MAXIM MAX1416EUE

19-3163; Rev 1; 12/05
KIT
ATION
EVALU
E
L
B
AVAILA
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
Features
The MAX1415/MAX1416 low-power, 2-channel, serialoutput analog-to-digital converters (ADCs) use a sigmadelta modulator with a digital filter to achieve 16-bit
resolution with no missing codes. These ADCs are pincompatible upgrades to the MX7705/AD7705. The
MAX1415/MAX1416 feature an internal oscillator (1MHz
or 2.4576MHz), an on-chip input buffer, and a programmable gain amplifier (PGA). The devices offer an SPI™-/
QSPI™-/MICROWIRE™-compatible serial interface.
The MAX1415 requires a single 2.7V to 3.6V supply, and
the MAX1416 requires a single 4.75V to 5.25V supply.
The operating supply current is 400µA (max) with a 3V
supply. Power-down mode reduces the supply current to
2µA (typ). When operating with a supply of 3V, the power
dissipation is less than 1.44mW, making the MAX1415
ideal for battery-powered applications.
Self-calibration and system calibration allow the
MAX1415/MAX1416 to correct for gain and offset errors.
Excellent DC performance (±0.0015% FSR INL) and low
noise (700nV in unbuffered mode) make the MAX1415/
MAX1416 ideal for measuring low-frequency signals with
a wide dynamic range. These devices accept 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 MAX1415/MAX1416 are available in 16-pin PDIP,
SO, and TSSOP packages.
♦ 16-Bit Sigma-Delta ADCs
♦ Two Fully Differential Input Channels
♦ 0.0015% Integral Nonlinearity with No Missing
Codes
♦ Internal Analog Input Buffers
♦ Programmable Gain Amplifier (PGA) from 1 to 128
♦ Internal Oscillator (2.4576MHz or 1MHz)
Applications
Industrial Instruments
♦ Single 2.7V to 3.6V (MAX1415) or 4.75V to 5.25V
(MAX1416) Supply
♦ Low Power
1mW max, 3V Supply
2µA (typ) Power-Down Current
♦ SPI™-/QSPI™-/MICROWIRE™-Compatible 3-Wire
Serial Interface
♦ Pin Compatible with MX7705/AD7705
♦ 16-Pin PDIP, SO, and TSSOP Packages
Ordering Information
TEMP
RANGE
PART
PINPACKAGE
VDD
(V)
PKG
CODE
MAX1415ENE*
-45°C to +85°C 16 PDIP
3
P16-1
MAX1415EWE*
-45°C to +85°C 16 Wide SO
3
W16-1
MAX1415EUE
-45°C to +85°C 16 TSSOP
3
U16-1
MAX1415AENE* -45°C to +85°C 16 PDIP
3
P16-1
MAX1415AEWE* -45°C to +85°C 16 Wide SO
3
W16-1
MAX1415AEUE* -45°C to +85°C 16 TSSOP
3
U16-1
MAX1415CNE*
0°C to +70°C 16 PDIP
3
P16-1
MAX1415CWE*
0°C to +70°C 16 Wide SO
3
W16-1
MAX1415CUE*
0°C to +70°C 16 TSSOP
3
U16-1
*Future product—contact factory for availability.
Ordering Information continued at end of data sheet.
Weigh Scales
Pin Configuration
Strain-Gauge Measurements
Loop-Powered Systems
Flow and Gas Meters
Medical Instrumentation
Pressure Transducers
Thermocouple Measurements
RTD Measurements
SPI/QSPI are trademarks of Motorola, Inc.
MICROWIRE is a trademark of National Semiconductor Corp.
TOP VIEW
SCLK 1
16 GND
CLKIN 2
15 VDD
CLKOUT 3
CS 4
RESET 5
14 DIN
MAX1415
MAX1416
13 DOUT
12 DRDY
AIN2+ 6
11 AIN2-
AIN1+ 7
10 REF-
AIN1- 8
9
REF+
PDIP/SO/TSSOP
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
MAX1415/MAX1416
General Description
MAX1415/MAX1416
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
ABSOLUTE MAXIMUM RATINGS
VDD to GND ..............................................................-0.3V to +6V
All Other Pins to GND.................................-0.3V to (VDD + 0.3V)
Maximum Current Input into Any Pin ..................................50mA
Continuous Power Dissipation (TA = +70°C)
16-Pin PDIP (derate 10.5mW/°C above +70°C)...........842mW
16-Pin TSSOP (derate 9.4mW/°C above +70°C) .........755mW
16-Pin Wide SO (derate 9.5mW/°C above +70°C) ......762mW
Operating Temperature Range ..........................-40°C to +85°C
Storage Temperature Range .............................-60°C to +150°C
Junction Temperature ......................................................+150°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS—MAX1415
(VDD = 3V, GND = 0, VREF+ = 1.225V, VREF- = GND, external fCLKIN = 2.4576MHz, CLKDIV bit = 0, CREF+ to GND = 0.1µF, CREF- to
GND = 0.1µF, TA = TMIN to TMAX, unless otherwise noted.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DC ACCURACY
Resolution (No Missing Codes)
16
Output Noise
Integral Nonlinearity
Bits
(Tables 1, 3)
INL
After calibration
Unipolar Offset Drift
(Note 2)
Bipolar Zero Error
±0.0015
Gain = 1, bipolar mode, unbuffered
Unipolar Offset Error
µV
After calibration
%FSR
(Note 1)
µV
0.5
µV/°C
(Note 1)
µV
Gain = 1 to 4
0.5
Gain = 8 to 128
0.1
Positive Full-Scale Error
After calibration
(Notes 1, 3)
µV
Full-Scale Drift
(Notes 2, 4)
0.5
µV/°C
Gain Error
After calibration
(Notes 1, 5)
µV
Gain Drift
(Notes 2, 6)
0.5
ppm of
FSR/°C
±0.003
%FSR
Bipolar Zero Drift (Note 2)
Bipolar Negative Full-Scale Error
After calibration
Bipolar Negative Full-Scale Drift
(Note 2)
Gain = 1 to 4
µV/°C
1
Gain = 8 to 128
µV/°C
0.6
ANALOG INPUTS (AIN1+, AIN1-, AIN2+, AIN2-)
0
VREF /
GAIN
Bipolar input range
-VREF /
GAIN
VREF /
GAIN
Unbuffered
GND 30mV
VDD +
30mV
Buffered
GND +
50mV
VDD 1.5V
Unipolar input range
AIN Differential Input Voltage
Range (Note 7)
V
AIN Absolute Input Voltage
Range (Note 8)
AIN DC Leakage Current
2
V
Unselected input channel
_______________________________________________________________________________________
1
nA
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
(VDD = 3V, GND = 0, VREF+ = 1.225V, VREF- = GND, external fCLKIN = 2.4576MHz, CLKDIV bit = 0, CREF+ to GND = 0.1µF, CREF- to
GND = 0.1µF, TA = TMIN to TMAX, unless otherwise noted.)
