ADC0820BCWMX - 8-Bit 1.5µs Half-Flash ADC w/ T/H | Texas Instruments
部品番号: ADC0820BCWMX ✓ 生産中| 数量 | 単価 | 小計 |
|---|---|---|
| 1 | $3.42 | $3.42 |
| 10 | $3.08 | $30.80 |
| 100 | $2.74 | $274.00 |
| 500 | $2.41 | $1,205.00 |
| 1,000 | $2.15 | $2,150.00 |
| 2,500 | $1.89 | $4,725.00 |
ADC0820BCWMX 概要
A half-flash ADC is a parallel type of analog-to-digital converter that uses two 4-bit flash sub-converter stages rather than a full 256-latch comparator array, dramatically reducing die area, power consumption, and cost versus a true flash converter while still achieving sub-microsecond per-code sampling. Within the broader data-converter hierarchy, the ADC0820 sits at the low-resolution high-speed node: it is a successive-approximation-class part on the throughput axis (faster than most SAR), yet simpler and cheaper than a true flash ADC. It belongs to the power-management-and-conversion family of mixed-signal data-acquisition ICs.
The half-flash architecture performs a coarse 4-bit MSB conversion, then a fine 4-bit LSB conversion around the residue, producing a complete 8-bit code in two clock edges. Key features include 0 V to +5 V analog input range, on-chip track/hold eliminating the need for an external sample capacitor, ratiometric reference inputs for ratiometric transducers, and TTL-compatible digital outputs. Power dissipation is approximately 75 mW typical, and the device is specified for 0°C to +70°C (commercial) or −40°C to +85°C (industrial) operation depending on grade.
Typical applications include digital-panel meters, process control front ends, microcontroller analog input expansion, video digitizing at low bandwidth, instrumentation, and portable data loggers where high sample rate and low cost matter more than 12-bit precision. The wide SOIC-20 footprint also eases hand-prototyping and breadboard integration compared with smaller DFN/QFN alternatives.
When using this device, ensure the analog input driving bandwidth exceeds the ADC's input bandwidth, place a 0.1 µF decoupling capacitor directly at VCC, and route the analog/digital grounds with a star-ground or split-plane layout to avoid digital-noise coupling into the comparator ladder.
ドロップイン代替品: ADC0820BCWMX — 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:
ADC0820BCWMX/NOPB
✅ ドロップイン📋 参考代替品（カタログ未掲載）
TLC0820AIDWR
✅ ドロップイン📋 参考代替品（カタログ未掲載）
TLC0820ACDWG4
✅ ドロップイン📋 参考代替品（カタログ未掲載）
ADC0820BCWM
✅ ドロップイン ⚠️ 仕様未検証📋 参考代替品（カタログ未掲載）
ADC0820CCWMX/NOPB
✅ ドロップイン ⚠️ 仕様未検証📋 参考代替品（カタログ未掲載）
ADC0820BCVX/NOPB
✅ ドロップイン📋 参考代替品（カタログ未掲載）
ADC0820BCWMX 最大定格＆電気的特性
| Number of Bits | 8 |
| サンプリングレート | 667 kSPS (RD mode) |
| Conversion Time | 1.5 µs typical |
| Architecture | Half-Flash (two-flash) with Track/Hold |
| Number of Input Channels | 1 |
| Input Type | Single-Ended |
| Analog Input Range | 0 V to VREF(+) (0 V to +5 V with VREF = +5 V) |
| 基準電圧 | VREF(+) = +5 V, VREF(−) = GND (ratiometric) |
| Supply Voltage (VCC) | +5 V typical |
| Power Dissipation | 75 mW typical |
| Data Interface | Parallel (8-bit), microprocessor compatible (RD / WR-RDM modes) |
| 動作温度範囲 | 0°C to +70°C (commercial grade; suffix-dependent) |
| パッケージ / ケース | 20-SOIC (DW) wide-body, 7.50 mm |
| 実装タイプ | Surface Mount |
| RoHS ステータス | Compliant (NOPB suffix); non-compliant otherwise |
ADC0820BCWMX ピン構成
| ピン 1 | DB7 — Data output bit 7 (MSB) |
| ピン 2 | DB6 — Data output bit 6 |
| ピン 3 | DB5 — Data output bit 5 |
| ピン 4 | DB4 — Data output bit 4 |
| ピン 5 | DB3 — Data output bit 3 |
| ピン 6 | DB2 — Data output bit 2 |
| ピン 7 | DB1 — Data output bit 1 |
| ピン 8 | DB0 — Data output bit 0 (LSB) |
| ピン 9 | RD — Read strobe (interface mode select) |
| ピン 10 | GND — Digital ground |
| ピン 11 | VIN — Analog input (single-ended) |
| ピン 12 | VREF(+) — Reference voltage positive (typically +5 V) |
| ピン 13 | VREF(-) — Reference voltage negative (typically GND) |
| ピン 14 | AGND — Analog ground |
| ピン 15 | WR — Write strobe (start conversion in WR mode) |
| ピン 16 | INT — Conversion complete / interrupt output |
| ピン 17 | OF — Overflow flag (active low) |
| ピン 18 | DM — Mode select (RD vs WR-RDM) |
| ピン 19 | CL — Conversion clock input |
| ピン 20 | VCC — +5 V supply voltage |
主な用途
ADC0820BCWMX の用途: 6 件s: Microcontroller Analog Input Expansion, Digital Panel Meter and Instrumentation, Process Control Front End, Video and Audio Sampling (Low Bandwidth), Portable Data Logger Front End, Portable / Handheld Diagnostic Tool.
