Overview
The MX7821 is a high-speed, microprocessor-compatible (μP), 8-bit analog-to-digital converter (ADC) produced by Analog Devices Inc. It serves as a plug-in upgrade for the industry-standard 7820, offering enhanced performance and compatibility. The MX7821 utilizes a half-flash technique, resulting in a faster conversion time of 660ns compared to the 1.36μs of the 7820. This ADC is designed to digitize signals up to 100kHz and features a track-and-hold function, making it suitable for various high-speed applications.
Key Specifications
| Parameter | Value |
|---|---|
| Resolution | 8 bits |
| Conversion Time | 660 ns |
| Analog Input Range | Bipolar (with VSS pin) |
| Signal Bandwidth | Up to 100 kHz |
| Power Supply | Dual power supplies supported |
| Interface | Microprocessor-compatible, appears as a memory location or I/O port |
| Data Outputs | Latched, three-state buffered circuitry |
| Package Options | Plastic Dual-In-Line, Narrow (0.3in), Small-Outline IC, Wide (0.3in) |
Key Features
- High-speed conversion using half-flash technique
- Track-and-hold function capable of digitizing up to 100kHz signals
- Microprocessor-compatible interface, no external logic required
- Latched, three-state buffered data outputs for direct connection to μP data bus or system input port
- Overflow output for cascading devices to achieve higher resolution
- Ratiometric operation supported through input/reference arrangement
- Dual power supplies supported with VSS pin
Applications
- High-speed data acquisition systems
- Industrial control systems
- Automated test equipment
- Medical devices requiring fast analog-to-digital conversion
- Avionics and aerospace applications
Q & A
- What is the conversion time of the MX7821 ADC?
The conversion time of the MX7821 ADC is 660 ns. - What is the resolution of the MX7821 ADC?
The resolution of the MX7821 ADC is 8 bits. - Can the MX7821 ADC handle bipolar analog inputs?
Yes, the MX7821 ADC can handle bipolar analog inputs with the support of the VSS pin. - What is the maximum signal bandwidth that the MX7821 can digitize?
The MX7821 can digitize signals up to 100 kHz. - Does the MX7821 require external interface logic for microprocessor connection?
No, the MX7821 does not require external interface logic as it appears as a memory location or I/O port. - What type of data output circuitry does the MX7821 use?
The MX7821 uses latched, three-state buffered circuitry for its data outputs. - Can the MX7821 be cascaded for higher resolution?
Yes, the MX7821 has an overflow output that allows cascading devices to achieve higher resolution. - What are the package options available for the MX7821?
The MX7821 is available in Plastic Dual-In-Line, Narrow (0.3in), and Small-Outline IC, Wide (0.3in) packages. - Is the MX7821 compatible with the industry-standard 7820?
Yes, the MX7821 is designed as a plug-in upgrade for the industry-standard 7820. - What is the purpose of the VSS pin in the MX7821?
The VSS pin supports dual power supplies and bipolar analog inputs.
