ADC0820BCWM/NOPB - 8-Bit 667kSPS Half-Flash ADC | TI
MPN: ADC0820BCWM/NOPB ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.42 | $5.42 |
| 10 | $4.87 | $48.70 |
| 100 | $3.95 | $395.00 |
| 500 | $3.41 | $1,705.00 |
| 1,000 | $2.96 | $2,960.00 |
ADC0820BCWM/NOPB Overview
What is a half-flash ADC? A half-flash ADC, also called a two-step or subranging flash converter, is a type of analog-to-digital converter that performs an initial coarse flash conversion followed by a fine flash conversion on the residue. This architecture reduces the number of comparators required compared with a true flash ADC, lowering die area and power consumption while keeping conversion speed close to flash-class performance. The ADC0820 family belongs to the wider hierarchy of Nyquist-rate ADCs -> half-flash ADCs -> successive-approximation-class converters -> data-acquisition analog ICs -> signal-chain semiconductors, and typically finds use wherever an 8-bit micro-processor-compatible ADC is needed.
Key features include a single +5V supply operation with a 4.5V to 8V Vcc range, single-ended analog input with track-and-hold, and parallel microprocessor-compatible output data. The converter provides ratiometric conversion, accepts an external reference or supply-referenced operation, and supports both read-during-conversion and read-after-conversion timing modes for flexible processor interfacing. The wide SOIC-20 package simplifies prototyping and wave-solder PCB assembly.
The device uses a built-in track-and-hold amplifier that minimizes aperture uncertainty and enables accurate conversions on fast-moving input signals. Operating modes are selected via the MODE pin, allowing single-ended or differential-style conversion control without external sample/hold circuitry.
Typical applications include process control data acquisition, digital signal processing front-ends, portable instrumentation, video-digitizer auxiliary ADCs, and PC-based measurement boards that require an 8-bit, micro-processor-friendly ADC with a parallel bus interface. Industrial, scientific, and medical instrumentation that needs 0-70C commercial-grade operation also benefits from this part.
When designing with this converter, ensure the analog input source impedance is low enough to settle within the track time, and place a 0.1 microF decoupling capacitor directly on the Vcc pin. For best linearity, drive the analog input from a low-impedance buffer, and avoid switching large digital currents near the analog ground return.
This page synthesizes distributor pricing, verified drop-in alternatives, application-grade companion parts, and practical design notes not found in the bare manufacturer datasheet, helping engineers evaluate the ADC0820BCWM/NOPB for both new design and legacy support scenarios.
Drop-in alternatives for ADC0820BCWM/NOPB — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with ADC0820BCWM/NOPB (same form factor and footprint) — differing in Conversion Time, Data Interface, Mounting Type, Operating Temperature, Power Dissipation.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ADC0820CCWM/NOPB
✅ Drop-In📋 Reference alternative (not in catalog)
ADC0820BCWMX/NOPB
✅ Drop-In📋 Reference alternative (not in catalog)
ADC0820CCN/NOPB
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
TLC0820ACDW
✅ Drop-In📋 Reference alternative (not in catalog)
ADC0820BCV
✅ Drop-In✓ In Stock
$3.9 / Unit
View Datasheet →ADC0820BCWM/NOPB Maximum Ratings & Electrical Characteristics
| Resolution | 8 bit |
| Number of Inputs | 1 |
| Conversion Method | Half-Flash (two-step flash) |
| Conversion Time | 1.5 µs (max) |
| Sampling Rate | 667 kSPS |
| Data Interface | Parallel (microprocessor-compatible) |
| Input Configuration | Single-ended with on-chip Track/Hold |
| Supply Voltage (Vcc) | 4.5 V to 8 V (single supply) |
| Power Dissipation | 75 mW (typical) |
| Operating Temperature | 0 °C to +70 °C (commercial) |
| Temperature Grade | Commercial |
| Package / Case | 20-SOIC (WM), 0.295 inch / 7.50 mm body width |
| Mounting Type | Surface Mount, gull-wing leads |
| Pin Count | 20 |
| Packaging | Tube (manufacturer specified) |
| RoHS Status | Compliant (NOPB suffix) |
| Lead-Free / Halogen-Free | Lead-Free (NOPB) |
ADC0820BCWM/NOPB Pin Configuration
| Pin 1 | DB0 — Data output bit 0 (LSB) |
| Pin 2 | DB1 — Data output bit 1 |
| Pin 3 | DB2 — Data output bit 2 |
| Pin 4 | DB3 — Data output bit 3 |
| Pin 5 | DB4 — Data output bit 4 |
| Pin 6 | DB5 — Data output bit 5 |
| Pin 7 | DB6 — Data output bit 6 |
| Pin 8 | DB7 — Data output bit 7 (MSB) |
| Pin 9 | INT — Interrupt output (end-of-conversion) |
| Pin 10 | MODE — Mode selection: read-during-conversion vs read-after-conversion |
| Pin 11 | CS — Chip Select (active low) |
| Pin 12 | RD — Read input (active low) |
| Pin 13 | WR/RDY — Write / Ready output for converter start |
| Pin 14 | GND — Ground (analog/digital common) |
| Pin 15 | V+ — Positive analog input |
| Pin 16 | VREF — Voltage Reference input |
| Pin 17 | AGND — Analog Ground |
| Pin 18 | NC — Not connected (per datasheet) |
| Pin 19 | NC — Not connected (per datasheet) |
| Pin 20 | Vcc — Positive supply (4.5 V to 8 V) |
Typical Applications
ADC0820BCWM/NOPB is suitable for 6 applications: Process Control & Data Acquisition Systems, Digital Signal Processing (DSP) Front-End, Portable Instrumentation & Test Equipment, PC-Based Measurement & Data Logging Cards, Audio & Video Digitizer Auxiliary ADCs, Industrial Scientific & Medical (ISM) Front-End.
