MAX199AENI - 12-Bit 8-Ch DAS, +5V, Multi-Range ADC | Maxim
料号： MAX199AENI ✗ 停产| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $18.5 | $18.50 |
| 10 | $17.2 | $172.00 |
| 100 | $14.95 | $1,495.00 |
| 500 | $12.8 | $6,400.00 |
| 1,000 | $10.45 | $10,450.00 |
MAX199AENI 概述
A Data Acquisition System (DAS) is an integrated mixed-signal IC that combines an analog input multiplexer, sample-and-hold amplifier, analog-to-digital converter (ADC), voltage reference, and digital interface into a single package. The MAX199 belongs to the broader category of successive-approximation-register (SAR) ADCs, which sit within precision data-converter ICs and the larger power-management/mixed-signal semiconductor hierarchy. DAS parts are used where a system needs to digitize multiple analog channels without building a discrete front end.
Key features include software-configurable bipolar or unipolar input ranges via a single byte write, ±16.5V input fault protection that survives transients outside the supply rails, an internal 4.096V precision reference with ±0.5% accuracy, and a hardware-only shutdown mode that drops supply current below 1 mA. The internal MUX settles within 1.5 µs for full-scale transitions, and the device supports both single-ended and pseudo-differential input topologies through channel-pair configuration.
Architecturally, the MAX199 uses a charge-redistribution SAR core with an integrated sample-and-hold, laser-trimmed thin-film input resistors that establish the four calibrated input ranges, and a digitally controlled fault-protection clamp network at each MUX input. Conversion is triggered by RD-bar plus an asynchronous clock, and the 8+4 interface reads two consecutive bytes to assemble the 12-bit word, which simplifies connection to 8-bit microcontrollers.
Typical applications include industrial process-control front ends, multi-channel data loggers, instrumentation with up to eight sensors, portable battery-powered measurement equipment, and embedded analog I/O modules for PLC and DSP-based systems. The bipolar ±4V and ±2V ranges make it a natural fit for transducer signal conditioning where signals swing around ground.
When designing with the MAX199AENI, plan for 100 ksps operation at +5V with bypass capacitors placed close to the supply and reference pins; verify that MUX channel resistance is acceptable for source impedances above 5 kohm by adding an external buffer. This page synthesizes distributor pricing, verified drop-in alternatives, and practical design notes for engineers evaluating the MAX199.
直接替换替代料： MAX199AENI ——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： MAX199AENI （相同外形与封装尺寸） ——差异在于 Mounting Type, Operating Temperature, Package, Supply Voltage.
快速对比工具——选择替代料号进行并排对比：
MAX199AENI+
✅ 直接替换📋 参考替代料（不在目录中）
MAX199BENI
✅ 直接替换📋 参考替代料（不在目录中）
MAX199BENI+
✅ 直接替换📋 参考替代料（不在目录中）
MAX199ACNI+
✅ 直接替换📋 参考替代料（不在目录中）
MAX199AENI 最大额定值与电气特性
| Manufacturer | Analog Devices / Maxim Integrated |
| Part Number | MAX199AENI |
| Description | 8-Channel, Multi-Range, 5V, 12-Bit DAS with 8+4 Bus Interface and Fault Protection |
| 功能 | Data Acquisition System (DAS) - multi-channel ADC |
| 分辨率 | 12 bit |
| Number of Input Channels | 8 |
| 采样率 | 100 ksps |
| Input Voltage Ranges | ±4V, ±2V, +4V, +2V (software-selectable) |
| Input Fault Protection | ±16.5V (with power off) |
| 电源电压 | +5V single supply |
| 接口类型 | Parallel 8+4 bus |
| Reference | Internal 4.096V (typ) |
| 封装 | 28-pin PDIP (DIP-28) |
| 工作温度 | -40C to +85C (industrial) |
| 安装类型 | Through-hole (PDIP) |
| RoHS 状态 | Compliant |
| Lifecycle | Obsolete (last-time-buy recommended) |
MAX199AENI 引脚配置
| 引脚 1 | AIN0 — Analog input channel 0 |
| 引脚 2 | AIN1 — Analog input channel 1 |
| 引脚 3 | AIN2 — Analog input channel 2 |
| 引脚 4 | AIN3 — Analog input channel 3 |
| 引脚 5 | AIN4 — Analog input channel 4 |
| 引脚 6 | AIN5 — Analog input channel 5 |
| 引脚 7 | AIN6 — Analog input channel 6 |
| 引脚 8 | AIN7 — Analog input channel 7 |
| 引脚 9 | AGND — Analog ground |
| 引脚 10 | REF — Internal 4.096V reference output |