PARAMETER
SYMBOL
AIN Input Capacitance
AIN Input Sampling Rate
fs
CONDITIONS
MIN
TYP
Gain = 1
34
Gain = 2
38
Gain = 4
45
Gain = 8 to 128
60
MAX
pF
fCLKIN /
64
Gain = 1 to 128
UNITS
MHz
Gain = 1
105
Gain = 2
110
Gain = 4
120
Gain = 8 to 128
130
Normal-Mode 50Hz Rejection
For filter notches of 25Hz, 50Hz,
±0.02 × fNOTCH
98
dB
Normal-Mode 60Hz Rejection
For filter notches of 20Hz, 60Hz,
±0.02 × fNOTCH
98
dB
Common-Mode 50Hz Rejection
For filter notches of 25Hz, 50Hz,
±0.02 × fNOTCH
150
dB
Common-Mode 60Hz Rejection
For filter notches of 20Hz, 60Hz,
±0.02 × fNOTCH
150
dB
Input Common-Mode Rejection
CMR
dB
EXTERNAL REFERENCE (REF+, REF-)
REF Differential Input Range
VREF
(Note 9)
REF Absolute Input Voltage
Range
REF Input Capacitance
REF Input Sampling Rate
1.00
1.75
V
GND
VDD
V
Gain = 1 to 128
10
pF
fCLKIN /
64
fs
MHz
DIGITAL INPUTS (DIN, SCLK, CS, RESET)
Input High Voltage
VIH
Input Low Voltage
VIL
Input Hysteresis
VHYST
Input Current
2.0
V
0.4
DIN, CS, RESET
250
SCLK
500
mV
±1
IIN
Input Capacitance
V
5
µA
pF
CLKIN INPUT
CLKIN Input High Voltage
VCLKINH
CLKIN Input Low Voltage
VCLKINL
0.4
V
ICLKIN
±10
µA
CLKIN Input Current
2.5
V
DIGITAL OUTPUTS (DOUT, DRDY, CLKOUT)
Output-Voltage Low
VOL
DOUT and DRDY, ISINK = 100µA
0.4
CLKOUT, ISINK = 10µA
0.4
V
_______________________________________________________________________________________
3
MAX1415/MAX1416
ELECTRICAL CHARACTERISTICS—MAX1415 (continued)
MAX1415/MAX1416
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
ELECTRICAL CHARACTERISTICS—MAX1415 (continued)
(VDD = 3V, GND = 0, VREF+ = 1.225V, VREF- = GND, external fCLKIN = 2.4576MHz, CLKDIV bit = 0, CREF+ to GND = 0.1µF, CREF- to
GND = 0.1µF, TA = TMIN to TMAX, unless otherwise noted.)
PARAMETER
Output-Voltage High
Tri-State Leakage Current
Tri-State Output Capacitance
SYMBOL
CONDITIONS
MIN
DOUT and DRDY, ISOURCE = 100µA
VDD 0.6V
CLKOUT, ISOURCE = 10µA
VDD 0.6V
TYP
MAX
UNITS
V
VOH
IL
DOUT only
COUT
DOUT only
±10
9
µA
pF
SYSTEM CALIBRATION
Full-Scale Calibration Range
GAIN = selected PGA gain (1 to 128)
(Note 10)
-1.05 ×
VREF /
GAIN
1.05 ×
VREF /
GAIN
V
Offset Calibration Range
GAIN = selected PGA gain (1 to 128)
(Note 10)
-1.05 ×
VREF /
GAIN
1.05 ×
VREF /
GAIN
V
Input Span
GAIN = selected PGA gain (1 to 128)
(Notes 10, 11)
0.8 ×
VREF /
GAIN
2.1 ×
VREF /
GAIN
V
3.6
V
POWER REQUIREMENTS
Power-Supply Voltage
Power-Supply Current (Note 12)
VDD
IDD
2.7
Unbuffered, fCLKIN = 1MHz, gain = 1 to 128
0.40
Buffered, fCLKIN = 1MHz, gain = 1 to 128
0.725
Unbuffered,
fCLKIN = 2.4576MHz
Gain = 1 to 4
0.55
Gain = 8 to 128
0.55
Buffered,
fCLKIN = 2.4576MHz
Gain = 1 to 4
0.825
Gain = 8 to 128
1.0
Power-down mode (Note 13)
Power-Supply Rejection Ratio
PSRR
mA
8
VDD = 2.7V to 3.6V
(Note 14)
µA
dB
EXTERNAL-CLOCK TIMING SPECIFICATIONS
CLKIN Frequency
fCLKIN
(Note 15)
Duty Cycle
400
2500
kHz
40
60
%
INTERNAL-CLOCK TIMING SPECIFICATIONS
Internal-Clock Frequency
fCLK
MAX1415AE__,
fCLK = 1MHz (CLK = 0)
or 2.4576MHz (CLK = 1)
TA = -40°C to
+85°C
±4
MAX1415C__,
fCLK = 1MHz (CLK = 0)
or 2.4576MHz (CLK = 1)
TA = 0°C to
+70°C
±4
TA = -40°C to 0°C
±7
TA = 0°C to +85°C
±4
MAX1415E__,
fCLK = 1MHz (CLK = 0)
or 2.4576MHz (CLK = 1)
4
_______________________________________________________________________________________
%
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
(VDD = 3V, GND = 0, VREF+ = 1.225V, VREF- = GND, external fCLKIN = 2.4576MHz, CLKDIV bit = 0, CREF+ to GND = 0.1µF, CREF- to
GND = 0.1µF, TA = TMIN to TMAX, unless otherwise noted.)