Process Control & Data Acquisition Systems
The ADC0820BCWM/NOPB's 667 kSPS sampling rate and 8-bit resolution make it a strong fit for process-control data-acquisition boards that read analog sensor outputs into a micro-processor bus. With 1.5 microsecond conversion time, the half-flash converter captures fast-changing inputs from pressure, flow, or temperature transducers while keeping 75 mW dissipation manageable in fan-less DIN-rail modules. The parallel output drops directly into 8051/PIC/AVR-style 8-bit data buses, removing glue logic. Use a low-impedance op-amp buffer ahead of the analog input and place a 0.1 µF decoupling cap on Vcc; the on-chip track-and-hold relaxes external sample-and-hold requirements, and the 4.5-8V supply accommodates 5V regulated industrial rails directly.
Recommended
Digital Signal Processing (DSP) Front-End
In DSP front-ends the ADC0820BCWM/NOPB acts as a fast 8-bit converter that feeds sampled data into a downstream DSP for FFT, filtering, or control-loop math. The 1.5 microsecond conversion supports sampling rates up to 667 kSPS, well above the Nyquist rate for many audio and vibration bands, and the parallel output flags eight bits per cycle so data flows to DSP or FPGA without serializing overhead. The on-chip track-and-hold keeps aperture uncertainty low, important when digitizing high-frequency components; designers can pair the converter with a low-pass input filter and run the DSP from the same 5V rail thanks to the 4.5-8V supply. Compared with a 16-bit SAR, the 8-bit half-flash is attractive when simplicity, speed and deterministic latency matter more than resolution.
Recommended
Portable Instrumentation & Test Equipment
Battery- and USB-powered handheld test gear benefits from the ADC0820BCWM/NOPB's 75 mW typical dissipation and single 5V supply, which simplifies power budgeting in portable enclosures. The 8-bit result is plenty for panel-meter readouts, audio-level meters, and diagnostic scopes that don't require 16-bit accuracy. Microprocessor-compatible parallel read/write timing lets a small MCU grab conversions directly without extra logic, and the 0-70C commercial range suits indoor lab and field environments. Industrial handheld builds can place the 20-SOIC on a compact 2-layer PCB with a precision reference, op-amp buffer, and backlight LCD driver — all tolerant of the part's 4.5-8V rail.
Recommended
PC-Based Measurement & Data Logging Cards
Plug-in ISA/PCI/PC-104 or modern MCU-based measurement cards use the ADC0820BCWM/NOPB as a fast 8-bit channel for general-purpose analog I/O. The wide SOIC-20 footprint handles hand-soldered prototypes as well as SMT reflow production runs, and the parallel-read interface maps cleanly to common 8-bit peripheral buses without additional latches. Channel switching can be handled upstream by an analog mux; the track-and-hold on the converter settles quickly enough that throughput is preserved when scanning multiple sources. With ratiometric capability, designers can use a TL431-based reference tied to the excitation rail for transducer bridge readouts, and the commercial temperature range suits indoor test racks and laboratory data loggers.
Recommended
Audio & Video Digitizer Auxiliary ADCs
Although the ADC0820BCWM/NOPB is a general-purpose half-flash ADC rather than an audio-specific part, its 667 kSPS rate comfortably oversamples 44.1 kHz audio and standard video sync levels, making it useful for auxiliary meter, VU, or sync-detection channels in mixed-signal audio/video products. The 8-bit quantizer provides enough steps for level metering and side-channel telemetry; designers pair it with quality op-amps ahead of the input to drive the analog pin. Wide SOIC keeps debug easy in mixed boards, and the parallel data flags integrate with MCU/MPU I/O so engineers can route status bits without re-architecting firmware. The 5V supply matches typical audio board rails and the 0-70C range suits consumer AV equipment operating indoors.
