ADC0820CCN/PB - 8-Bit 667kSPS Flash ADC w/ Track-Hold | TI
MPN: ADC0820CCN/PB ✓ Hoạt độngADC0820CCN/PB Tóm tắt
An analog-to-digital converter (ADC) is a data-acquisition integrated circuit that converts real-world continuous analog voltages into discrete digital codes that a microcontroller, microprocessor, or DSP can process. The 8-bit ADC0820 falls in the "moderate-resolution, high-speed" tier of the data-converter taxonomy: ADC -> successive-approximation / flash ADC -> data converter -> data-acquisition IC -> signal conditioning -> mixed-signal semiconductor. Semi-flash (or half-flash) converters like the ADC0820 use two parallel low-resolution flash stages to halve the number of comparators versus a true flash design while delivering comparable speed.
Key features include parallel CMOS-compatible output, an input range of 0V to 5V, a built-in sample-and-hold that allows full throughput on rapidly changing signals, and ratiometric operation when the reference is tied to the supply. The track-and-hold function ensures accurate conversion of fast analog transients without an external SHA, simplifying front-end design.
The semi-flash (two-step) architecture performs a coarse 4-bit conversion followed by a fine 4-bit conversion, generating the final 8-bit result in roughly 1.5 clock cycles. This topology yields low input capacitance and modest power consumption compared with true flash converters while avoiding the long acquisition times of successive-approximation ADCs.
Typical applications include digital voltmeters, panel meters and bench instrumentation, process-control analog front-ends, video digitizing at sub-Nyquist rates, disk-drive servo control loops, and µP-based data-logging boards. The DIP-20 footprint and parallel interface suit legacy 8-bit microcontrollers and replacement of obsolete ADC0820 sockets without board rework.
When designing with this part, place a 100 nF decoupling capacitor directly between V+ and GND as close to the pins as possible, and keep analog and digital grounds on a single low-impedance plane tied at one point. The reference input may be driven from a 2.5V precision reference or from the 5V supply for ratiometric conversions using bridge or resistive sensors.
This page synthesizes current distributor availability, drop-in alternatives in the DIP-20 footprint, and practical PCB design notes for the ADC0820 family that are not found in the manufacturer datasheet.
Bộ thay thế dễ dàng lắp đặt cho ADC0820CCN/PB — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với ADC0820CCN/PB (cùng hình factor và footprint) — khác nhau ở Architecture, Conversion Time, Mounting Type, Operating Temperature, Package.
ADC0820CCN
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
ADC0820CCN/NOPB
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
ADC0820CC/D
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →ADC0820BCV
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →ADC0820CCN/B+
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
LTC1099ACN#PBF
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
LTC1099CN#PBF
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
ADC0820CCN/PB Tỷ lệ tối đa & tính chất điện
| Manufacturer | Texas Instruments |
| Part Number | ADC0820CCN/PB |
| Độ phân giải | 8 bit |
| Conversion Rate | 667 kSPS (max) |
| Conversion Time | 2.5 us (max) |
| Number of Input Channels | 1 |
| Architecture | Semi-flash (two-step flash) |
| Điện áp cung cấp | 4.5 V to 8 V (5 V typical) |
| Phạm vi điện áp đầu vào | -0.1 V to 5.1 V |
| Track-and-Hold | Yes (internal) |
| Output Interface | 8-bit parallel (CMOS) |
| Nhiệt độ hoạt động | 0 C to +70 C (commercial) |
| Hộp | 20-pin PDIP (Plastic DIP, 0.300 inch) |
| Kiểu lắp đặt | Through-Hole |
| Temperature Grade | Commercial |
| Trạng thái RoHS | Compliant |
| Lead Free | Yes |
Cấu hình chân ADC0820CCN/PB
| Chân 1 | CS — Chip Select (active low) |
| Chân 2 | RD — Read strobe (active low) |
| Chân 3 | WR — Write/Convert start (active low) |
| Chân 4 | CLK — Clock input (or RC oscillator node) |
| Chân 5 | INTR — Interrupt / RDY output (active low) |
| Chân 6 | AIN — Analog input |
| Chân 7 | VREF — Voltage reference input |
| Chân 8 | GND — Ground (analog and digital common) |
| Chân 9 | D7 — Data bit 7 (MSB) |
| Chân 10 | D6 — Data bit 6 |
| Chân 11 | D5 — Data bit 5 |
| Chân 12 | D4 — Data bit 4 |
| Chân 13 | D3 — Data bit 3 |
| Chân 14 | D2 — Data bit 2 |
| Chân 15 | D1 — Data bit 1 |
| Chân 16 | D0 — Data bit 0 (LSB) |
| Chân 17 | OF — Offset adjust (optional external trim) |
| Chân 18 | MODE — Mode select (RD-only or WR-RD) |
| Chân 19 | NC — Not connected (per datasheet) |
| Chân 20 | V+ — Positive supply (5 V typical) |
Ứng dụng tiêu biểu
ADC0820CCN/PB phù hợp cho 6 Áp dụngs: Digital Voltmeter and Panel Meter, Process-Control Analog Front End, Video Signal Digitizing (Sub-Nyquist), Disk-Drive Servo Position Loops, Microprocessor-Based Data Logging, Automotive Sensor Conditioning (Sub-Systems).
