COP431CN/NOPB - 8-bit Serial I/O ADC, DIP-8 | Texas Instruments
N.º da peça: COP431CN/NOPB ✓ Ativo| Qtd. | Preço unitário | Total |
|---|---|---|
| 1 | $6.45 | $6,45 |
| 10 | $5.82 | $58,20 |
| 100 | $5.18 | $518,00 |
| 500 | $4.62 | $2.310,00 |
| 1.000 | $4.1 | $4.100,00 |
COP431CN/NOPB Visão geral
An 8-bit ADC is a data-acquisition converter that translates an analog input voltage into a digital code with 256 discrete quantization levels (28 = 256), giving a least-significant-bit (LSB) step of full-scale / 256. SAR (successive-approximation register) ADCs are the dominant topology for medium-speed, low-to-medium resolution applications because they deliver deterministic latency, zero pipeline delay, and excellent DC accuracy. The COP431CN/NOPB belongs to the data converter IC family, within the broader signal-chain and data-acquisition hierarchy (ADC -> data converter -> analog/mixed-signal IC -> semiconductor).
Key features of the COP431CN/NOPB include its serial I/O architecture, which minimizes PCB trace count and simplifies routing compared with parallel-output ADCs; commercial-grade temperature rating suitable for 0 C to +70 C operation; through-hole DIP-8 mechanical format that allows easy prototyping, breadboarding, and socketed replacement; and an internal clock generator that removes the need for an external ADC clock. The part is offered by Texas Instruments and was originally released by National Semiconductor, now part of TI's data-converter portfolio.
The COP431CN/NOPB is typically used in legacy industrial controllers, simple sensor-digitization front ends, instrumentation front panels, and education/development platforms where an 8-bit converter with low pin count is preferred. The serial interface pairs naturally with microcontrollers such as the COP8 and other 8051-class devices that lack a parallel external bus, reducing MCU pin consumption from 11 lines (8 data + 3 control) to typically 3 lines (CS, CLK, DOUT).
When designing with the COP431CN/NOPB, observe the reference-voltage decoupling recommendations and ensure the analog input does not exceed the reference or absolute-maximum ratings. Because the part is a through-hole DIP-8, expect to allocate modest PCB area; if board real-estate is critical, verify whether a newer TI 8-bit serial ADC with an SOIC-8 footprint is acceptable as a redesign.
This page synthesizes distributor pricing for the COP431CN/NOPB, available drop-in alternatives, and practical design notes that go beyond the manufacturer datasheet, including an honest assessment of when this legacy ADC remains the best choice versus when a modern SOIC-8 part is preferable.
Alternativas drop-in para COP431CN/NOPB — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
Ferramenta de comparação rápida — selecione peças alternativas para comparação lado a lado:
COP431CN
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
COP431CN/NOPB Classificações máximas e características elétricas
| Resolução | 8 bit |
| Number of Channels | 1 |
| Converter Type | SAR (Successive Approximation) |
| Interface | Serial (3-wire: CS, CLK, DOUT) |
| Input Type | Single-ended analog |
| On-chip Clock | Yes (internal clock generator) |
| Encapsulamento | 8-pin PDIP (DIP-8), through-hole |
| Terminal Form | Through-Hole |
| Number of Terminals | 8 |
| Package Code | DIP |
| Package Shape | RECTANGULAR |
| Temperature Grade | Commercial |
| Tensão de referência | External (required) |
| Tipo de montagem | Through-Hole |
| Status RoHS | Compliant (NOPB suffix indicates lead-free) |
| Manufacturer | Texas Instruments (formerly National Semiconductor) |
Configuração de pinos do COP431CN/NOPB
| Pino 1 | VREF — External reference voltage input |
| Pino 2 | VIN — Analog input |
| Pino 3 | GND — Ground |
| Pino 4 | DOUT — Serial data output (conversion result) |
| Pino 5 | CLK — Serial clock input |
| Pino 6 | CS — Chip select (active low) |
| Pino 7 | VDD — Positive supply voltage |
| Pino 8 | NC — Not connected (per datasheet) |
Aplicações típicas
COP431CN/NOPB é adequado para 6 aplicaçãos: Legacy Industrial Sensor Digitization, Microcontroller Analog Input Expansion, Portable Battery-Powered Measurement, Education and Development Platforms, Instrumentation Front Panel Readout, Automotive Aftermarket and Hobbyist Modules.
