AD7828KPZ-REEL - 8-Bit 8-Channel 2.5µs ADC | Analog Devices
料号： AD7828KPZ-REEL ✗ 停产| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $12.5 | $12.50 |
| 10 | $11.2 | $112.00 |
| 100 | $9.8 | $980.00 |
| 500 | $8.75 | $4,375.00 |
| 1,000 | $7.95 | $7,950.00 |
AD7828KPZ-REEL 概述
An 8-bit ADC is a successive-approximation or flash-type data converter that quantizes an analog input voltage into 256 discrete digital codes with 8-bit resolution (≈39 mV per LSB on a 5 V full-scale input). Multichannel ADCs like the AD7828 integrate an input multiplexer, sample-and-hold, and reference buffer on-chip, allowing a single converter IC to monitor multiple sensors or process signals, reducing BOM cost and PCB area compared with one ADC per channel. In the broader signal-chain hierarchy, the ADC sits between the analog front end (sensor + amplifier + filter) and the digital domain (microcontroller, DSP, or FPGA), making its speed, channel count, and interface protocol the key selection criteria.
Key differentiating features of the AD7828 include the on-chip 8-input multiplexer with channel selection logic, built-in track-and-hold for 10 kHz full-scale signals, a fast microprocessor-compatible parallel interface, single 5 V operation, and the half-flash conversion architecture that delivers 2.5 µs conversion time without the die-area penalty of a full 8-bit flash design. The LC²MOS process ensures low power dissipation and high noise immunity for industrial and instrumentation front ends.
The half-flash (also called subranging or pipelined 2-step) architecture uses two 4-bit flash ADCs plus a DAC and subtractor to first resolve the 4 MSBs, then the 4 LSBs, halving the comparator count versus a full 8-bit flash converter. Combined with on-chip clock and reference circuitry, this yields a small die, low power, and 2.5 µs conversion without the latency of a SAR converter.
Typical applications include multiplexed data acquisition systems, industrial process control front ends, portable instrumentation, multichannel sensor monitoring, and any 8-bit embedded system that requires rapid sampling of multiple analog signals through a parallel bus. The wide 0°C to 70°C operating range makes it well suited to commercial and laboratory environments rather than full industrial (-40°C to +85°C) deployments.
When designing with the AD7828, route the analog inputs as short as possible and isolate them from digital return currents to preserve converter accuracy. Use the BYPASS pin with the recommended 10 µF/0.1 µF decoupling pair, hold RD high during startup to keep the output bus inactive, and verify that the parallel-mode timing matches your host microprocessor or DSP read-cycle specification.
直接替换替代料： AD7828KPZ-REEL ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： AD7828KPZ-REEL （相同外形与封装尺寸） ——差异在于 Architecture, Data Interface, Operating Temperature, Conversion Time, Package / Case.
快速对比工具——选择替代料号进行并排对比：
AD7828LPZ
✅ 直接替换📋 参考替代料（不在目录中）
AD7828KPZ
✅ 直接替换📋 参考替代料（不在目录中）
AD7828KPZ-REEL 最大额定值与电气特性
| Number of Bits | 8 |
| Sampling Rate (Per Second) | 50 k (2.5 µs/channel conversion) |
| Number of Inputs | 8 |
| Input Type | Single-Ended (Pseudo-Differential option via VIN1-) |
| Data Interface | Parallel |
| Architecture | Half-Flash (2-step subranging) |
| 封装 / 外壳 | 28-PLCC (J-Lead), 11.51 mm x 11.51 mm |
| 安装类型 | Surface Mount |
| 工作温度 | 0°C to +70°C |
| Supply Voltage (Single) | 5 V (±5%) |
| Power Dissipation (typ) | 40 mW |
| Input Signal Bandwidth | 10 kHz full-scale per channel (built-in T/H) |
| Reference | Internal (2.5 V); external reference option |
| Conversion Time | 2.5 µs (max) per channel |
| Process Technology | LC²MOS (Linear-Compatible CMOS) |
| Packaging (Reel) | Tape & Reel (TR) |
| RoHS 状态 | Compliant (lead-free PLCC) |
AD7828KPZ-REEL 引脚配置
| 引脚 1 | DB4 — Data output bit 4 |
| 引脚 2 | DB5 — Data output bit 5 |
| 引脚 3 | DB6 — Data output bit 6 |