Digital Voltmeter and Panel Meter
The ADC0820CCN/PB is well suited to digital panel meters and bench-top DVMs where 8-bit (1 part in 256 or 0.39 %) resolution is sufficient for general-purpose voltage readout on a 3.5-digit or 4-digit display. Placed between the input attenuator network and the host microcontroller, its 667 kSPS throughput over-samples mains-frequency noise to cancel it digitally while the internal track-and-hold captures the filtered DC level cleanly. Unlike a dedicated meter ASIC, the parallel output bus allows the same ADC to drive a custom LCD driver and host MCU simultaneously without an additional I/O expander.
Được đề xuất
Process-Control Analog Front End
In industrial process-control analog front-ends, the ADC0820CCN/PB digitizes 0-5 V signals from current-loop transducers, thermocouple amplifiers, or strain-gauge bridges at up to 667 kSPS, fast enough to close a single PID loop per millisecond on multiple channels when paired with an external analog mux. The internal track-and-hold settles the signal to the flash stage within 50 ns so the conversion is monotonic even if the input is slewing during conversion. Its 4.5 V to 8 V single-supply range matches 24 V-loop-derived 5 V rails used in PLC modules.
Được đề xuất
Video Signal Digitizing (Sub-Nyquist)
At 667 kSPS, the ADC0820CCN/PB samples composite video at sub-Nyquist rates for OEM video-frame-grabber cards, automotive reverse-camera modules, and CCTV preview channels where resolution beyond 8 bits adds cost without visible benefit. The semi-flash architecture delivers the throughput needed for two-channel 5 MHz single-channel conversion while the on-chip SHA prevents pixel-to-pixel sampling jitter. Designers typically pair it with an LMH6702 video op-amp front end to keep the 5 MHz signal chain flat.
Được đề xuất
Disk-Drive Servo Position Loops
The ADC0820CCN/PB handles the voice-coil position-error voltage in disk-drive servo loops, where its 2.5 us conversion time supports sample rates above 100 kSPS for stable multi-rate control. The 8-bit resolution is adequate to provide dither-free centering around the track-following setpoint, and the parallel read-out eliminates the latency of serial peripheral interfaces that would otherwise limit loop bandwidth. With its 5 V-only operation, the part integrates directly into legacy DSP-based servo boards without extra level translators.
Được đề xuất
Microprocessor-Based Data Logging
Legacy 8051 and Z80 data-acquisition boards use the ADC0820CCN/PB as the A/D front end because its 8-bit parallel bus maps onto the external memory space and its CS/WR/RD pins match the host's microcontrol-cycle buses. The two-step flash architecture performs a full conversion in roughly 1.5 bus cycles on a 12 MHz 80xx system, leaving enough bandwidth for time-multiplexing eight channels at a 10 Hz aggregate rate. This makes it a long-standing choice for environmental monitors and battery-powered instrumentation.