PARAMETER
Typical Conversion-Time
Variation
SYMBOL
∆tCONV
CONDITIONS
MIN
tCONV = 1/ODR
TYP
MAX
±0.5
UNITS
%
TIMING CHARACTERISTICS—MAX1415
(Note 16) (Figures 8, 9)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
500/
DRDY High Time
s
fCLKIN
Reset Pulse-Width Low
UNITS
100
ns
DRDY Fall to CS Fall Setup Time
t1
0
ns
CS Fall to SCLK Rise Setup Time
t2
120
ns
SCLK Fall to DOUT Valid Delay
t3
0
SCLK Pulse-Width High
t4
100
ns
SCLK Pulse-Width Low
t5
100
ns
CS Rise to SCLK Rise Hold Time
t6
0
ns
Bus Relinquish Time After SCLK
Rising Edge
t7
SCLK Fall to DRDY Rise Delay
t8
DIN to SCLK Setup Time
t9
30
ns
DIN to SCLK Hold Time
t10
20
ns
100
100
100
ns
ns
ns
ELECTRICAL CHARACTERISTICS—MAX1416
(VDD = 5V, GND = 0, VREF+ = 2.5V, VREF- = GND, fCLKIN = 2.4576MHz, CLKDIV bit = 0, CREF+ to GND = 0.1µF, CREF- to GND =
0.1µF, TA = TMIN to TMAX, unless otherwise noted.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DC ACCURACY
Resolution (No Missing Codes)
16
Output Noise
Bits
(Tables 1, 3)
Integral Nonlinearity
INL
After calibration
Unipolar Offset Drift
(Note 2)
Bipolar Zero Error
After calibration
Bipolar Zero Drift (Note 2)
±0.0015
Gain = 1, bipolar mode, unbuffered
Unipolar Offset Error
µV
%FSR
(Note 1)
µV
0.5
µV/°C
(Note 1)
µV
Gain = 1 to 4
0.5
Gain = 8 to 128
0.1
µV/°C
_______________________________________________________________________________________
5
MAX1415/MAX1416
ELECTRICAL CHARACTERISTICS—MAX1415 (continued)
MAX1415/MAX1416
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
ELECTRICAL CHARACTERISTICS—MAX1416 (continued)
(VDD = 5V, GND = 0, VREF+ = 2.5V, VREF- = GND, fCLKIN = 2.4576MHz, CLKDIV bit = 0, CREF+ to GND = 0.1µF, CREF- to GND =
0.1µF, TA = TMIN to TMAX, unless otherwise noted.)
PARAMETER
SYMBOL
CONDITIONS
Positive Full-Scale Error
After calibration
Full-Scale Drift
(Notes 2, 4)
Gain Error
After calibration
Gain Drift
MIN
(Notes 2, 6)
Bipolar Negative Full-Scale Error
After calibration
Bipolar Negative Full-Scale Drift
(Note 2)
Gain = 1 to 4
TYP
MAX
µV
0.5
µV/°C
(Notes 1, 5)
µV
0.5
ppm of
FSR/°C
±0.003
%FSR
1
Gain = 8 to 128
UNITS
(Notes 1, 3)
µV/°C
0.6
ANALOG INPUTS (AIN1+, AIN1-, AIN2+, AIN2-)
0
VREF /
GAIN
Bipolar input range
-VREF /
GAIN
VREF /
GAIN
Unbuffered
GND 30mV
VDD +
30mV
Buffered
GND +
50mV
VDD 1.5V
Unipolar input range
AIN Differential Input Voltage
Range (Note 7)
V
AIN Absolute Input Voltage
Range (Note 8)
V
AIN DC Leakage Current
Unselected input channel
AIN Input Capacitance
AIN Input Sampling Rate
fs
1
Gain = 1
34
Gain = 2
38
Gain = 4
45
Gain = 8 to 128
60
pF
fCLKIN /
64
Gain = 1 to 128
nA
MHz
Gain = 1
96
Gain = 2
105
Gain = 4
110
Gain = 8 to 128
130
Normal-Mode 50Hz Rejection
For filter notches of 25Hz, 50Hz,
±0.02 × fNOTCH
98
dB
Normal-Mode 60Hz Rejection
For filter notches of 20Hz, 60Hz,
±0.02 × fNOTCH
98
dB
Common-Mode 50Hz Rejection
For filter notches of 25Hz, 50Hz,
±0.02 × fNOTCH
150
dB
Common-Mode 60Hz Rejection
For filter notches of 20Hz, 60Hz,
±0.02 × fNOTCH
150
dB
Input Common-Mode Rejection
6
CMR
_______________________________________________________________________________________
dB
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
(VDD = 5V, GND = 0, VREF+ = 2.5V, VREF- = GND, fCLKIN = 2.4576MHz, CLKDIV bit = 0, CREF+ to GND = 0.1µF, CREF- to GND =
0.1µF, TA = TMIN to TMAX, unless otherwise noted.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
EXTERNAL REFERENCE (REF+, REF-)
REF Differential Input Range
REF Absolute Input Voltage