| 引脚 11 | REFADJ — Reference adjust input |
| 引脚 12 | VDD — +5V analog supply |
| 引脚 13 | D7 — Data bit 7 (MSB of high byte) |
| 引脚 14 | D6 — Data bit 6 |
| 引脚 15 | D5 — Data bit 5 |
| 引脚 16 | D4 — Data bit 4 |
| 引脚 17 | D3 — Data bit 3 (LSB of high byte) / high byte enable |
| 引脚 18 | D2/D11 — Data bit 2 (low byte high nibble) |
| 引脚 19 | D1/D10 — Data bit 1 |
| 引脚 20 | D0/D9 — Data bit 0 (LSB of low byte) |
| 引脚 21 | DGND — Digital ground |
| 引脚 22 | CLK — External conversion clock input (or float for internal) |
| 引脚 23 | INT-bar — Conversion complete interrupt (active low) |
| 引脚 24 | MODE — Mode select input |
| 引脚 25 | WR-bar — Write input for control register (active low) |
| 引脚 26 | RD-bar — Read input - initiates conversion (active low) |
| 引脚 27 | CS-bar — Chip select (active low) |
| 引脚 28 | HBEN — High byte enable for 8+4 interface |
典型应用
MAX199AENI 适用于 6 应用s: Industrial Process Control Front End, Multichannel Data Logger, Instrumentation and Test Equipment, Portable Battery-Powered Measurement, Embedded Analog I/O for DSP Systems, Sensor Array Interface Board.
Industrial Process Control Front End
The MAX199AENI suits multi-channel industrial PLC front ends where 8 analog inputs must be digitized from a single +5V rail. Its software-selectable ±4V, ±2V, +4V, +2V input ranges accept both bipolar transducer outputs (strain gauges, load cells) and unipolar 4-20 mA derived signals through a shunt. With 100 ksps throughput across the 8-channel MUX, the part can scan eight sensors at 12 ksps each, well above typical 100 Hz industrial control loops. The ±16.5V input fault protection survives wiring faults and ESD on field cabling, while the internal 4.096V reference eliminates an external precision reference. Place the IC adjacent to the analog input connector with ground plane stitching, and pair with an op-amp buffer per channel for source impedances above 5 kohm to maintain 12-bit accuracy.
推荐
Multichannel Data Logger
Battery-powered and line-powered data loggers benefit from the MAX199AENI's single +5V supply, 8-channel MUX, and shutdown-mode current below 1 mA. The 100 ksps maximum sample rate lets the device log slow-varying signals (environmental sensors, thermocouples amplified to the ±4V or +4V range) at hundreds of Hz per channel without aliasing. Internal track/hold and the precision 4.096V reference remove external analog components, reducing BOM cost and board area. For systems requiring higher channel counts, two MAX199AENI parts can be paralleled with separate CS-bar chip selects and synchronized by an external clock, expanding the MUX to 16 channels with shared reference accuracy.
推荐
Instrumentation and Test Equipment
Bench-top and rack-mount instruments that digitize multiple analog sources (DMM front ends, signal analyzer input stages, ATE pin cards) use the MAX199AENI to combine an 8-channel MUX, sample-and-hold, ADC, and reference in a single 28-pin PDIP. The 8+4 parallel bus interface is a natural fit for legacy 8-bit microcontroller-based instrument designs (8051, 68HC11) without external logic. With ±16.5V fault protection, the part tolerates accidental overvoltage on test inputs and continues operating without latch-up. Use the MAX199AENI's four software-selectable ranges to span signals from millivolt-level sensors to ±4V industrial outputs, eliminating mechanical range-switch relays.
推荐
Portable Battery-Powered Measurement
The MAX199AENI operates from +5V with low supply current, fitting portable measurement instruments powered by USB, 4xAA, or wall adapters. Its hardware-only shutdown mode reduces supply current to less than 1 mA when not converting, extending battery life between scans. The 28-pin PDIP package is through-hole, simplifying prototype and lab work, and the internal 4.096V reference eliminates the need for a separate precision reference IC, reducing cost and quiescent drain. For handheld multimeter or field data-acquisition designs, the part supports bipolar ranges that directly accept AC-coupled transducer signals without conditioning circuits.