Được đề xuất
Automotive Sensor Conditioning (Sub-Systems)
While the ADC0820CCN/PB itself is rated 0 C to +70 C, several automotive auxiliary modules - climate-control panels, driver-info keypads, and chassis sensors in cabin zones - run within commercial-grade thermal limits and use it for fast 0-5 V sensor readout. Its 667 kSPS conversion speed is overkill for slow thermal readouts, so designers often multiplex eight sensors with a CD4051 to amortize the sampling rate. The integrated track-and-hold keeps transient spikes from sensors (e.g. inductive position sensors) from corrupting the conversion result.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho ADC0820CCN/PB — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | ADC0820CCN | ADC0820CCN/NOPB | ADC0820CC/D | ADC0820BCV | ADC0820CCN/B+ | LTC1099ACN#PBF |
|---|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | National Semiconductor (TI) | Analog Devices |
| Package | 20-pin PDIP | 20-pin PDIP (same) | 20-pin PDIP (same) | 20-pin PDIP (same) | 20-pin PDIP (same) | 20-pin PDIP (same) | 20-pin PDIP (same) |
| Resolution | 8 bit | 8 bit | 8 bit | 8 bit | 8 bit | 8 bit | 8 bit |
| Architecture | Semi-flash | Semi-flash | Semi-flash | Semi-flash | Semi-flash | Semi-flash | SAR / µP-compatible |
| Track-and-Hold | Yes (internal) | Yes (internal) | Yes (internal) | Yes (internal) | Yes (internal) | Yes (internal) | Yes (internal) |
| Output Interface | 8-bit parallel | 8-bit parallel | 8-bit parallel | 8-bit parallel | 8-bit parallel | 8-bit parallel | 8-bit parallel |
| RoHS Compliant | Yes (Pb-free) | Yes (older family) | Yes (NOPB) | Yes | Yes | Yes (Pb-free B+) | Yes (Pb-free #PBF) |
Bảo phân biệt quan trọng
- Longstanding TI / National Semiconductor legacy with mature tool support (vsLTC1099ACN#PBF)
- Standardized DROP-IN suffix progression for re-ordering (vsADC0820CCN (no Pb suffix))
- Internal track-and-hold eliminates an external SHA (vsBare SAR ADCs)
Ghi chú thiết kế
Place a 100 nF ceramic decoupling capacitor directly between V+ (pin 20) and GND (pin 8) as close to the leads as possible - ideally within 5 mm. For boards with several analog and digital loads, supplement this local cap with a single 10 uF tantalum or ceramic bulk capacitor within 50 mm to absorb supply transient currents drawn by the parallel output latches. Estimated: the ADC0820 draws under 30 mW at 5 V; the bulk cap only needs to sub-millisecond smoothing, so 10 uF is generous headroom.
Keep the analog input (pin 6, AIN) trace short and guarded on both sides with GND pours on a 2-layer board, or sandwiched between grounds on a 4-layer board. The reference input (pin 7, VREF) should be bypassed with a 10 uF + 100 nF RC network when fed by a precision reference (e.g. TL431ACDBZR); for ratiometric mode tie VREF directly to V+ through a low-impedance 0.1 inch trace. Avoid routing digital bus lines under the analog guard area or the precision reference footprint.
When the input signal swings into negative transients (e.g. AC coupled video or unbuffered sensors), a 100 ohm series resistor plus BAT54 Schottky clamp from AIN to GND prevents the input from exceeding the rated -0.1 V absolute minimum. Do not leave pin 17 (OF) floating; if the system does not require offset trim, tie OF to GND through a 10 kohm resistor or directly to GND. A floating OF pin can inject 1-2 LSB of drift in the transfer characteristic over temperature. The MODE pin (18) must be tied to either V+ or GND; leaving it open causes oscillating reads at startup.
Thông tin tuân thủ
RoHS compliant per TI product page and the PB terminal-finish code. Not AEC-Q100 qualified - the commercial 0C to +70C temperature grade is not suitable for automotive under-hood use; choose industrial-grade ADC0820CIN variants for -40C to +85C operation.