Legacy Industrial Sensor Digitization
The COP431CN/NOPB fits legacy industrial sensor front ends because it combines an 8-bit SAR ADC core with an integrated clock and a 3-wire serial interface in a single DIP-8 part. The 3-wire protocol (CS, CLK, DOUT) requires only three microcontroller GPIO pins, leaving the remaining I/O available for keypad, display, and actuator control on a typical industrial PLC daughter board. Operating from a single +5 V supply with an external reference (typically 2.5 V or 5.0 V), the part digitizes analog signals from thermocouples, strain gauges, and process-control transducers with 256-step resolution (1 LSB = VREF / 256, e.g. 19.5 mV at 5 V reference). Designers choose the COP431CN/NOPB in this role when the host board is through-hole, the firmware is already written for the COP serial protocol, and a modern surface-mount ADC would force an unwanted board redesign.
Recomendado
Microcontroller Analog Input Expansion
The COP431CN/NOPB is frequently used to add an analog input channel to microcontrollers that lack an on-board ADC, especially legacy COP8 and 8051-family devices still deployed in long-lifecycle equipment. The serial interface frees up GPIO that would otherwise be consumed by an 8-bit parallel ADC bus (11 pins), letting the host MCU dedicate those pins to digital I/O. With a typical conversion time in the low microseconds and a CS-driven conversion start, the part is well matched to polled analog-read firmware loops. Designers choose the COP431CN/NOPB over a modern surface-mount ADC when the existing PCB is through-hole, the firmware is COP-protocol-aware, or a socketed DIP-8 is required for field replacement.
Recomendado
Portable Battery-Powered Measurement
The COP431CN/NOPB is suitable for handheld measurement instruments such as digital multimeters, portable gas detectors, and field-test equipment because its single-channel SAR core delivers deterministic conversion latency at very low quiescent current, allowing the host MCU to put the ADC in standby between conversions and wake it on demand. With a single +5 V supply and an external low-power reference, the part supports battery-powered designs that must minimize quiescent drain while still providing 8-bit (256-step) measurement resolution. Designers prefer the COP431CN/NOPB in portable applications when the analog signal bandwidth is below a few kilosamples per second and absolute accuracy must hold across the commercial 0-70 C temperature range.
Recomendado
Education and Development Platforms
The COP431CN/NOPB is widely used in university labs, maker projects, and embedded-systems training kits because the DIP-8 through-hole package seats cleanly into a breadboard or IC socket, allowing students to wire and probe every ADC signal with standard 0.1-inch headers. The simple 3-wire serial protocol (CS, CLK, DOUT) is easy to teach: students toggle CS low, generate clocks on a GPIO pin, and read the conversion result one bit at a time on the falling clock edge. The 8-bit resolution (256 LSBs of full-scale range) is pedagogically clean - quantization error is exactly one part in 256, easy to compute by hand. Choose the COP431CN/NOPB when teaching fundamentals; upgrade to a 12-bit modern ADC for senior projects that demand higher resolution.
Recomendado
Instrumentation Front Panel Readout
The COP431CN/NOPB serves the analog front end of laboratory instrumentation, including bench-top signal sources, panel meters, and process-calibration equipment, where it digitizes analog signals from front-panel potentiometers, reference sources, or external sensor inputs. The deterministic SAR conversion latency means the host controller can synchronize ADC reads with display refresh, eliminating the flicker that plagues continuously-converting ADCs. The DIP-8 package and commercial temperature grade suit the controlled thermal environment of an instrument chassis, and the on-chip clock removes one source of analog noise by eliminating a high-impedance clock trace. Select the COP431CN/NOPB in this role when a stable 8-bit conversion is sufficient and the chassis accepts through-hole parts on a backplane PCB.
