Maxim > Products > Analog-to-Digital Converters > MX7705

MX7705

16-Bit, Low-Power, 2-Channel, Sigma-Delta ADC

Overview

Technical Documents

Ordering Info

Status

Active: In Production.

Description

The MX7705 low-power, 2-channel, serial-output analog-to-digital converter (ADC) includes a sigma-delta modulator with a digital filter to achieve 16-bit resolution with no missing codes. This ADC is pin compatible and software compatible with the AD7705. The MX7705 features an on-chip input buffer and programmable-gain amplifier (PGA). The device offers an SPI™-/QSPI™-/MICROWIRE™-compatible serial interface.

The MX7705 operates from a single 2.7V to 5.25V supply. The operating supply current is 320µA (typ) with a 3V supply. Power-down mode reduces the supply current to 2µA (typ).

Self-calibration and system calibration allow the MX7705 to correct for gain and offset errors. Excellent DC performance (±0.003% FSR INL) and low noise (650nV) make the MX7705 ideal for measuring low-frequency signals with a wide dynamic range. The device accepts fully differential bipolar/unipolar inputs. An internal input buffer allows for input signals with high source impedances. An on-chip digital filter, with a programmable cutoff and output data rate, processes the output of the sigma-delta modulator. The first notch frequency of the digital filter is chosen to provide 150dB rejection of common-mode 50Hz or 60Hz noise and 98dB rejection of normal-mode 50Hz or 60Hz noise. A PGA and digital filtering allow signals to be directly acquired with little or no signal-conditioning requirements.

The MX7705 is available in a 16-pin TSSOP package.

Data Sheet

Download	Rev 4	(PDF, 528kB)
E-Mail

Key Features

Pin Compatible and Software Compatible with the AD7705
16-Bit Sigma-Delta ADC
Two Fully Differential Input Channels
0.003% Integral Nonlinearity with No Missing Codes
Interface with Schmitt Triggers on Inputs
Internal Analog Input Buffers
PGA from 1 to 128
Single (2.7V to 3.6V) or (4.75V to 5.25V) Supply
Low Power
- 1mW (max), 3V Supply
- 2µA (typ) Power-Down Current
SPI-/QSPI-/MICROWIRE-Compatible 3-Wire Serial Interface

Applications/Uses

Flow and Gas Meters
Industrial Instruments
Loop-Powered Systems
Medical Instrumentation
Pressure Transducers
RTD Measurements
Strain-Gauge Measurements
Thermocouple Measurements
Weigh Scales

Key Specifications:

Precision ADCs (< 5Msps)

Part Number

Resolution
(bits)

Input Chan.

Conv. Rate
(ksps)

Data Bus
(bits)

Diff/S.E. Input

External V_REF
(V)

Unipolar V_IN
(V)

Bipolar V_IN
(±V)

INL
(±LSB)

Package/Pins

Budgetary Price

ADC

max

min

max

See Notes

MX7705

0.5

SPI

Diff. Only

3.5

2.5

1.96608

See All Precision ADCs (< 5Msps) (417)

Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

Diagram

Functional Diagram

Application Notes

Application Note 3418		Understanding the Effects of Clock Tolerances on 50/60Hz Noise Rejection in High Performance Sigma Delta ADCs
Application Note 4026		Implementing Cold-Junction Compensation in Thermocouple Applications
Tutorial 4699		Overview of Sensor Signal Paths
Reference Design 5032		Modern Thermocouples and a High-Resolution Delta-Sigma ADC Enable High-Precision Temperature Measurement

Product Guides

Signal Chain (PDF)

Reliability Reports

Show FIT data for:
Request Reliability Report for:

Software/Models

none

Ordering Information

Filters:

Part Number:

Package:

Temperature:

Tape and Reel

Sample

Part Number	Free Sample	Buy	Status	Package: TYPE PINS FOOTPRINT DRAWING CODE/VAR *	Temp	RoHS/Lead-Free? Materials Analysis
MX7705EPE			Active	PDIP(N);16 pin;158.4 mm² Outline Drawing:21-0043 (PDF) Land Pattern: Not Applicable Use pkgcode/variation: P16-1*	-40°C to +85°C	RoHS/Lead-Free: No Materials Analysis
MX7705EPE+			Active	PDIP(N);16 pin;158.4 mm² Outline Drawing:21-0043 (PDF) Land Pattern: Not Applicable Use pkgcode/variation: P16+1*	-40°C to +85°C	RoHS/Lead-Free: Lead Free Materials Analysis
MX7705EUE			Active	TSSOP;16 pin;33.4 mm² Outline Drawing:21-0066 (PDF) Land Pattern: 90-0117 (PDF) Use pkgcode/variation: U16-2*	-40°C to +85°C	RoHS/Lead-Free: No Materials Analysis
MX7705EUE+			Active	TSSOP;16 pin;33.4 mm² Outline Drawing:21-0066 (PDF) Land Pattern: 90-0117 (PDF) Use pkgcode/variation: U16+2*	-40°C to +85°C	RoHS/Lead-Free: Lead Free Materials Analysis
MX7705EUE+T			Active	TSSOP;16 pin;33.4 mm² Outline Drawing:21-0066 (PDF) Land Pattern: 90-0117 (PDF) Use pkgcode/variation: U16+2*	-40°C to +85°C	RoHS/Lead-Free: Lead Free Materials Analysis
MX7705EUE-T			Active	TSSOP;16 pin Land Pattern: Not Available	-40°C to +85°C	See data sheet
MX7705EWE			Active	SOIC(W);16 pin;111.8 mm² Outline Drawing:21-0042 (PDF) Land Pattern: 90-0107 (PDF) Use pkgcode/variation: W16-1*	-40°C to +85°C	RoHS/Lead-Free: No Materials Analysis
MX7705EWE+			Active	SOIC(W);16 pin;111.8 mm² Outline Drawing:21-0042 (PDF) Land Pattern: 90-0107 (PDF) Use pkgcode/variation: W16+1*	-40°C to +85°C	RoHS/Lead-Free: Lead Free Materials Analysis
MX7705EWE+T			Active	SOIC(W);16 pin;111.8 mm² Outline Drawing:21-0042 (PDF) Land Pattern: 90-0107 (PDF) Use pkgcode/variation: W16+1*	-40°C to +85°C	RoHS/Lead-Free: Lead Free Materials Analysis
MX7705EWE-T			Active	W.SO;16 pin Land Pattern: Not Available	-40°C to +85°C	See data sheet

Notes:

Other options and links for purchasing parts are listed at: http://www.maxim-ic.com/sales.
Didn't Find What You Need? Ask our applications engineers. Expert assistance in finding parts, usually within one business day.
Part number suffixes: T or T&R = tape and reel; + = RoHS/lead-free; # = RoHS/lead-exempt; -D = drypack; -U/+U on DS parts = cut tape. More: See Full Data Sheet or Maxim Product Naming Conventions.
* Some packages have variations, listed on the drawing. "PkgCode/Variation" tells which variation the product uses. Note that "+", "#", "-" in the part number suffix describes RoHS status. Package drawings may show a different suffix character.

Similar Products by Function

MAX1415, MAX1416	16-Bit, Low-Power, 2-Channel, Sigma-Delta ADCs
See All Precision ADCs (< 5Msps) (424 Products)

More Information

New Product Press Release

[ 2003-11-21 ]

Didn't Find What You Need?

Next Day Product Selection Assistance from Applications Engineers
Parametric Search
Applications Help

Information Index

Overview		Technical Documents		Ordering Info		Related Products
Description Key Features Applications/Uses Key Specifications Diagram Notes and Comments		Data Sheet Application Notes Evaluation Kits Product Guides Reliability Reports Software/Models		Price and Availability Samples Buy Online Package Information Lead-Free Information		Similar Products by Function Similar Products by Application Evaluation Kits Products with Similar Part Numbers Products Used With This

Document Ref.: 19-3051 Rev 4; 2010-05-04
This page last modified: 2010-05-04