VREF
REF Input Capacitance
REF Input Sampling Rate
(Note 9)
1
3.5
V
GND
VDD
V
Gain = 1 to 128
10
pF
fCLKIN /
64
fs
MHz
DIGITAL INPUTS (DIN, SCLK, CS, RESET)
Input High Voltage
VIH
Input Low Voltage
VIL
Input Hysteresis
VHYST
Input Current
2
V
0.8
DIN, CS, RESET
250
SCLK
500
mV
±1
IIN
Input Capacitance
V
5
µA
pF
CLKIN INPUT
CLKIN Input High Voltage
VCLKINH
CLKIN Input Low Voltage
VCLKINL
0.8
V
ICLKIN
±10
µA
CLKIN Input Current
3.5
V
DIGITAL OUTPUTS (DOUT, DRDY, CLKOUT)
Output-Voltage Low
VOL
Output-Voltage High
VOH
Tri-State Leakage Current
Tri-State Output Capacitance
DOUT and DRDY, ISINK = 800µA
0.4
CLKOUT, ISINK = 10µA
0.4
DOUT and DRDY, ISOURCE = 200µA
4.0
CLKOUT, ISOURCE = 10µA
4.0
IL
DOUT only
COUT
DOUT only
V
V
±10
9
µA
pF
SYSTEM CALIBRATION
Full-Scale Calibration Range
GAIN = selected PGA gain (1 to 128)
(Note 10)
-1.05 ×
VREF /
GAIN
+1.05 ×
VREF /
GAIN
V
Offset Calibration Range
GAIN = selected PGA gain (1 to 128)
(Note 10)
-1.05 ×
VREF /
GAIN
+1.05 ×
VREF /
GAIN
V
Input Span
GAIN = selected PGA gain (1 to 128)
(Notes 10, 11)
0.8 ×
VREF /
GAIN
2.1 ×
VREF /
GAIN
V
4.75
5.25
V
POWER REQUIREMENTS
Power-Supply Voltage
VDD
_______________________________________________________________________________________
7
MAX1415/MAX1416
ELECTRICAL CHARACTERISTICS—MAX1416 (continued)
MAX1415/MAX1416
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
ELECTRICAL CHARACTERISTICS—MAX1416 (continued)
(VDD = 5V, GND = 0, VREF+ = 2.5V, VREF- = GND, fCLKIN = 2.4576MHz, CLKDIV bit = 0, CREF+ to GND = 0.1µF, CREF- to GND =
0.1µF, TA = TMIN to TMAX, unless otherwise noted.)
PARAMETER
Power-Supply Current (Note 12)
SYMBOL
IDD
CONDITIONS
MIN
TYP
0.45
Buffered, fCLKIN = 1MHz, gain = 1 to 128
0.78
Unbuffered,
fCLKIN = 2.4576MHz
Gain = 1 to 4
0.6
Gain = 8 to 128
0.6
Buffered,
fCLKIN = 2.4576MHz
Gain = 1 to 4
0.95
Gain = 8 to 128
1.1
Power-down mode (Note 13)
Power-Supply Rejection Ratio
PSRR
MAX
Unbuffered, fCLKIN = 1MHz, gain = 1 to 128
16
VDD = 4.75V to 5.25V
(Note 14)
UNITS
mA
µA
dB
EXTERNAL-CLOCK SPECIFICATIONS
CLKIN Frequency
fCLKIN
(Note 15)
Duty Cycle
400
2500
kHz
40
60
%
INTERNAL-CLOCK TIMING SPECIFICATIONS
Internal-Clock Frequency
fCLK
MAX1416AE__,
fCLK = 1MHz (CLK = 0)
or 2.4576MHz (CLK = 1)
TA = -40°C to
+85°C
±4
MAX1416C__,
fCLK = 1MHz (CLK = 0)
or 2.4576MHz (CLK = 1)
TA = 0°C to
+70°C
±4
TA = -40°C to 0°C
±7
TA = 0°C to +85°C
±4
MAX1416E__,
fCLK = 1MHz (CLK = 0)
or 2.4576MHz (CLK = 1)
Typical Conversion-Time
Variation
∆tCONV
tCONV = 1/ODR,
CLK = 0 (1MHz), INTCLK = 1
±0.5
%
%
TIMING CHARACTERISTICS—MAX1416
(Note 16) (Figures 8, 9)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
500 /
fCLKIN
DRDY High Time
Reset Pulse-Width Low
UNITS
s
100
ns
DRDY Fall to CS Fall Setup Time
t1
0
ns
CS Fall to SCLK Rise Setup Time
t2
120
ns
SCLK Fall to DOUT Valid Delay
t3
0
SCLK Pulse-Width High
t4
100
ns
SCLK Pulse-Width Low
t5
100
ns
CS Rise to SCLK Rise Hold Time
t6
0
ns
Bus Relinquish Time After SCLK
Rising Edge
t7
60
ns
SCLK Fall to DRDY Rise Delay
t8
100
ns
8
_______________________________________________________________________________________
80
ns
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
(Note 16) (Figures 8, 9)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DIN to SCLK Setup Time
t9
30
ns
DIN to SCLK Hold Time
t10
20
ns
Note 1: These errors are in the order of the conversion noise shown in Tables 1 and 3. This applies after calibration at the given
temperature.
