ADS774JP - 12-Bit 125 kSPS SAR ADC | Texas Instruments
N.º de pieza: ADS774JP ✗ Fin de vidaADS774JP Descripción general
An SAR ADC is a sampling data-conversion device that compares the sampled input voltage against an internal capacitor DAC during each conversion. The ADS774JP uses a capacitor array implemented in low-power CMOS technology to perform successive comparisons. Its integrated sampling and microprocessor interface simplify analog acquisition while reducing the external component count compared with older converter families such as ADC574, ADC674, and ADC774.
The principal operating characteristics include 12-bit resolution, one analog input channel, 8.5 microseconds maximum conversion time, and operation from a single +5 V supply. According to the manufacturer datasheet, the ADS774 family can replace ADC574, ADC674, and ADC774 models in most applications while providing internal sampling and lower power consumption. These characteristics make it suitable for industrial data acquisition, process control, instrumentation, and microprocessor-based measurement systems.
The internal sampling architecture eliminates a separate sample-and-hold circuit in most applications. The parallel interface provides direct connection to microprocessor or microcontroller input ports, allowing converted codes to be read through digital bus lines. The converter is intended for designs requiring repeatable single-ended or bipolar acquisition rather than the throughput of very high-speed pipeline ADCs.
Designers should use the manufacturer pin-description table and application information when assigning PCB signals and selecting interface logic. Particular attention is required to input range, reference behavior, acquisition timing, digital bus timing, and power-supply bypassing. The ADS774JP is listed as obsolete by a product listing, so engineers should verify lifecycle status and replacement availability before starting a new production design.
This page combines the principal ADS774JP operating characteristics, verified package information, lifecycle context, and practical application guidance with a restrained drop-in comparison approach. It emphasizes engineering suitability rather than treating related converter models as interchangeable without checking their exact pinout, input architecture, interface timing, and acquisition requirements.
Alternativas directas para ADS774JP — 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 ADS774JP (mismo factor de forma y huella) — difiere en Architecture, Supply Voltage, Mounting Type, Package, Clock.
ADS774JEG4
✅ Sustitución directaConsulte el precio
Ver hoja de datos →ADS774JU
✅ Sustitución directaConsulte el precio
Ver hoja de datos →MAX174ACPI+
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
ADS774JP Valores máximos y características eléctricas
| Resolución | 12 bit |
| Converter Type | Successive approximation ADC (SAR) |
| Number of Analog Input Channels | 1 channel |
| Maximum Sampling Rate | 125 kSPS |
| Maximum Conversion Time | 8.5 us |
| Rango de tensión de entrada | Unipolar or bipolar input |
| Reference | Internal reference |
| Digital Interface | Parallel microprocessor-compatible interface |
| Tensión de alimentación | +5 V single supply |
| Internal Architecture | Capacitor DAC (CDAC) implemented in low-power CMOS |
| Sampling Circuit | Internal sampling |
| Clock | Internal clock |
| Encapsulado | 28-pin PDIP |
| Tipo de montaje | Through-hole |
| Analog Input Type | Single-ended or differential |
Guía de configuración de pines de ADS774JP 28-pin pdip
Configuración de pines para ADS774JP (encapsulado 28-pin pdip). Este componente analógico presenta pines de entrada, salida y alimentación. Consulte la hoja de datos del fabricante para conocer las configuraciones de los pines de ajuste de offset, compensación y habilitación. Ideal para circuitos de acondicionamiento de señal y amplificadores.
No hay datos detallados de patillaje disponibles para ADS774JP.
Consulte la hoja de datos para ver la configuración completa de patillas.
Aplicaciones típicas
ADS774JP es adecuado para 6 aplicacións: Industrial Process Measurement, Microprocessor Data-Acquisition System, Laboratory Instrumentation, Embedded Control and Monitoring, Power-Supply Feedback Monitoring, Legacy Equipment Maintenance.
Industrial Process Measurement
The ADS774JP suits process-control channels that convert a slowly changing pressure, temperature, or level signal into a 12-bit digital value for a microprocessor. Its 125 kSPS maximum sampling rate is substantially faster than most process-control loops require, while internal sampling, reference, and clock functions simplify analog front-end design. A unipolar input can be used for sensor outputs referenced to ground, or the input stage can support bipolar instrumentation signals. Board designers should keep high-impedance sources short, provide stable reference and supply bypassing, and place the converter close enough to minimize pickup on the analog input. Verify the complete input range and common-mode requirements in the manufacturer datasheet before scaling the sensor signal.
Recomendado
Microprocessor Data-Acquisition System
The ADS774JP provides a practical parallel-interface ADC front end for a microprocessor or microcontroller-based acquisition system. At 12 bits and 125 kSPS, it suits instrumentation that gathers multiple slow analog channels through multiplexing rather than simultaneous high-speed sampling. Its internal sampling and clock reduce the need for a separate sample-and-hold device and external conversion clock, while the parallel bus allows converted data to be read through digital port lines. The acquisition controller should observe the conversion timing and bus-control signals shown in the datasheet. Grounding and decoupling remain important because the converter shares a board with digital logic and switching regulators.
