Overview
The ADS7870EA/1K from Texas Instruments is a comprehensive low-power data acquisition system integrated into a single chip. It includes a 4-channel differential or 8-channel single-ended multiplexer, a precision programmable gain amplifier (PGA), a 12-bit successive approximation analog-to-digital (A/D) converter, and a precision voltage reference. This device is designed for low-power applications and offers high input impedance, excellent gain accuracy, good common-mode rejection, and low noise, making external amplification or impedance buffering unnecessary for many low-level signals.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Resolution | 12 Bits | |
| PGA Gains | 1, 2, 4, 5, 8, 10, 16, 20 V/V | |
| Input Channels | Up to 4 differential or up to 8 single-ended | |
| Internal Reference Voltages | 1.15 V, 2.048 V, 2.5 V | |
| Serial Interface | SPI/DSP Compatible, ≤20 MHz | |
| Throughput Rate | 52 kSamples/sec | |
| Supply Voltage | 2.7 V to 5.5 V | V |
| Operating Temperature Range | -40°C to 85°C | °C |
| Package | SSOP-28 |
Key Features
- Programmable gain amplifier with gains of 1, 2, 4, 5, 8, 10, 16, and 20 V/V.
- 12-bit successive approximation A/D converter with no missing codes.
- Internal voltage reference with options for 1.15 V, 2.048 V, or 2.5 V, trimmed for high initial accuracy and low temperature drift.
- SPI/DSP compatible serial interface supporting up to 20 MHz.
- Four general-purpose digital I/O pins accessible via the serial interface.
- Error overload indicator and programmable output format (2s complement or binary).
- Low power consumption with power-down mode available.
Applications
- Portable battery-powered systems.
- Low-power instrumentation.
- Low-power control systems.
- Smart sensor applications.
Q & A
- What is the resolution of the A/D converter in the ADS7870?
The A/D converter in the ADS7870 has a resolution of 12 bits.
- What are the available gains for the programmable gain amplifier (PGA)?
The PGA provides gains of 1, 2, 4, 5, 8, 10, 16, and 20 V/V.
- What are the options for the internal voltage reference?
The internal voltage reference can be configured for output voltages of 1.15 V, 2.048 V, or 2.5 V.
- What is the maximum throughput rate of the ADS7870?
The maximum throughput rate is 52 kSamples/sec.
- What is the operating temperature range for the ADS7870?
The operating temperature range is -40°C to 85°C.
- What type of package is the ADS7870 available in?
The ADS7870 is available in an SSOP-28 package.
- Does the ADS7870 support external clock inputs?
- How many digital I/O pins does the ADS7870 have?
The ADS7870 has four general-purpose digital I/O pins.
- What is the power consumption in power-down mode?
In power-down mode, the power consumption is approximately 5 µW.
- Is the ADS7870 compatible with various serial protocols?
