentation, Sensor Signal Conditioning and Data Acquisition, Process Control Loop Monitoring, Pen Digitizer and Touch Input Systems, Remote Telemetry and Solar-Powered Nodes, Industrial Control Panel Front-Ends.
Portable Battery-Powered Instrumentation
The MAX1243BEPA's +2.7V to +5.25V single-supply range and automatic power-down between conversions suit it for handheld digital instruments where battery life is critical. Typical battery drain is below 1mA during continuous conversion and drops sharply between samples when CS (pin 7) is held high. The 10-bit resolution is sufficient for 0.5% of full-scale precision in thermistor-, strain-gauge-, or current-sense-based measurements. In a handheld digital multimeter, the MAX1243BEPA digitizes a scaled shunt voltage or thermocouple output directly, with an external precision reference (such as the MAX6190A) determining absolute accuracy. Compared with integrating ADCs, the SAR approach settles in microseconds - critical for full-scope waveform capture on autoranging events.
Recomendado
Sensor Signal Conditioning and Data Acquisition
The MAX1243BEPA serves as a single-channel 10-bit digitizer for analog sensor outputs in industrial data acquisition systems. Its 7.5us SAR conversion time and 1.5us track/hold acquisition handle 73 ksps sample rates, comfortably supporting temperature, pressure, and flow transmitters sampled at a few hundred Hz. Place the MAX1243BEPA behind a front-end op-amp (such as the MAX4475) that scales and low-pass filters the sensor signal; the ADC's external reference lets you scale the full-scale input range to match the conditioned sensor voltage. In 4-20mA loop-powered transmitters, the wide 2.7V-5.25V supply tolerates the loop compliance voltage drop while keeping ADC power dissipation low.
Recomendado
Process Control Loop Monitoring
Industrial process control demands reliable digitizing of slow analog sensor signals - temperature, pressure, level - where 10-bit resolution is adequate and the cost of a precision 16-bit converter is not. The MAX1243BEPA's -40C to +85C industrial E-grade ensures operation across factory floor ambient ranges, while the 3-wire SPI interface connects to any microcontroller or PLC. Combined with an external multiplexer (such as the MAX4617) the MAX1243BEPA can scan 8 or more analog inputs sequentially, supporting small-scale SCADA I/O modules. The external reference lets you scale the full-scale ADC range to the loop signal (e.g., 1-5V), preserving accuracy at the bottom of the 4-20mA span.
Recomendado
Pen Digitizer and Touch Input Systems
The MAX1243BEPA's high 73 ksps sampling rate and SPI-compatible digital interface make it a natural fit for digitizing pen or stylus position signals in tablet, signature capture, and pen digitizer systems. The fast track/hold acquisition captures the rapidly changing stylus waveform without missing transient peaks. The 10-bit resolution is adequate for coordinate plotting where each axis needs roughly 0.1% positional accuracy. The wide supply tolerance allows the ADC to share the 3.3V digital rail with the host microcontroller, eliminating a separate analog regulator. The PDIP-8 package is breadboard-friendly for prototype pen-digitizer boards.
Recomendado
Remote Telemetry and Solar-Powered Nodes
The MAX1243BEPA's very low operating current and wide supply tolerance support remote, solar-powered telemetry nodes where every microwatt counts. The automatic power-down between conversions reduces average supply current to the microampere range when sampled at slow rates (e.g., once per minute for environmental monitoring), making it ideal for battery- or solar-backed wireless sensor nodes. The 2.7V minimum supply lets it operate down to near-end-of-discharge for 3.6V LiSOCl2 primary cells, maximizing battery life. The 10-bit resolution is sufficient for soil moisture, temperature, and slow-changing environmental telemetry.
Recomendado
Industrial Control Panel Front-Ends
Human-machine interface (HMI) panels and industrial control front-ends often require one or two channels of low-speed analog digitization for knob, slider, or analog sensor input. The MAX1243BEPA fits naturally behind a rotary encoder's analog tap, a potentiometer, or a low-frequency analog signal conditioner. Its 3-wire SPI/QSPI/MICROWIRE interface is supported by virtually any microcontroller, including the MAXQ2000 and MAX32625 families, allowing tight integration without complex glue logic. The -40C to +85C E-grade ensures operation across factory shop floors and outdoor installations, while the PDIP-8 form factor simplifies through-hole PCB assembly.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para MAX1243BEPA — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | MAX1243AEPA+ | MAX1243BCPA+ | MAX1242BEPA | MAX1240BEPA+ |
|---|---|---|---|---|---|
| Brand | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated |
| Package | PDIP-8 | PDIP-8 - same | PDIP-8 - same | PDIP-8 - same | PDIP-8 - same |
| Resolution | 10 bits | 10 bits | 10 bits | 10 bits | 12 bits |
| Sampling Rate | 73 ksps | 73 ksps | 73 ksps | 73 ksps | 73 ksps |
| Reference Type | External | Internal 4.096V | External | Internal | External |
| Temperature Grade | Industrial -40C to +85C | Industrial -40C to +85C | Industrial -40C to +85C | Industrial -40C to +85C | Industrial -40C to +85C |
| Supply Voltage Range | +2.7V to +5.25V | +2.7V to +5.25V | +2.7V to +5.25V | +2.7V to +5.25V | +2.7V to +5.25V |
| Serial Interface | 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 |
Diferenciadores clave
- External reference option allows scalable full-scale input range (frente a MAX1243AEPA+)
- Through-hole PDIP-8 package simplifies prototyping and breadboarding (frente a MAX1243BCPA+)
- Wider temperature grade suitable for industrial environments (frente a MAX1243ACPA)
Notas de diseño
The MAX1243BEPA supports automatic power-down between conversions when CS (pin 7) is held high. To minimize average supply current in battery-powered or solar-powered applications, sample at the lowest rate that meets bandwidth requirements and keep the device powered down otherwise. A 0.1uF ceramic decoupling capacitor placed as close as possible to VDD (pin 1) and GND (pin 3) suppresses digital switching noise coupling into the analog input.
The external reference voltage at REF (pin 8) must be properly bypassed. Place a 0.1uF ceramic capacitor as close as possible to REF with a short ground return. Reference noise appears directly as conversion error - inadequate bypassing is the most common cause of degraded SNR. The reference voltage should be between 1.0V and VDD; do not exceed VDD at the REF pin.
Keep the analog input trace (pin 2 AIN) as short as possible and away from digital lines (SCLK, DOUT, CS) to minimize digital-to-analog crosstalk. Use a ground plane beneath the ADC and avoid routing high-speed digital traces under the analog input pin. Place input and reference bypass capacitors on the same side of the PCB as the ADC, with short traces to the IC pins. For surface-mount variants (MAX1243BCSA in SO-8), follow the same layout guidance.
Información de cumplimiento
RoHS compliance applies to MAX1243BEPA+ (with + suffix); the legacy MAX1243BEPA without + is non-RoHS. AEC-Q100 not applicable - choose automotive-grade equivalents for AEC-Q100 designs.