Recomendado
Laboratory Instrumentation
The ADS774JP can serve as the conversion stage in laboratory measurement equipment that translates an analog input into a 12-bit code for display, logging, or closed-loop control. The internal reference and single +5 V supply help reduce the number of support components, while the 8.5 microsecond maximum conversion time supports responsive single-channel readings. For bench instruments, use a shielded analog front end, a clean low-noise reference path, and separated return-current routing to prevent digital switching activity from shifting the conversion result. If the instrument must resolve very small signals, verify the input noise and accuracy limits in the manufacturer datasheet rather than relying on nominal resolution alone.
Recomendado
Embedded Control and Monitoring
The ADS774JP is appropriate for embedded equipment that monitors one analog process variable and reports it through a host processor. Its single-channel architecture avoids the power and routing overhead of a wide multiplexed converter, and the microprocessor-compatible interface supports straightforward code acquisition. The 125 kSPS capability permits oversampling relative to a slow control loop, although the implementation should account for the ADC’s actual bandwidth, conversion interval, and acquisition requirements. A practical design can use the MCU for configuration, filtering, alarms, and actuator decisions while the ADS774JP performs the initial conversion. Firmware should perform input settling before each conversion and validate data against the digital interface timing diagram.
Recomendado
Power-Supply Feedback Monitoring
The ADS774JP can monitor an analog feedback or output rail in a power-supply control system when the voltage is conditioned into its supported input range. The 12-bit code provides enough resolution for supervisory thresholds and trend tracking in many non-precision applications, while the single +5 V supply matches commonly available control electronics. Sampling at 125 kSPS is fast enough to capture supply transients when the associated analog front end and signal path have suitable bandwidth. Designers should use isolated or appropriately rated measurement methods when the monitored rail exceeds the converter’s input limits. A differential input configuration and careful common-mode analysis can reduce errors in high-side measurements, but every protection component must preserve accuracy and transient response.
Recomendado
Legacy Equipment Maintenance
The ADS774JP is most practical in maintenance programs that reproduce the function of an existing ADS774-family board or a legacy converter design using a 28-PDIP footprint. The 12-bit, 125 kSPS SAR architecture and parallel interface support direct board-level substitution when the original schematic and pin mapping match. Before installation, compare the full ordering suffix, temperature grade, reference behavior, input configuration, and acquisition timing of the installed device. The part is listed as obsolete, so procurement should focus on traceable inventory and documented inspection rather than assuming long-term repeatability. For new production equipment, a supported converter with verified timing and pin compatibility is generally the lower-risk choice.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para ADS774JP — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | ADS774JE | ADS774JU | MAX174ACPI+ |
|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Maxim Integrated |
| Package | 28-pin PDIP | 28-pin PDIP | 28-pin PDIP | 28-pin PDIP |
Diferenciadores clave
- Faster maximum conversion time than the identified cross-brand substitute (frente a MAX174ACPI+)
- Same converter performance within the ADS774 family (frente a ADS774JE)
- Internal sampling, reference, and clock integration (frente a ADS774JU)
Notas de diseño
Route the analog input directly to the ADS774JP with a short trace and place the associated input-network components close to the converter. Keep digital output traces away from the analog input and reference paths to minimize capacitive coupling. Use a common ground plane with careful separation of analog and digital return currents, and follow the manufacturer application diagram for supply bypassing and input-reference layout.
Decouple the +5 V supply near the converter pins and keep the power trace sufficiently wide for the converter’s supply-current transients. Place the capacitor on the same board side as the device and connect it through a short ground path. Confirm the recommended capacitor value and stability configuration in the manufacturer datasheet, especially if the supply is shared with switching circuitry or a long harness.
Do not assume that every legacy ADC with a 28-pin package is electrically interchangeable. Before replacing ADS774JP, verify input range and polarity, reference connection, conversion timing, read-data control sequence, logic levels, acquisition settling, and temperature grade. The MAX174ACPI+ is described as compatible in most 28-DIP configurations, but its 10 microsecond conversion time differs from the 8.5 microsecond ADS774JP maximum and may affect sampling timing.
Treat the parallel data and control interface as a synchronous bus. Use the manufacturer timing diagram to determine when output data may be sampled and when the converter may begin another conversion. Account for propagation delay through the processor, address decoding, and any level-shifting components. If the bus is long or heavily loaded, buffer the signals and keep clock or control routing away from sensitive analog nodes.
Información de cumplimiento
The exact-suffix RoHS, REACH, lead-free, halogen-free, and conflict-minerals declarations were not established. AEC-Q100 is not applicable to this general-purpose data-conversion device based on its stated application class.