Note 2: Recalibration at any temperature removes these drift errors.
Note 3: Positive full-scale error includes zero-scale errors (unipolar offset error or bipolar zero error) and applies to both unipolar
and bipolar input ranges.
Note 4: Full-scale drift includes zero-scale drift (unipolar offset drift or bipolar zero drift) and applies to both unipolar and bipolar
input ranges.
Note 5: Gain error does not include zero-scale errors. It is calculated as (full-scale error – unipolar offset error) for unipolar ranges,
and (full-scale error – bipolar zero error) for bipolar ranges.
Note 6: Gain-error drift does not include unipolar offset drift or bipolar zero drift. Effectively, it is the drift of the part if only zeroscale calibrations are performed.
Note 7: The analog input voltage range on AIN+ is given here with respect to the voltage on AIN- on the MAX1415/MAX1416.
Note 8: This common-mode voltage range is allowed, provided that the input voltage on the analog inputs does not go more positive than (VDD + 30mV) or more negative than (GND - 30mV). Parts are functional with voltages down to (GND - 200mV),
but with increased leakage at high temperature.
Note 9: The REF differential voltage, VREF, is the voltage on REF+ referenced to REF- (VREF = VREF+ - VREF-).
Note 10: Guaranteed by design.
Note 11: These calibration and span limits apply, provided that the absolute voltage on the analog inputs does not exceed (VDD +
30mV) or go more negative than (GND - 30mV). The offset-calibration limit applies to both the unipolar zero point and the
bipolar zero point.
Note 12: When using a crystal or ceramic resonator across the CLKIN and CLKOUT as the clock source for the device, the supply
current and power dissipation varies depending on the crystal or resonator type. Supply current is measured with the digital inputs connected to 0 or VDD, CLKIN connected to an external clock source, and CLKDIS = 1.
Note 13: If the external master clock continues to run in power-down mode, the power-down current typically increases to 67µA at
3V. When using a crystal or ceramic resonator across the CLKIN and CLKOUT as the clock source for the device, the
clock generator continues to run in power-down mode and the power dissipation depends on the crystal or resonator type
(see the Power-Down Modes section).
Note 14: Measured at DC and applied in the selected passband. PSRR at 50Hz exceeds 120dB with filter notches of 25Hz or 50Hz.
PSRR at 60Hz exceeds 120dB with filter notches of 20Hz or 60Hz.
PSRR depends on both gain and VDD.
GAIN
PSRR (VDD = 5V)
PSRR (VDD = 3V)
(dB)
1
90
86
2
78
78
4
84
85
8 to 128
91
93
Note 15: Provide fCLKIN whenever the MAX1415/MAX1416 are not in power-down mode. If no clock is present, the device can draw
higher-than-specified current and can possibly become uncalibrated.
Note 16: All input signals are specified with tr = tf = 5ns (10% to 90% of VDD) and timed from a voltage level of 1.6V.
_______________________________________________________________________________________
9
MAX1415/MAX1416
TIMING CHARACTERISTICS—MAX1416 (continued)
MAX1415/MAX1416
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
Table 1. MAX1415—Output RMS Noise vs. Gain and Output Data Rate (3V)
FILTER FIRST NOTCH
AND OUTPUT DATA
RATE (Hz)
TYPICAL OUTPUT RMS NOISE (µV)
-3dB FREQUENCY
(Hz)
GAIN
1
2
4
8
16
32
64
128
2.85
1.63
2.16
0.70
0.67
0.63
0.64
0.62
0.70
BUFFERED (fCLKIN = 1MHz)
20
5.24
25
6.55
3.46
1.92
1.13
6.05
0.75
0.73
0.70
100
26.2
48.94
26.98
11.99
0.85
3.44
2.27
1.66
1.72
200
52.4
270.91
161.33
66.19
32.64
16.89
8.34
4.98
4.86
20
5.24
3.09
1.70
1.05
0.72
0.66
0.64
0.60
0.60
0.70
UNBUFFERED (fCLKIN = 1MHz)
25
6.55
3.58
1.94
1.23
0.80
0.77
0.73
0.70
100
26.2
51.92
24.54
11.47
6.14
3.26
2.16
1.67
1.64
200
52.4
263.86
136.78
65.40
34.51
16.64
8.97
4.96
4.80
BUFFERED (fCLKIN = 2.4576MHz)
50
13.1
3.03
1.97
1.34
1.01
0.95
0.93
0.96
0.95
60
15.72
3.62
2.14
1.52
1.05
0.98
1.03
