Overview
The MAX187/MAX189 are low-power, 12-bit serial analog-to-digital converters (ADCs) designed by Maxim Integrated, now part of Analog Devices Inc. These ADCs operate from a single +5V supply and accept analog input voltages ranging from 0 to 5V. They feature a successive-approximation ADC architecture, a fast track/hold circuit, an on-chip clock, and a high-speed 3-wire serial interface compatible with SPI, QSPI, and MICROWIRE protocols. The devices are known for their low power consumption and high accuracy, making them suitable for various applications requiring precise analog-to-digital conversion.
Key Specifications
| Parameter | Value | Notes |
|---|---|---|
| Resolution | 12 bits | |
| Supply Voltage | +5V ± 5% | |
| Analog Input Range | 0 to 5V | |
| Conversion Rate | 75 ksps | With external clock at 4 MHz |
| Conversion Time | 5.5 to 8.5 clock cycles | |
| Track/Hold Acquisition Time | 1.5 clock cycles | |
| Operating Current | 1.5 mA | |
| Shutdown Current | 2 µA | |
| Reference Voltage (MAX187) | 4.096V (internal), 2.5V to VDD (external) | |
| Operating Temperature Range | 0°C to +70°C (C grade), -40°C to +85°C (E grade) | |
| Package Types | 8-Pin PDIP, 16-Pin SO |
Key Features
- Low power consumption with 1.5 mA operating current and 2 µA shutdown current.
- Internal 4.096V buffered reference for the MAX187, and external reference option for both MAX187 and MAX189.
- High-speed 3-wire serial interface compatible with SPI, QSPI, and MICROWIRE protocols.
- Fast track/hold circuit with 1.5 clock cycles acquisition time.
- Small footprint in 8-Pin PDIP and 16-Pin SO packages.
- High accuracy with successive-approximation ADC architecture.
Applications
- Portable data logging systems.
- Remote digital signal processing.
- Isolated data acquisition systems.
- High-accuracy process control systems.
Q & A
- What is the resolution of the MAX187/MAX189 ADCs?
The MAX187/MAX189 ADCs have a resolution of 12 bits.
- What is the supply voltage range for the MAX187/MAX189?
The supply voltage range is +5V ± 5%.
- What is the analog input voltage range for these ADCs?
The analog input voltage range is from 0 to 5V.
- What is the conversion rate of the MAX187/MAX189 with an external clock?
The conversion rate is 75 ksps with an external clock at 4 MHz.
- How long does the conversion process take?
The conversion time is between 5.5 to 8.5 clock cycles.
- What is the track/hold acquisition time?
The track/hold acquisition time is 1.5 clock cycles.
- What are the operating and shutdown current values?
The operating current is 1.5 mA, and the shutdown current is 2 µA.
- What are the reference voltage options for the MAX187?
The MAX187 has an internal 4.096V buffered reference and supports an external reference from 2.5V to VDD.
- What are the available package types for the MAX187/MAX189?
The available package types are 8-Pin PDIP and 16-Pin SO.
- What are some typical applications for the MAX187/MAX189?
Typical applications include portable data logging, remote digital signal processing, isolated data acquisition, and high-accuracy process control.
