AD7707BRUZ Product Details
FEATURES
Charge balancing ADC
16 bits, no missing codes
±0.003% nonlinearity
High level (±10 V) and low level (±10 mV) input channels
True bipolar ±100 mV capability on low level input
Channels without requiring charge pumps
Programmable gain front end
Gains from 1 to 128
3-wire serial interface
SPI, QSPI™, MICROWIRE™ and DSP compatible
Schmitt trigger input on SCLK
Ability to buffer the analog input
2.7 V to 3.3 V or 4.75 V to 5.25 V operation
Power dissipation 1 mW at 3 V
Standby current 8 μA maximum
20-lead SOIC and TSSOP packages
GENERAL DESCRIPTION
The AD7707BRUZ is a complete analog front end for low frequency measurement applications. This 3-channel device can accept either low level input signals directly from a transducer or high level (±10 V) signals and produce a serial digital output. It employs a Σ-Δ conversion technique to realize up to 16 bits of no missing codes performance. The selected input signal is applied to a proprietary programmable gain front end based around an analog modulator. The modulator output is processed by an on-chip digital filter. The first notch of this digital filter can be programmed via an on-chip control register allowing adjustment of the filter cutoff and output update rate.
The AD7707BRUZ operates from a single 2.7 V to 3.3 V or 4.75 V to 5.25 V supply. The AD7707BRUZ features two low level pseudo differential analog input channels, one high level input channel and a differential reference input. Input signal ranges of 0 mV to 20 mV through 0 V to 2.5 V can be accommodated on both low level input channels when operating with a VDD of 5 V and a reference of 2.5 V. They can also handle bipolar input signal ranges of ±20 mV through ±2.5 V, which are referenced to the LCOM input. The AD7707, with a 3 V supply and a 1.225 V reference, can handle unipolar input signal ranges of 0 mV to 10 mV through 0 V to 1.225 V. Its bipolar input signal ranges are ±10 mV through ±1.225 V. The high level input channel can accept input signal ranges of ±10 V, ±5 V, 0 V to 10 V and 0 V to 5 V. The AD7707BRUZ thus performs all signal conditioning and conversion for a 3-channel system.
The AD7707BRUZ is ideal for use in smart, microcontroller or DSPbased systems. It features a serial interface that can be configured for 3-wire operation. Gain settings, signal polarity and update rate selection can be configured in software using the input serial port. The part contains self-calibration and system calibration options to eliminate gain and offset errors on the part itself or in the system.
CMOS construction ensures very low power dissipation, and the power-down mode reduces the standby power consumption to 20 μW typical. This part is available in a 20-lead wide body (0.3 inch) small outline (SOIC) package and a low profile 20-lead TSSOP
Feature
- Charge balancing ADC16 bits no missing codes0.003% nonlinearity
- High level (±10 V) and low level (±10 mV) input channels
- True bipolar ±100 mV capability on low level inputChannels without requiring charge pumps
- Programmable gain front end
- Gains from 1 to 128
- 3-wire serial interfaceSPI®, QSPI™, MICROWIRE™ and DSP CompatibleSchmitt trigger input on SCLK
- Ability to buffer the analog input
- 2.7 V to 3.3 V or 4.75 V to 5.25 V operation
- Power dissipation 1 mW @ 3 V
- Standby current 8 µA max
- 20-Lead SOIC and TSSOP Packages
(Picture: Pinout)
(Picture: Diagram)