1.04
1.00
250
65.5
51.02
25.44
12.95
6.19
3.84
2.70
2.35
2.23
500
131
280.58
138.29
70.21
34.60
18.44
9.45
5.40
5.34
UNBUFFERED (fCLKIN = 2.4576MHz)
10
50
13.1
3.76
1.63
0.96
0.69
0.66
0.64
0.59
0.61
60
15.72
3.11
1.86
1.12
0.78
0.75
0.71
0.71
0.69
250
65.5
48.28
25.13
12.75
6.18
3.32
2.12
1.59
1.62
500
131
280.67
143.15
75.84
34.70
17.88
9.19
4.90
4.98
______________________________________________________________________________________
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
MAX1415/MAX1416
Table 2. MAX1415—Peak-to-Peak Resolution vs. Gain and Output Data Rate (3V)
FILTER FIRST NOTCH
AND OUTPUT DATA
RATE
(Hz)
TYPICAL PEAK-TO-PEAK RESOLUTION (BITS)
-3dB FREQUENCY
(Hz)
GAIN
1
2
4
8
16
32
64
128
BUFFERED (fCLKIN = 1MHz)
20
5.24
16
16
16
16
15
14
13
12
25
6.55
16
16
16
12
15
14
13
12
100
26.2
12
12
12
16
12
12
11
11
200
52.4
10
10
10
10
10
10
10
9
20
5.24
16
16
16
16
15
14
13
12
UNBUFFERED (fCLKIN = 1MHz)
25
6.55
16
16
16
16
15
14
13
12
100
26.2
12
12
12
12
12
12
12
11
200
52.4
10
10
10
10
10
10
10
9
BUFFERED (fCLKIN = 2.4576MHz)
50
13.1
16
16
16
15
15
14
13
12
60
15.72
16
16
16
15
14
13
12
11
250
65.5
12
12
12
12
12
12
11
10
500
131
10
10
10
10
10
10
10
9
UNBUFFERED (fCLKIN = 2.4576MHz)
50
13.1
16
16
16
16
15
14
13
12
60
15.72
16
16
16
16
15
14
13
12
250
65.5
12
12
12
12
12
12
12
11
500
131
10
10
10
10
10
10
10
9
______________________________________________________________________________________
11
MAX1415/MAX1416
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
Table 3. MAX1416—Output RMS Noise vs. Gain and Output Data Rate (5V)
FILTER FIRST NOTCH
AND OUTPUT DATA
RATE (Hz)
TYPICAL OUTPUT RMS NOISE (µV)
-3dB FREQUENCY
(Hz)
GAIN
1
2
4
8
16
32
64
128
3.51
1.87
1.11
0.75
0.70
0.71
0.67
0.65
0.74
BUFFERED (fCLKIN = 1MHz)
20
5.24
25
6.55
4.46
2.39
1.32
0.90
0.83
0.81
0.75
100
26.2
92.29
47.60
28.62
11.60
6.40
3.70
2.34
2.30
200
52.4
552.57
295.67
105.50
69.01
35.15
17.37
9.04
9.05
20
5.24
3.88
1.92
1.17
0.76
0.72
0.70
0.65
0.65
0.74
UNBUFFERED (fCLKIN = 1MHz)
25
6.55
5.00
2.60
1.41
0.87
0.83
0.81
0.73
100
26.2
98.13
48.60
24.35
11.89
6.00
3.66
2.51
2.46
200
52.4
551.95
275.15
134.65
69.82
33.34
16.77
9.04
9.36
BUFFERED (fCLKIN = 2.4576MHz)
50
13.1
4.10
2.56
1.68
1.23
1.19
1.21
1.15
1.19
60
15.72
4.52
2.96
1.89
1.32
1.32
1.27
1.28
1.31
250
65.5
96.62
47.35
26.33
12.42
7.10
4.30
3.16
3.19
500
131
568.80
292.49
151.10
71.96
36.61
19.18
9.95
10.23
UNBUFFERED (fCLKIN = 2.4576MHz)
12
50
13.1
3.21
1.84
1.14
0.76
0.73
0.72
0.64
0.65
60
15.72
3.93
2.21
1.37
0.87
0.81
0.77
0.74
0.73
250
65.5
99.77
52.91
26.56
12.31
5.95
3.50
2.37
2.38
500
131
520.55
302.42
136.54
68.66
36.94
18.64
9.34
9.49
______________________________________________________________________________________
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
MAX1415/MAX1416
Table 4. MAX1416—Peak-to-Peak Resolution vs. Gain and Output Data Rate (5V)
FILTER FIRST NOTCH
AND OUTPUT DATA
RATE (Hz)
TYPICAL PEAK-TO-PEAK RESOLUTION (BITS)
-3dB FREQUENCY
(Hz)
GAIN
1
2
4
8
16
32
64
128
BUFFERED (fCLKIN = 1MHz)
20
5.24
16
16
16
16
16
15
14
13
25
6.55
16
16
16
16
16
15
14
13
100
26.2
12
12
12
12
12
12
12
11
200
52.4
10
10
11
10
10
10
10
9
20
5.24
16
16
16
16
16
15
14
13
25
6.55
16
16
16
16
16
15
14
13
UNBUFFERED (fCLKIN = 1MHz)
100
26.2
12
12
12
12
12
12
12
11
200
52.4
10
10
10
10
10
10
10
9
BUFFERED (fCLKIN = 2.4576MHz)
50
13.1
16
16
16
16
15
14
13
12
60
15.72
16
16
16
16
15
14
13
12
250
65.5
12
12
12
12
12
12
12
10
500
131
10
10
10
10
10
10
10
9
UNBUFFERED (fCLKIN = 2.4576MHz)
50
13.1
16
16
16
16
16
15
14
13
60
15.72
16
16
16
16
16
15
14
13
250
65.5
12
12
12
12
12
12
12
11
500
131
10
10
10
10
10
10
10
9
______________________________________________________________________________________
13
Typical Operating Characteristics
(MAX1415: VDD = 5V, VREF+ = 2.5V, VREF- = GND, TA = +25°C, unless otherwise noted.) (MAX1416: VDD = 3V, VREF+ = 1.225V,
VREF- = GND, TA = +25°C, unless otherwise noted.)
