ADC0805LCN/NOPB - 8-Bit μP-Compatible SAR ADC | Texas Instruments
部品番号: ADC0805LCN/NOPB ✓ 生産中| 数量 | 単価 | 小計 |
|---|---|---|
| 1 | $6.42 | $6.42 |
| 10 | $5.78 | $57.80 |
| 100 | $5.14 | $514.00 |
| 500 | $4.6 | $2,300.00 |
| 1,000 | $4.1 | $4,100.00 |
ADC0805LCN/NOPB 概要
An SAR (Successive Approximation Register) ADC is a type of analog-to-digital converter that performs binary-search conversions using an internal comparator and DAC. Each conversion takes a fixed number of clock cycles regardless of input amplitude, giving SAR ADCs deterministic latency and making them ideal for multiplexed data-acquisition systems. SAR ADCs sit in the broader hierarchy of data converter (ADC/DAC) -> data acquisition IC -> mixed-signal semiconductor, balancing speed, accuracy, and simplicity.
Key features include 8-bit resolution, a single-ended analog input, differential input capability, on-chip clock, and tri-state output latches that directly drive microprocessor data buses (such as the NSC800 and INS8080A derivative control buses). The differential potentiometric ladder ensures zero-scale full-scale ratiometric operation, eliminating the need for precision external reference components when used with ratiometric sensors.
The device architecture uses a switched-capacitor DAC and a CMOS comparator inside the SAR loop, sampled under an internal clock derived from an external R/C network. A built-in track-and-hold captures the input at the start of each conversion; the part then produces a tri-state parallel byte suitable for direct connection to 8-bit microprocessor data buses. Power consumption is low because the converter powers down between conversions when driven by the WR/RD handshake lines.
Typical applications include process-control data loggers, portable instrumentation, ratiometric sensor digitisation (strain gauges, thermistors, potentiometric position sensors), digital panel meters, and embedded microprocessor analog front ends. Industrial-grade operating temperature range of -40 °C to +85 °C makes the part suitable for factory-floor equipment and outdoor enclosures.
When designing-in is planned, set the clock resistor and capacitor on pins CLK R and CLK IN to the values recommended in the manufacturer datasheet typical-application section to achieve the desired conversion rate. Tie CS and RD low for free-running conversion, or use them to synchronise acquisition to a microcontroller bus cycle. Decouple V+ with a 0.1 µF ceramic placed within 10 mm of the supply pin to limit digital switching noise.
This page synthesizes distributor pricing, drop-in same-package alternatives, and practical design notes that complement the manufacturer datasheet's typical-application circuit by adding validated cross-reference data and PCB-level decoupling guidance.
ドロップイン代替品: ADC0805LCN/NOPB — 同一パッケージでピン互換。PCBの作り直しが必要な異なるパッケージの部品は除外されています。
クイック比較ツール — 並列比較する代替部品を選択:
ADC0804LCN/NOPB
✅ ドロップイン📋 参考代替品（カタログ未掲載）
ADC0801LCN/NOPB
✅ ドロップイン📋 参考代替品（カタログ未掲載）
ADC0802LCN/NOPB
✅ ドロップイン📋 参考代替品（カタログ未掲載）
ADC0803LCN/NOPB
✅ ドロップイン📋 参考代替品（カタログ未掲載）
ADC0805LCJ
✅ ドロップイン📋 参考代替品（カタログ未掲載）
ADC0805LCN/NOPB 最大定格＆電気的特性
| 分解能 | 8 bits |
| Number of Channels | 1 |
| Conversion Architecture | SAR (Successive Approximation) |
| Data Interface | Parallel |
| Analog Input Type | Single-ended / Differential |
| 電源電圧 | 4.5 V to 6.5 V (typical 5 V) |
| 入力電圧範囲 | 0 V to 5 V (ratiometric with VREF) |
| 動作温度 | -40 °C to +85 °C |
| パッケージ / ケース | 20-DIP (0.300 in, 7.62 mm) |
| 実装タイプ | Through-Hole |
| Packaging | Tube |
| ピン数 | 20 |
| Reference Type | External (ratiometric operation supported) |
| Output Latch | Tri-state, 8-bit parallel |
| RoHS ステータス | Compliant (NOPB suffix) |
| Lead-Free / Pb-Free | Yes (NOPB suffix) |
| MSLレベル | 1 (not moisture sensitive for PDIP) |
ADC0805LCN/NOPB ピン構成
| ピン 1 | CS — Chip Select (active low) |
| ピン 2 | RD — Read (active low) |
| ピン 3 | WR — Write (active low) |
| ピン 4 | CLK IN — Clock input (internal clock generator) |
| ピン 5 | INTR — Interrupt output (active low) |
| ピン 6 | VIN+ — Analog input, non-inverting |
| ピン 7 | VIN- — Analog input, inverting |
| ピン 8 | AGND — Analog ground |
| ピン 9 | VREF/2 — Reference voltage / 2 input for ratiometric operation |
| ピン 10 | DGND — Digital ground |
| ピン 11 | DB7 — Tri-state data output bit 7 (MSB) |
| ピン 12 | DB6 — Tri-state data output bit 6 |
| ピン 13 | DB5 — Tri-state data output bit 5 |
| ピン 14 | DB4 — Tri-state data output bit 4 |
| ピン 15 | DB3 — Tri-state data output bit 3 |
| ピン 16 | DB2 — Tri-state data output bit 2 |
| ピン 17 | DB1 — Tri-state data output bit 1 |
| ピン 18 | DB0 — Tri-state data output bit 0 (LSB) |
| ピン 19 | CLK R — Clock RC network (sets conversion rate) |
| ピン 20 | V+ — Positive supply (5 V nominal) |
主な用途
ADC0805LCN/NOPB の用途: 7 件s: Process-Control Data Logger, Ratiometric Sensor Digitisation (Strain-Gauge / Potentiometer), Digital Panel Meter Front End, Embedded Microcontroller Analog Front End (8051 / Z80), Portable Battery-Powered Instrumentation, Industrial Automation / PLC Analog Input Module, Automotive / Off-Road Sensor Digitisation (Legacy).