Recomendado
Automotive Aftermarket and Hobbyist Modules
Although the COP431CN/NOPB itself is commercial-grade and not AEC-Q100 qualified, hobbyist modules, retro automotive accessories (vintage gauge digitizers, classic-car sensor add-ons), and aftermarket telemetry boards frequently adopt the part because of its DIP-8 ease of integration and its compatibility with the COP8 MCU family used in legacy automotive ECUs. Designers wire the COP431CN/NOPB between a sensor (oil pressure, temperature, voltage) and a COP8 or 8051 host to digitize a single analog channel for display on a dashboard readout. The Pb-free NOPB finish supports modern RoHS-compliant hobby PCBs, while the through-hole pins suit the hand-soldered assemblies common in aftermarket kits. Choose the COP431CN/NOPB for non-safety automotive modules; for safety-critical paths, select an AEC-Q100 qualified modern ADC instead.
Recomendado
Resumo dos produtos recomendados
Dados de referência de engenharia para COP431CN/NOPB — comparação, orientação de projeto e informações de conformidade.
Guia de seleção
Comparação com alternativas
| Parâmetro | Este produto | COP431CN | ADC0848BCN/NOPB |
|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | PDIP-8 (DIP-8) | PDIP-8 (DIP-8) - same | PDIP-20 - different |
| Resolution | 8 bit | 8 bit | 8 bit |
| Channels | 1 | 1 | 8 |
| Interface | Serial (3-wire: CS, CLK, DOUT) | Serial (3-wire) | Parallel/serial |
| On-chip Clock | Yes | Yes | Yes |
| Lead Finish | Pb-free (NOPB) | SnPb (non-NOPB) | Pb-free (NOPB) |
| RoHS Compliance | Compliant | Non-compliant | Compliant |
| Lifecycle Status | Active | Active | Active |
Principais diferenciais
- DIP-8 through-hole footprint with internal clock (vs ADC0831CCWM)
- Smallest-footprint 8-bit SAR with 3-wire interface (vs ADC0848BCN/NOPB)
- Pb-free NOPB finish supports modern RoHS assembly (vs COP431CN (non-NOPB))
Notas de projeto
The COP431CN/NOPB requires a clean +5 V (VDD) supply and a stable external reference voltage on the VREF pin. Decouple VDD to GND with a 0.1 uF ceramic capacitor placed within 5 mm of the VDD pin and a 10 uF bulk capacitor at the regulator output. For VREF, use a low-noise reference such as the TL431ACDBZR (2.495 V shunt reference) bypassed with a 0.1 uF ceramic in parallel with a 10 uF electrolytic; this keeps the LSB step (VREF/256, e.g. 19.5 mV at 5 V reference) stable across the commercial 0-70 C range.
Place the COP431CN/NOPB close to the analog input source to minimize trace-induced noise pickup, and route the analog VIN trace away from digital lines such as CLK and DOUT. Use a ground plane on the bottom layer and stitch vias around the analog input to form a guard trace; this keeps the 8-bit (256-LSB) quantization noise below 1 LSB. For through-hole DIP-8 layouts, keep the analog ground return on a star-ground topology that ties back to the VDD decoupling capacitor before joining the digital ground.
Drive the serial clock (CLK) at a rate that respects the minimum high and low timing in the datasheet (typically a few MHz). Source-terminate the CLK trace with a series resistor of 33-100 ohm near the COP431CN/NOPB CLK pin if the MCU-to-ADC trace exceeds 50 mm, to prevent ringing and double-clocking. Capture DOUT on the falling CLK edge for stable reads; if the host samples on the rising edge, add a small delay (one NOP instruction in firmware) to avoid metastable reads.
Do not leave the VREF pin floating - this causes conversion results to drift unpredictably. Do not exceed the absolute-maximum analog input voltage (typically VDD + 0.3 V); clamp the analog input with a TVS diode or Schottky diode if the source can overshoot. Do not connect CS permanently low - the COP431CN/NOPB requires a CS rising edge to start a new conversion; tying CS low disables the conversion-start path. Finally, verify the reference voltage range is within the part's specified VREF input range (typically 0 V to VDD) before applying power.
Informações de conformidade
NOPB suffix per TI nomenclature indicates lead-free (Pb-free) matte-tin plating and RoHS compliance. Part is not AEC-Q100 qualified - not intended for safety-critical automotive applications. Originally released by National Semiconductor (now part of Texas Instruments).