TYPICAL OUTPUT NOISE
(MAX1416, BUFFERED MODE)
RMS NOISE = 1.3µV
300
OCCURRENCE
CODE READ
32770
VDD = 5V, VREF = 2.5V
GAIN = 128
ODR = 60Hz
32768
32766
32764
32762
200
0.0015
MAX1415/MAX1416 toc03
32772
400
OFFSET ERROR vs. SUPPLY VOLTAGE
(MAX1415)
0.0010
OFFSET ERROR (%FSR)
GAIN = 128
ODR = 60Hz
RMS NOISE = 1.3µV
MAX1415/MAX1416 toc02
VDD = 5V,
VREF = 2.5V
32774
HISTOGRAM OF TYPICAL OUTPUT NOISE
(MAX1416, BUFFERED MODE)
MAX1415/MAX1416 toc01
32776
0.0005
0
-0.0005
100
32760
-0.0010
32758
32756
1600
2000
-0.0015
READING NUMBER
2.70
OFFSET ERROR vs. SUPPLY VOLTAGE
(MAX1416)
0
-0.001
MAX1416
0.001
0
MAX1415
-0.001
4.85
4.95
5.05
-15
10
35
0.0010
0.0005
0
-0.0005
85
60
2.70
2.85
0.001
0
-0.001
0.005
0.004
0.003
GAIN ERROR (%FSR)
0.002
3.15
3.30
GAIN ERROR vs. TEMPERATURE
MAX1415/MAX1416 toc07
0.003
3.00
SUPPLY VOLTAGE (V)
GAIN ERROR vs. SUPPLY VOLTAGE
(MAX1416)
GAIN ERROR (%FSR)
0.0015
TEMPERATURE (°C)
SUPPLY VOLTAGE (V)
MAX1415
0.002
0.001
0
-0.001
-0.002
MAX1416
-0.003
-0.002
-0.004
-0.005
-0.003
4.75
4.85
4.95
5.05
SUPPLY VOLTAGE (V)
14
3.60
-0.0015
-40
5.25
5.15
3.45
-0.0010
-0.003
-0.003
3.30
GAIN ERROR vs. SUPPLY VOLTAGE
(MAX1415)
-0.002
-0.002
3.15
MAX1415/MAX1416 toc06
0.001
0.002
OFFSET ERROR (%FSR)
0.002
0.003
3.00
SUPPLY VOLTAGE (V)
OFFSET ERROR vs. TEMPERATURE
MAX1415/MAX1416 toc04
0.003
4.75
2.85
CODE
MAX1415/MAX1416 toc08
1200
GAIN ERROR (%FSR)
800
MAX1415/MAX1416 toc05
400
32760
32761
32762
32763
32764
32765
32766
32767
32768
32769
32770
32771
32772
32773
0
0
OFFSET ERROR (%FSR)
MAX1415/MAX1416
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
5.15
5.25
-40
-15
10
35
60
TEMPERATURE (°C)
______________________________________________________________________________________
85
3.45
3.60
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
SUPPLY CURRENT vs. SUPPLY VOLTAGE
(MAX1415)
0.5
B
0.4
C
D
0.3
0.65
MAX1415/MAX1416 toc10
SUPPLY CURRENT (mA)
A
SUPPLY CURRENT (mA)
MAX1415/MAX1416 toc09
0.6
SUPPLY CURRENT vs. SUPPLY VOLTAGE
(MAX1416)
A
B
0.55
0.45
C
D
0.35
E
E
0.2
0.25
2.70
2.85
3.00
3.15
3.30
3.45
3.60
4.75
4.85
4.95
5.05
5.15
5.25
SUPPLY VOLTAGE (V)
A: BUFFERED MODE
B: BUFFERED MODE C: BUFFERED MODE
fCLKIN = 2.4576MHz,
fCLKIN = 2.4576MHz, fCLKIN = 1MHz,
GAIN = 8 TO 128
GAIN = 1 TO 4
GAIN = 1 TO 128
SUPPLY VOLTAGE (V)
A: BUFFERED MODE
B: BUFFERED MODE C: BUFFERED MODE
fCLKIN = 2.4576MHz,
fCLKIN = 2.4576MHz, fCLKIN = 1MHz,
GAIN = 8 TO 128
GAIN = 1 TO 4
GAIN = 1 TO 128
D: UNBUFFERED MODE E: UNBUFFERED MODE
fCLKIN = 2.4576MHz,
fCLKIN = 1MHz,
GAIN = 1 TO 128
GAIN = 1 TO 128
D: UNBUFFERED MODE E: UNBUFFERED MODE
fCLKIN = 2.4576MHz,
fCLKIN = 1MHz,
GAIN = 1 TO 128
GAIN = 1 TO 128
SUPPLY CURRENT vs. TEMPERATURE
(MAX1415)
0.5
B
C
0.4
D
0.3
MAX1415/MAX1416 toc12
SUPPLY CURRENT (mA)
A
0.65
SUPPLY CURRENT (mA)
MAX1415/MAX1416 toc11
0.6
SUPPLY CURRENT vs. TEMPERATURE
(MAX1416)
A
B
0.55
C
0.45
D
0.35
E
E
0.2
0.25
-40
-15
10
35
60
85
-40
-15
10
35
60
85
TEMPERATURE (°C)
A: BUFFERED MODE
B: BUFFERED MODE C: BUFFERED MODE
fCLKIN = 2.4576MHz,
fCLKIN = 2.4576MHz, fCLKIN = 1MHz,
GAIN = 8 TO 128
GAIN = 1 TO 4
GAIN = 1 TO 128
TEMPERATURE (°C)
A: BUFFERED MODE
B: BUFFERED MODE C: BUFFERED MODE
fCLKIN = 2.4576MHz,
fCLKIN = 2.4576MHz, fCLKIN = 1MHz,
GAIN = 8 TO 128
GAIN = 1 TO 4
GAIN = 1 TO 128
D: UNBUFFERED MODE E: UNBUFFERED MODE
fCLKIN = 2.4576MHz,
fCLKIN = 1MHz,
GAIN = 1 TO 128
GAIN = 1 TO 128
D: UNBUFFERED MODE E: UNBUFFERED MODE
fCLKIN = 2.4576MHz,
fCLKIN = 1MHz,
GAIN = 1 TO 128
GAIN = 1 TO 128
______________________________________________________________________________________
15
MAX1415/MAX1416
Typical Operating Characteristics (continued)
(MAX1415: VDD = 5V, VREF+ = 2.5V, VREF- = GND, TA = +25°C, unless otherwise noted.) (MAX1416: VDD = 3V, VREF+ = 1.225V,
VREF- = GND, TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(MAX1415: VDD = 5V, VREF+ = 2.5V, VREF- = GND, TA = +25°C, unless otherwise noted.) (MAX1416: VDD = 3V, VREF+ = 1.225V,
VREF- = GND, TA = +25°C, unless otherwise noted.)