Process-Control Data Logger
The ADC0805LCN/NOPB suits process-control data loggers that digitise 0-5 V analog sensor outputs from 4-20 mA current-loop receivers or potentiometric position sensors. Its single 5 V supply, parallel tri-state output, and direct microprocessor bus interface allow straightforward connection to legacy 8-bit controllers (8048, 8051, Z80) without an external address latch, while the ratiometric potentiometric ladder cancels supply-induced gain error. The -40 °C to +85 °C industrial operating range covers factory-floor enclosures and outdoor cabinets.
おすすめ
Ratiometric Sensor Digitisation (Strain-Gauge / Potentiometer)
The ADC0805LCN/NOPB is well matched to ratiometric sensor digitisation, where the excitation voltage and the ADC reference are derived from the same 5 V rail. This topology eliminates absolute supply error and preserves 8-bit accuracy even as the supply drifts, which is critical for strain-gauge bridges, thermistor dividers, and potentiometric position sensors in weighing scales and machine-tool feedback. The differential potentiometric ladder plus differential analog inputs reject common-mode offsets in the bridge.
おすすめ
Digital Panel Meter Front End
Front-end digitisation for digital panel meters uses the ADC0805LCN/NOPB to convert a 0-5 V or ±5 V analog display signal into an 8-bit parallel code that drives a 3.5-digit BCD/7-segment decoder/display chain. The on-chip track-and-hold settles in one clock cycle and the parallel output latches directly into a decoder such as the CD4511, eliminating an external sample/hold and simplifying the bill of materials. Designers should route CLK R/CLK IN with short traces and place a 0.1 µF V+ decoupling capacitor within 10 mm of pin 20.
おすすめ
Embedded Microcontroller Analog Front End (8051 / Z80)
Embedded 8-bit microcontrollers such as the 8051 and Z80 historically required an external parallel ADC because on-chip ADCs were unavailable. The ADC0805LCN/NOPB plugs directly into the external memory bus using CS, RD, and WR handshake signals, producing an 8-bit code on DB0-DB7 with no glue logic. Designers connect INTR to an external interrupt pin so the firmware only services the ADC when conversion is complete, avoiding busy-wait polling at higher conversion rates.
おすすめ
Portable Battery-Powered Instrumentation
The ADC0805LCN/NOPB operates from a single 5 V rail and supports a low-power mode where the part automatically powers down between conversions when CS and WR are toggled per the datasheet handshake diagram. This makes the device suitable for portable handheld instrumentation such as digital multimeters, environmental loggers, and battery-powered medical monitors where standby current must remain low. Use a low-quiescent 5 V LDO (for example an LP2985) to extend battery life between measurements.
おすすめ
Industrial Automation / PLC Analog Input Module
Industrial PLC analog input modules use the ADC0805LCN/NOPB to digitise 8 isolated or non-isolated 0-10 V analog channels via an external analog multiplexer, with the differential input supporting ±5 V true bipolar measurement when paired with an external resistor-divider front end. The wide -40 °C to +85 °C industrial operating range and the 20-pin PDIP through-hole package simplify conformal-coated module assemblies and field-serviceable repairs. Each conversion completes in microseconds, supporting aggregate throughput above 10 kHz across a multiplexed channel scan.
おすすめ
Automotive / Off-Road Sensor Digitisation (Legacy)
The ADC0805LCN family is used in legacy automotive test equipment, off-road vehicle sensor modules, and aftermarket diagnostic tools that read potentiometric throttle-position, fuel-level, and temperature sensors. The 5 V single-supply operation and parallel bus interface suit older 8-bit microcontrollers that lack integrated ADC peripherals. For new automotive designs requiring AEC-Q100 qualification, modern automotive-grade SAR ADCs such as the ADS7253 should be selected instead, but the ADC0805LCN/NOPB remains a cost-effective drop-in for existing production lines and test fixtures.