| 引脚 4 | DB7 — Data output bit 7 (MSB) |
| 引脚 5 | AGND — Analog ground |
| 引脚 6 | REF IN/OUT — Reference input/output (2.5 V internal) |
| 引脚 7 | VIN1 — Analog input channel 1 |
| 引脚 8 | VIN2 — Analog input channel 2 |
| 引脚 9 | VIN3 — Analog input channel 3 |
| 引脚 10 | VIN4 — Analog input channel 4 |
| 引脚 11 | VIN5 — Analog input channel 5 |
| 引脚 12 | VIN6 — Analog input channel 6 |
| 引脚 13 | VIN7 — Analog input channel 7 |
| 引脚 14 | VIN8 — Analog input channel 8 |
| 引脚 15 | BYPASS — Bypass/decoupling pin (connect 10µF/0.1µF) |
| 引脚 16 | DGND — Digital ground |
| 引脚 17 | MODE — Mode select |
| 引脚 18 | CS — Chip select (active low) |
| 引脚 19 | RD — Read input (active low) |
| 引脚 20 | WR — Write input (active low) |
| 引脚 21 | A0 — Channel address bit 0 |
| 引脚 22 | A1 — Channel address bit 1 |
| 引脚 23 | A2 — Channel address bit 2 |
| 引脚 24 | DB0 — Data output bit 0 (LSB) |
| 引脚 25 | DB1 — Data output bit 1 |
| 引脚 26 | DB2 — Data output bit 2 |
| 引脚 27 | DB3 — Data output bit 3 |
| 引脚 28 | VCC — 5 V supply |
典型应用
AD7828KPZ-REEL 适用于 6 应用s: Multichannel Data Acquisition System, Industrial Process Control Front End, Portable Instrumentation & Test Equipment, Multichannel Sensor Monitoring (Temperature / Pressure / Strain), Embedded 8-bit Microcontroller Analog Expansion, Legacy Replacement & Maintenance.
Multichannel Data Acquisition System
The AD7828KPZ-REEL is well suited to multi-channel data-acquisition front ends where 8 single-ended analog inputs must be digitized through one ADC. The built-in 8-input analog multiplexer and on-chip track-and-hold eliminate external MUX and SHA ICs, reducing BOM cost. With 2.5 µs conversion time (50 ksps aggregate) and 10 kHz full-scale input bandwidth per channel, the AD7828 handles thermocouple, pressure-sensor, and strain-gauge multiplexing for SCADA-like systems. The parallel interface matches 8051-family and DSP host processors directly, supporting single-mode register read/write without glue logic.
推荐
Industrial Process Control Front End
In industrial process control, the AD7828KPZ-REEL digitizes sensor inputs from flow meters, pressure transmitters, and level sensors through its 8-channel MUX. The single 5 V supply and 40 mW dissipation simplify PLC and DCS analog-input module design, where dense channel-count boards must stay within thermal budgets. The half-flash architecture gives deterministic 2.5 µs conversion — important for synchronized control loops — and the parallel data bus allows direct connection to industrial microcontrollers. The 0°C to +70°C operating range suits factory-floor control cabinets.
推荐
Portable Instrumentation & Test Equipment
Portable bench instruments such as handheld multimeters, bench DMM data loggers, and oscilloscope auxiliary channels use the AD7828KPZ-REEL to digitize multiple analog signals through one converter. The 8-bit resolution is sufficient for display update, trend logging, and event-capture tasks; the 2.5 µs conversion allows sampling of audio-bandwidth signals. Low 40 mW power dissipation helps battery-powered designs, and the parallel interface simplifies connection to low-cost 8-bit microcontrollers such as the 8051 family. The 28-PLCC surface-mount package supports compact handheld enclosures.
推荐
Multichannel Sensor Monitoring (Temperature / Pressure / Strain)
The AD7828KPZ-REEL simplifies sensor aggregation by digitizing up to 8 conditioned sensor outputs through a single IC, ideal for HVAC control boards, refrigeration monitoring, and embedded sensor hubs. Each input sees a built-in track-and-hold capable of 10 kHz full-scale, allowing accurate digitization of multiplexed thermocouple, RTD-bridge, and load-cell signals after external amplification. The 8-bit resolution suits trend logging and threshold detection; for higher resolution the AD7327 12-bit SAR upgrade maintains channel count while improving precision. The parallel bus ties directly into microcontroller interrupt routines.