Microcontroller Analog Input Expansion
The ADC0820BCWMX is a classic solution for adding an 8-bit high-speed analog input channel to legacy 8-bit microcontrollers (8051, Z80, 68HC11) without built-in ADC. Its 1.5 µs conversion and TTL-compatible parallel interface tie directly to the external data bus in just a handful of glue logic, and the 667 kSPS sample rate comfortably outpaces SAR converters used in many legacy designs. At 0-5 V single-ended input, it accepts ratiometric transducer outputs directly, making it ideal for temperature, strain-gauge, and process-voltage interfaces in industrial controllers. The wide-body SOIC-20 also allows easy hand-prototyping on a 0.1 inch-pitch breadboard adapter. According to TI datasheet, the WR-RDM mode lets a single I/O line start a conversion and read back the result without bus arbitration, ideal for polled microcontroller firmware.
おすすめ
Digital Panel Meter and Instrumentation
Digital-panel meters (DPMs) and 3.5-digit panel instrumentation demand fast, low-cost conversion of transducer voltages into 8-bit or 12-bit displays, and the ADC0820BCWMX fits the entry-level segment perfectly. Its ratiometric reference inputs let designers use the panel-meter reference supply and the transducer excitation supply together, eliminating gain error from the supply drift. The 1.5 µs conversion allows >100 conversions per update for moving averages to suppress mains-frequency noise. With 75 mW typical dissipation and SOIC-20 footprint, the part survives thermally inside sealed meter enclosures. The half-flash architecture provides a clean code-stability performance needed for stable reading displays. According to TI datasheet typical applications, the ADC0820 family was originally designed for DPM and instrumentation front-ends.
おすすめ
Process Control Front End
Process-control systems (loop controllers, valve positioners, 4-20 mA receivers) frequently digitize 0-5 V or 0-10 V transducer signals at hundreds of samples per second for PID feedback. The ADC0820BCWMX provides 667 kSPS headroom so designers can oversample to reject 50/60 Hz line noise and feed a stable feedback signal to the controller. Its single +5 V supply simplifies isolated supply design using a 5 V dc/dc, and the parallel bus interface drops directly into legacy process-control ASICs. Operating from 0-70°C (or -40 to +85°C with the ADC0820CCWMX/NOPB grade), it covers most factory-floor temperature windows. The half-flash architecture provides deterministic latency suitable for closed-loop control without DSP-grade ADCs.
おすすめ
Video and Audio Sampling (Low Bandwidth)
The ADC0820BCWMX's 667 kSPS sample rate makes it suitable for digitizing low-bandwidth composite video (NTSC/PAL line-rate applications) or for wideband audio sampling at 44.1 kSPS with significant oversampling. Its on-chip track/hold ensures accurate sampling of rapidly varying signals without external sample caps, simplifying video digitizer designs for surveillance DVRs, scan converters, and waveform monitors. The half-flash 1.5 µs conversion provides excellent phase stability in coherent-sampling systems. The wide SOIC package eases PCB layout of high-frequency analog-input traces. According to TI datasheet, the part retains ±0.5 LSB linearity across the analog input range, sufficient for low-cost video scopes.
おすすめ
Portable Data Logger Front End
Battery-powered data loggers for environmental monitoring, soil-moisture recording, and remote telemetry need an ADC that samples fast enough to capture transient events but draws minimal power. The ADC0820BCWMX (or its lower-power TLC0820 sibling) fits this profile when powered intermittently by a duty-cycled 5 V rail. At 75 mW typical dissipation, a single channel can sample intermittently for days on a 1 Ah battery. The on-chip track/hold eliminates the external sample cap that would otherwise add leakage, and the SOIC-20 package is rugged enough for field-deployed enclosures. Engineers may place the ADC behind a low-power analog MUX to expand channels without dedicated ADC per channel. The 0-5 V input range accepts ratiometric sensor bridges directly.