推荐
Embedded Analog I/O for DSP Systems
DSP-based control systems (audio processors, motor control, vibration analysis) use the MAX199AENI to digitize analog feedback from multiple sensors (current shunts, accelerometers, position sensors). The 100 ksps sample rate supports DSP control loops with 10 kHz bandwidth across up to 8 channels simultaneously. The parallel 8+4 bus connects directly to DSP external memory interfaces (TMS320, ADSP-21xx) without glue logic, and the asynchronous conversion start lets the DSP precisely timestamp acquisitions. Pair the MAX199AENI with a companion Maxim DAC (MAX5742, MAX541) to build a complete analog I/O node for closed-loop DSP control. Internal track/hold settles in 1.5 µs, suitable for step changes in feedback signals during transients.
推荐
Sensor Array Interface Board
Sensor-array boards (8-channel thermocouple amplifiers, RTD arrays, photodiode multiplexers) interface to microcontrollers through the MAX199AENI's 8-channel MUX and 12-bit ADC. The software-configurable input ranges let one hardware design accept 0-4V photodiode amplifiers and ±4V strain-gauge bridges simply by writing a control byte, eliminating range-switch hardware. With 100 ksps conversion throughput, the array can be scanned at 12.5 ksps per channel, sufficient for vibration and thermal-shock monitoring. The ±16.5V input fault protection survives mis-wired sensor cables during field installation. Pair with a 5V low-dropout regulator and a digital isolator to build a complete isolated sensor-interface board.
推荐
推荐产品汇总
工程参考数据： MAX199AENI ——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 | MAX199AENI+ | MAX199BENI | MAX199BENI+ | MAX199ACNI+ |
|---|---|---|---|---|---|
| Package | 28-pin PDIP | 28-pin PDIP - same | 28-pin PDIP - same | 28-pin PDIP - same | 28-pin PDIP - same |
| Brand | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated |
| Resolution | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit |
| Channels | 8 | 8 | 8 | 8 | 8 |
| Sampling Rate | 100 ksps | 100 ksps | 100 ksps | 100 ksps | 100 ksps |
| Input Ranges | ±4V, ±2V, +4V, +2V | ±4V, ±2V, +4V, +2V | ±4V, ±2V, +4V, +2V | ±4V, ±2V, +4V, +2V | ±4V, ±2V, +4V, +2V |
| Fault Protection | ±16.5V | ±16.5V | ±16.5V | ±16.5V | ±16.5V |
| Supply Voltage | +5V | +5V | +5V | +5V | +5V |
| RoHS Compliant | No (standard version) | Yes | No (standard version) | Yes | Yes |
关键差异点
- Software-configurable input ranges eliminate external resistor dividers （对比 MAX197AENI)
- Higher linearity B-grade option for precision instrumentation （对比 MAX199BENI)
- RoHS-compliant variant available for Pb-free designs （对比 MAX199AENI+)
设计说明
Decouple VDD (pin 12) with a 1 µF tantalum and a 0.1 µF ceramic capacitor placed within 5 mm of the supply pin. The MAX199AENI's internal reference (pin 10, 4.096V) should be bypassed with a 4.7 µF low-ESR capacitor (tantalum or ceramic) to REFADJ (pin 11) and AGND (pin 9). The reference can deliver up to 1 mA; do not use it as a system reference if more current is needed. In shutdown mode (CS-bar and RD-bar high), supply current drops below 1 mA. Keep analog and digital grounds separate and join them at a single point near the AGND pin to minimize digital noise coupling into the MUX.
Lay out the analog inputs with short, parallel traces to maintain common-mode rejection. Keep analog input traces away from the parallel digital bus (D7-D0, CS-bar, RD-bar, WR-bar) and the clock signal (pin 22) by at least 5 mm or with a ground guard trace. Place the chip with its analog pins facing the analog input connector and digital pins facing the microcontroller, splitting AGND (pin 9) and DGND (pin 21) ground planes under the IC and joining them at the AGND pin. The internal MUX has approximately 1.5 kohm of on-resistance; source impedances above 5 kohm degrade the acquisition settling and should be buffered externally.
Do not exceed ±16.5V on any analog input pin, even with the supply removed - the input protection network uses diode clamps to VDD and AGND, but sustained over-voltage may damage the device. The 8+4 bus interface requires two consecutive reads: first read with HBEN (pin 28) high to get D11-D8, then HBEN low for D7-D0. Forget to toggle HBEN and you will only get 4-bit conversions. Channel switching requires a 1.5 µs acquisition settling time before initiating conversion; reading immediately after a MUX change can return wrong data. The MODE pin (24) selects interface timing mode and must be tied high or low per datasheet.
合规信息
Standard MAX199AENI is non-RoHS (SnPb finish); the MAX199AENI+ is the RoHS-compliant Pb-free variant. AEC-Q100 not applicable (industrial/commercial ADC, not automotive qualified).