推荐
Embedded 8-bit Microcontroller Analog Expansion
Many 8-bit embedded designs based on 8051, HC11, or PIC microcontrollers need more analog channels than the integrated ADC provides — the AD7828KPZ-REEL acts as an external parallel ADC with 8 input channels. The parallel data bus and RD/CS/WR interface map directly onto standard 8051 MOVX instructions with no glue logic, and the 2.5 µs conversion allows polling of all 8 channels in 20 µs. Designers can keep the existing low-cost MCU while adding 8 channels of 8-bit analog input, simplifying firmware and reducing overall system cost.
推荐
Legacy Replacement & Maintenance
The AD7828KPZ-REEL is classified NRND (Not Recommended for New Designs) but remains shipped for legacy board repair, field-service replacement, and long-life industrial programs such as avionics retrofits, military-grade logistics, and medical device maintenance contracts. Stocking distributors such as DigiKey, Mouser, and Win-Source continue to inventory the tape-and-reel part for these legacy flows. Engineers designing new boards should migrate to the AD7828LPZ-REEL (same package, lower power) or modernize to the AD7327 12-bit SAR family.
推荐
推荐产品汇总
工程参考数据： AD7828KPZ-REEL ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | AD7828LPZ | AD7828KPZ | AD7828KP |
|---|---|---|---|---|
| Package | 28-PLCC (J-Lead) | 28-PLCC (J-Lead) - same | 28-PLCC (J-Lead) - same | 28-PDIP (through-hole, different footprint) |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Resolution | 8 bit | 8 bit | 8 bit | 8 bit |
| Number of Input Channels | 8 | 8 | 8 | 8 |
| Conversion Time | 2.5 µs | 2.5 µs | 2.5 µs | 2.5 µs |
| Power Dissipation (typ) | 40 mW | ~20 mW (lower-power variant) | 40 mW | 40 mW |
| Supply Voltage | 5 V | 5 V | 5 V | 5 V |
| Operating Temperature | 0°C to +70°C | 0°C to +70°C | 0°C to +70°C | 0°C to +70°C |
| Architecture | Half-Flash | Half-Flash | Half-Flash | Half-Flash |
| Packaging | Tape & Reel | Tube | Tube | Tube |
关键差异点
- Built-in 8-channel analog multiplexer （对比 AD7824 (4-channel variant))
- On-chip track-and-hold amplifier （对比 Discrete ADC + external SHA ICs)
- Single 5 V supply operation （对比 Earlier bipolar ADCs requiring ±12 V / ±15 V rails)
设计说明
Place a 10 µF tantalum or ceramic bypass capacitor on the BYPASS pin and a 0.1 µF ceramic decoupling capacitor as close as possible to the VCC pin. Route the analog inputs (VIN1-VIN8) as short as possible and isolate them from the digital data bus (DB0-DB7) and control lines (RD/WR/A0-A2/MODE) to prevent digital coupling into the analog MUX. Use a single ground plane split under the analog and digital pin groups with a star-ground at the AGND/DGND pins.
Do not apply input voltages outside the 0 V to VCC range on VIN1-VIN8 — exceeding VCC can damage the input MUX through the ESD diodes. Keep CS high during power-up so the parallel output bus remains in high-impedance and does not contend with other devices on the bus. The MODE pin must be set correctly for the chosen read timing (single-mode vs continuous-mode conversion); see the datasheet timing diagrams. The reference pin (REF IN/OUT) defaults to internal 2.5 V but can be driven externally if a system reference is preferred.
Source-impedance on each VINx should remain below 1 kΩ to avoid input-channel crosstalk and charge-sharing errors caused by the input MUX settling. Add a 100 pF to 1 nF buffer cap on each input if driving from higher-impedance sources. Maintain balanced PCB return paths between the analog and digital sections so the high-speed digital output transitions (DB0-DB7) do not couple into the analog ground reference. For high-density multilayer boards, route VCC through a wide trace or dedicated power plane to keep IR drop below 50 mV at the ADC supply pin.
合规信息
RoHS-compliant per Analog Devices product page (Z suffix indicates lead-free PLCC terminal finish). Not AEC-Q100 qualified — commercial-grade (0°C to +70°C) part only. REACH compliance per AD general statement; halogen-free status not explicitly stated for the AD7828 family and listed as unknown.