おすすめ
おすすめ製品の概要
エンジニアリング参考データ: ADC0805LCN/NOPB — 比較、設計ガイダンス、コンプライアンス情報。
選定ガイド
代替品との比較
| パラメータ | この製品 | ADC0804LCN/NOPB | ADC0801LCN/NOPB | ADC0802LCN/NOPB | ADC0803LCN/NOPB | ADC0805LCJ |
|---|---|---|---|---|---|---|
| Package | 20-DIP (0.300 in, 7.62 mm) | 20-DIP (0.300 in, 7.62 mm) - same | 20-DIP (0.300 in, 7.62 mm) - same | 20-DIP (0.300 in, 7.62 mm) - same | 20-DIP (0.300 in, 7.62 mm) - same | 20-CDIP (0.300 in) - same footprint, ceramic |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Resolution | 8 bits | 8 bits | 8 bits | 8 bits | 8 bits | 8 bits |
| Conversion Architecture | SAR (Successive Approximation) | SAR | SAR | SAR | SAR | SAR |
| Data Interface | Parallel (8-bit, tri-state) | Parallel (8-bit, tri-state) | Parallel (8-bit, tri-state) | Parallel (8-bit, tri-state) | Parallel (8-bit, tri-state) | Parallel (8-bit, tri-state) |
| Linearity (INL/DNL) | ±1 LSB | ±1 LSB | ±1/4 LSB | ±1/2 LSB | ±1/2 LSB | ±1 LSB |
| Operating Temperature | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -55 °C to +125 °C (military) |
| Supply Voltage | 5 V typical (4.5 V to 6.5 V) | 5 V typical | 5 V typical | 5 V typical | 5 V typical | 5 V typical |
| Package Type / Mounting | Plastic DIP, through-hole | Plastic DIP, through-hole | Plastic DIP, through-hole | Plastic DIP, through-hole | Plastic DIP, through-hole | Ceramic DIP (CDIP), through-hole |
| RoHS / Lead-Free | Yes (NOPB suffix) | Yes (NOPB suffix) | Yes (NOPB suffix) | Yes (NOPB suffix) | Yes (NOPB suffix) | Depends on suffix (J often non-RoHS) |
主な差別化要因
- Single 5 V supply with ratiometric differential potentiometric ladder （vs Generic 8-bit ADC requiring ±5 V or external precision reference)
- Direct parallel microprocessor bus interface with tri-state latches （vs Modern SPI/I2C-interface 8-bit ADCs (e.g., ADC0801S040TS/C1))
- Five-member same-package pin-compatible family (ADC0801-05) （vs Single linear- or linearity-grade part in 20-DIP)
- On-chip track-and-hold and clock generator （vs Discrete sample-and-hold + external oscillator designs)
設計ノート
Decouple V+ (pin 20) with a 0.1 µF ceramic capacitor placed within 10 mm of the supply pin, plus a bulk 10 µF electrolytic or tantalum on the same 5 V rail. The ADC0805LCN/NOPB contains internal analog and digital supplies; sharing a noisy digital rail directly with the analog V+ pin without adequate decoupling can introduce 1-2 LSB of conversion noise. AGND (pin 8) and DGND (pin 10) should tie to a single ground plane with a star-point connection under the IC to avoid ground-loop coupling.
Route the analog inputs (VIN+, VIN-) and VREF/2 traces with short, guarded paths and avoid running them parallel to digital bus lines (DB0-DB7, CS, RD, WR). The internal clock generator on pins CLK IN and CLK R should be configured with the resistor-capacitor values from the datasheet typical-application section (typically R = 10 kΩ, C = 150 pF for ~640 kHz clock). Place the CLK R capacitor close to the IC; long CLK R traces pick up digital switching noise and degrade conversion accuracy.
Do not leave CS floating - tie it to GND for free-running mode or to a microcontroller GPIO for synchronised acquisitions. The INTR (interrupt, pin 5) output is active low and must be pulled high with a 10 kΩ resistor if the host does not provide an internal pull-up, otherwise spurious interrupts may occur. Avoid driving VREF/2 with a source impedance above the datasheet maximum, as this introduces gain error. For ratiometric operation, derive VREF/2 directly from the same 5 V rail that powers the sensor bridge.
When connecting DB0-DB7 directly to an 8-bit microcontroller data bus, ensure the microcontroller firmware does not drive DB0-DB7 as outputs while RD is asserted (active low); bus contention can cause the ADC output buffers to source/sink excessive current. If bus contention is possible, gate the host's data-bus output enable with CS so the host tri-states its data pins before the ADC drives DB0-DB7. Adding 10 kΩ series resistors on each DB line helps protect against contention in legacy designs.
The ADC0805LCN/NOPB consumes low supply current (single-digit mA) at 5 V and does not require a heatsink in normal operation. However, in high-density PLC modules or sealed enclosures where ambient exceeds +70 °C, derate operating temperature and verify the ceramic-package variant (ADC0805LCJ) if available for your design. Conformal coating does not affect thermal performance for this part in through-hole PDIP-20 form factor.
コンプライアンス情報
NOPB suffix denotes Pb-free / RoHS-compliant packaging per Texas Instruments ordering nomenclature. Not AEC-Q100 qualified; for new automotive designs select AEC-Q100-qualified modern SAR ADCs. Halogen-free status not specified in verified data.