おすすめ
Portable / Handheld Diagnostic Tool
Handheld diagnostic instruments (automotive scan tools, multimeter accessories, field-service testers) need 8-bit conversion at hundreds of samples per second for waveform capture and transducer readout, and the ADC0820BCWMX meets that need without breaking BOM cost. Its parallel interface pairs well with low-cost 8051-class microcontrollers that lack ADC peripherals, and its SOIC-20 wide-body package is rugged under mechanical shock. With its half-flash 1.5 µs conversion, designers can sample signals up to several hundred kHz, perfect for ignition-pickup, transducer waveform, and vibration diagnostics. The on-chip track/hold ensures clean samples on rapidly varying inputs. The legacy TI part is well documented in the original datasheet, with hundreds of reference designs available from third-party automotive tool vendors.
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: ADC0820BCWMX — 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 | ADC0820BCWMX/NOPB | TLC0820AIDWR | TLC0820ACDWG4 | ADC0820CCWMX/NOPB |
|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 20-SOIC (DW) | 20-SOIC (DW) - same | 20-SOIC (DW) - same | 20-SOIC (DW) - same | 20-SOIC (DW) - same |
| Resolution | 8 bits | 8 bits | 8 bits | 8 bits | 8 bits |
| Sampling Rate | 667 kSPS (RD mode) | 667 kSPS | ~667 kSPS (LinCMOS) | ~667 kSPS (LinCMOS) | 667 kSPS |
| Conversion Time | 1.5 µs | 1.5 µs | 1.5 µs | 1.5 µs | 1.5 µs |
| Architecture | Half-flash with T/H | Half-flash with T/H | Half-flash with T/H (LinCMOS) | Half-flash with T/H (LinCMOS) | Half-flash with T/H |
| RoHS Compliance | Order NOPB suffix for RoHS | RoHS compliant | RoHS compliant | RoHS compliant | RoHS compliant |
| Operating Temperature | 0°C to +70°C | 0°C to +70°C | -40°C to +85°C | 0°C to +70°C | -40°C to +85°C |
| Power Dissipation | 75 mW typical | 75 mW | ~25 mW (LinCMOS low-power) | ~25 mW | 75 mW |
主な差別化要因
- On-chip track-and-hold eliminates external sample capacitor （vs ADC0804LCWMX (SAR without T/H))
- Half-flash architecture: 1.5 µs vs ~10 µs for SAR ADCs （vs ADC0804LCWMX (SAR ADC))
- Direct microprocessor bus interface with RD mode （vs TLC0820AIDWR (LinCMOS, lower-power))
設計ノート
Place a 0.1 µF ceramic decoupling capacitor as close as possible to the VCC pin (pin 20) and a 10 µF bulk capacitor at the supply entry point. The 20-pin SOIC wide-body package has sufficient lead pitch to allow vias directly under the part for power and ground, but keep the analog input trace (pin 11) routed away from digital outputs DB0-DB7. Use a star-ground or split-ground plane with the analog ground tied to digital ground only at a single point near the AGND pin. According to TI datasheet, proper decoupling reduces digital-noise coupling that can otherwise appear as ±0.5 LSB code flicker in the lowest bits.
Do not drive the analog input (VIN) above VREF(+) or below VREF(−) - the analog input protection diodes clamp but will inject error current into the input. Ensure the driving amplifier can slew fast enough for the ADC0820BCWMX input (full-scale >90 kHz analog input bandwidth typical). When using RD mode, leave the WR pin and DM pin tied appropriately per datasheet timing diagrams, otherwise the converter may stall or output garbage. Ensure VREF(+) is a low-impedance reference (op-amp buffer) because the ADC0820 draws transient current during the second flash phase that would otherwise sag a high-impedance reference and add gain error.
The ADC0820BCWMX's parallel 8-bit output bus can generate simultaneous switching noise (SSN) at every code boundary, so route the output bus with matched trace lengths and a series-termination resistor at each output (33-100 ohm) when driving a long cable or a non-orthogonal bus. Keep the conversion clock (CL pin) routed short and away from analog input traces. The on-chip track/hold eliminates the external hold capacitor, but the input still presents a switched-capacitor load of ~10 pF that the driving amplifier must settle within the acquisition window. A wide-bandwidth op-amp such as OPA227 or equivalent at the input is recommended for low-distortion sampling above 50 kHz analog input frequency.
コンプライアンス情報
ADC0820BCWMX/NOPB is RoHS compliant with lead-free matte-tin finish. Plain ADC0820BCWMX (without NOPB) uses legacy SnPb finish and is not RoHS. AEC-Q100 not applicable - automotive engineers should consult TI's AEC-Q100-qualified ADC portfolio. REACH conflict minimization follows TI standard policy.