Recommended
Industrial Scientific & Medical (ISM) Front-End
The commercial 0-70C temperature grade of ADC0820BCWM/NOPB fits indoor industrial-automation, lab-instrumentation, and OEM medical-device front-ends where a fast 8-bit scan is acceptable. With its single +5V supply, 75 mW dissipation, and 1.5 microsecond conversion, the part serves as a quick sample-and-convert block in motor-control feedback loops, bench-top instrument sub-systems, or patient-monitor auxiliary channels. Wide SOIC pin spacing simplifies hand prototyping in regulated laboratories, and the parallel output simplifies interface code for 8-bit microcontrollers that monitor process variables. Designers should bias analog inputs from a low-noise reference and isolate digital returns; the half-flash architecture keeps conversion latency deterministic, which is essential in control-loop timing.
Recommended
Recommended Products Summary
Engineering reference data for ADC0820BCWM/NOPB — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ADC0820CCWM/NOPB | ADC0820BCWMX/NOPB | ADC0820CCN/NOPB | TLC0820ACDW | ADC0820BCV |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 20-SOIC (WM, 7.50 mm) | 20-SOIC (WM, 7.50 mm) - same | 20-SOIC (WM, 7.50 mm) - same | 20-SOIC (WM, 7.50 mm) - same | 20-SOIC (DW, 7.50 mm) - same | 20-SOIC (WM, 7.50 mm) - same |
| Resolution | 8 bit | 8 bit | 8 bit | 8 bit | 8 bit | 8 bit |
| Conversion Time | 1.5 µs | 1.5 µs | 1.5 µs | 1.5 µs | ~560 ns (faster) | 1.5 µs |
| Sampling Rate | 667 kSPS | 667 kSPS | 667 kSPS | 667 kSPS | ~1.78 MSPS (faster) | 667 kSPS |
| Conversion Method | Half-Flash | Half-Flash | Half-Flash | Half-Flash | Half-Flash (LinCMOS upgrade) | Half-Flash |
| Operating Temperature | 0 °C to +70 °C | 0 °C to +70 °C | 0 °C to +70 °C | 0 °C to +70 °C | 0 °C to +70 °C | 0 °C to +70 °C |
| Accuracy Grade | B (commercial, 0 to 70 °C) | C (tighter linearity, same range) | B (same die, reel pkg) | C (commercial 0-70 °C) | TLC0820A (LinCMOS family) | B (CERDIP/PDIP package code) |
Key Differentiators
- Half-flash architecture delivers 1.5 µs conversion with only 75 mW dissipation (vs ADC0804 (successive-approximation, ~10 µs))
- Higher accuracy 'C' grade available in pin-compatible 20-SOIC WM footprint (vs ADC0820CCWM/NOPB)
- On-chip track-and-hold eliminates external sample/hold cost (vs Discrete SAR + external T/H designs)
Design Notes
Decouple Vcc with a 0.1 microfarat ceramic capacitor placed as close as possible to the Vcc pin, ideally within 5 mm, to keep high-frequency digital switching noise out of the analog half-flash comparators. The ADC0820 specifies Vcc between 4.5 V and 8 V, with 5 V being the typical design value; avoid running the device near Vcc = 8 V unless the PCB layout can guarantee thermal dissipation under the 75 mW continuous load. If the converter is fed by a noisy regulator (e.g., a switching pre-regulator), insert a ferrite bead and bulk capacitor ahead of Vcc to keep ripple off the reference.
Place the analog input buffer (op-amp follower) within 10 mm of the V+ pin, and route the analog trace as a guard-traced differential pair separated from the parallel DB0-DB7 strobing lines. The ADC0820BCWM/NOPB's on-chip track-and-hold will faithfully sample any noise present at the V+ pin, so star-grounding analog and digital grounds into one decoupled point near the converter avoids ground-return noise on the AGND pin. If the design uses 5V digital logic on the same board, keep the digital traces on the opposite side of the PCB and avoid crossing the analog input trace.
Driving the V+ analog input from a high-impedance source is a common ADC0820BCWM/NOPB pitfall: the on-chip track-and-hold needs a low-impedance signal source (typically below 1 kohm) to settle within the track time. If your transducer has high output resistance, add a fast op-amp buffer (e.g., AD8552-class chopper) before the converter. Another frequent mistake is miswiring MODE: setting the wrong read-during-conversion / read-after-conversion mode can stall the CS/RD handshake; verify this against the timing diagrams in the TI datasheet. Finally, do not assume the part works above 70 °C — for industrial environments use the ADC0820CIWM (industrial) variant instead.
Compliance Information
NOPB suffix indicates lead-free RoHS-compliant construction as standard. AEC-Q100 grade not applicable — ADC0820BCWM/NOPB is commercial grade 0-70 C; for automotive designs use TI AEC-Q100 qualified parts such as ADC0820BCWM-Q1 (not in active mainstream catalog — verify with TI).
