19-4302; Rev 3; 7/10
KIT
ATION
EVALU
ABLE
AVAIL
24-Bit, 4-Channel, Simultaneous-Sampling,
Cascadable, Sigma-Delta ADC
The MAX11040 is a 24-bit, 4-channel, simultaneoussampling, sigma-delta analog-to-digital converter
(ADC). The device allows simultaneous sampling of as
many as 32 channels using a built-in cascade feature
to synchronize as many as eight devices. The serial
interface of the MAX11040 allows reading data from all
the cascaded devices using a single command. Four
modulators simultaneously convert each fully differential analog input with a programmable data output rate
ranging from 0.25ksps to 64ksps. The device achieves
106dB SNR at 16ksps and 117dB SNR at 1ksps. The
MAX11040 operates from a single +3V supply. The differential analog input range is ±2.2V when using the
internal reference, an external reference is optional.
Each input is overvoltage protected up to ±6V without
damage. The device uses an internal crystal oscillator
or an external source for clock.
The MAX11040 is compatible with SPI™, QSPI™,
MICROWIRE™, and DSP-compatible 4-wire serial interfaces. An on-board interface logic allows one serial interface (with a single chip select) to control up to eight
cascaded devices or 32 simultaneous sampling analog
input channels.
The MAX11040 is ideally suited for power-management
systems. Each channel includes an adjustable sampling phase enabling internal compensation for phase
shift due to external dividers, transformers, or filters at
the inputs. The output data rate is adjustable with a
0.065% resolution (at 16ksps or below) to track the
varying frequency of a periodic input. A SYNC input
allows periodic alignment of the conversion timing of
multiple devices with a remote timing source.
The MAX11040 is available in a 38-pin TSSOP package
specified over the -40°C to +105°C industrial temperature range.
Applications
Power Protection Relay Equipment
Multiphase Power Systems
Industrial Data-Acquisition Systems
Medical Instrumentation
Features
o Four Fully Differential Simultaneously Sampled
Channels
o Cascadable for Up to 32 Channels of
Simultaneous Sampling
o 106dB SNR at 16ksps
o 117dB SNR at 1ksps
o 0.25% Error Over a 1000:1 Dynamic Range,
Processed Over 16.7ms
o ±2.2V Full-Scale Input Range
o ±6V Overvoltage Protected Inputs
o Internal Crystal Oscillator
o 2.5V, 50ppm/°C Internal Reference or External
Reference
o Programmable Output Data Rate
0.25ksps to 64ksps Range
0.065% Resolution
o Programmable Sampling Phase
0 to 333µs Delay in 1.33µs Steps
o SPI-/QSPI-/MICROWIRE-/DSP-Compatible 4-Wire
Serial Interface
o Cascadable Interface Allows Control of Up to
Eight Devices with a Single CS Signal
o 3.0V to 3.6V Analog Supply Voltage
o 2.7V to VAVDD Digital Supply Voltage
o 38-Pin TSSOP Package
Functional Diagram
OVRFLW
AIN0+
24-BIT
ADC
AIN0-
FAULT
SYNC
DIGITAL
FILTER
DRDYIN
REF0
AIN1+
24-BIT
ADC
AIN2-
DIGITAL
FILTER
24-BIT
ADC
REF1
AIN2+
DRDYOUT
DIGITAL
FILTER
24-BIT
ADC
AIN1-
DIGITAL
FILTER
REGISTERS AND
DIGITAL
CONTROL
SERIAL
INTERFACE
CASCIN
CASCOUT
CS
SCLK
REF2
AIN3+
AIN3-
DIN
DOUT
REF3
Ordering Information
MAX11040
PART
TEMP RANGE
PIN-PACKAGE
MAX11040GUU+
-40°C to +105°C
38 TSSOP
+Denotes a lead(Pb)-free/RoHS-compliant package.
MICROWIRE is a trademark of National Semiconductor Corp.
SPI/QSPI are trademarks of Motorola Inc.
2.5V
REFERENCE
REFIO
AGND
CRYSTAL
OSCILLATOR
XIN
XOUT
CLKOUT
DGND
Pin Configuration appears at end of data sheet.
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
1
MAX11040
General Description