SUPPLY CURRENT vs. fCLKIN
(MAX1415)
0.4
C
D
0.3
MAX1415/MAX1416 toc14
0.5
0.65
B
SUPPLY CURRENT (mA)
B
A
SUPPLY CURRENT vs. fCLKIN
(MAX1416)
MAX1415/MAX1416 toc13
A
0.55
0.45
C
D
0.35
E
E
0.2
0.25
0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6
fCLKIN (MHz)
B: BUFFERED MODE
CLK = 1,
GAIN = 1
A: BUFFERED MODE
CLK = 1,
GAIN = 128
C: BUFFERED MODE
CLK = 0,
GAIN = 1, 128
D: UNBUFFERED MODE E: UNBUFFERED MODE
CLK = 1,
CLK = 0,
GAIN = 1, 128
GAIN = 1, 128
0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6
SUPPLY CURRENT vs. GAIN
(MAX1416)
A, B
0.5
D, E
0.65
A
B
SUPPLY CURRENT (mA)
MAX1415/MAX1416 toc15
0.6
C
C: BUFFERED MODE
CLK = 0,
GAIN = 1, 128
D: UNBUFFERED MODE E: UNBUFFERED MODE
CLK = 1,
CLK = 0,
GAIN = 1, 128
GAIN = 1, 128
SUPPLY CURRENT vs. GAIN
(MAX1415)
0.4
fCLKIN (MHz)
B: BUFFERED MODE
CLK = 1,
GAIN = 1
A: BUFFERED MODE
CLK = 1,
GAIN = 128
0.55
0.45
C
D
E
0.35
0.3
MAX1415/MAX1416 toc16
SUPPLY CURRENT (mA)
0.6
SUPPLY CURRENT (mA)
MAX1415/MAX1416
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
F
F
0.25
0.2
1
16
2
4
8
16
32
64
128
1
2
4
8
16
32
64
128
GAIN
A: BUFFERED MODE
B: BUFFERED MODE C: BUFFERED MODE
CLK = 1, CLKDIV = 1,
CLK = 1, CLKDIV = 0, CLK = 0, CLKDIV = 0,
fCLKIN = 4.9152MHz
fCLKIN = 1MHz
fCLKIN = 2.4576MHz
GAIN
A: BUFFERED MODE
B: BUFFERED MODE C: BUFFERED MODE
CLK = 1, CLKDIV = 1,
CLK = 1, CLKDIV = 0, CLK = 0, CLKDIV = 0,
fCLKIN = 4.9152MHz
fCLKIN = 2.4576MHz fCLKIN = 1MHz
D: UNBUFFERED MODE E: UNBUFFERED MODE F: UNBUFFERED MODE
CLK = 1, CLKDIV = 1, CLK = 1, CLKDIV = 0, CLK = 0, CLKDIV = 0,
fCLKIN = 4.9152MHz
fCLKIN = 2.4576MHz
fCLKIN = 1MHz
D: UNBUFFERED MODE E: UNBUFFERED MODE F: UNBUFFERED MODE
CLK = 1, CLKDIV = 1, CLK = 1, CLKDIV = 0, CLK = 0, CLKDIV = 0,
fCLKIN = 4.9152MHz
fCLKIN = 2.4576MHz
fCLKIN = 1MHz
______________________________________________________________________________________
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
60
40
20
0
POWER-DOWN SUPPLY CURRENT
vs. TEMPERATURE
180
160
140
120
300
250
2.85
3.00
3.15
3.30
3.45
3.60
MAX1415
VDD = 5V
200
150
MAX1416
VDD = 3V
100
100
2.70
50
0
4.75
SUPPLY VOLTAGE (V)
4.85
4.95
5.05
5.15
5.25
-40
SUPPLY VOLTAGE (V)
-15
10
INTERNAL OSCILLATOR STARTUP TIME
MAX1415/MAX1416 toc20
MAX1415/MAX1416 toc21
VDD
5V/div
35
60
85
TEMPERATURE (°C)
EXTERNAL OSCILLATOR STARTUP TIME
16th RISING EDGE OF SCLK
SCLK
5V/div
4.9152MHz CRYSTAL
CLKOUT
5V/div
CLKOUT
5V/div
CLK = 1
CLKOUT
5V/div
CLKOUT
5V/div
CLK = 0
2.4576MHz CRYSTAL
2ms/div
MAX1415/MAX1416 toc19
MAX1415/MAX1416 toc18
80
200
POWER-DOWN SUPPLY CURRENT (nA)
MAX1415/MAX1416 toc17
POWER-DOWN SUPPLY CURRENT (nA)
100
POWER-DOWN SUPPLY CURRENT
vs. SUPPLY VOLTAGE (MAX1416)
POWER-DOWN SUPPLY CURRENT (nA)
POWER-DOWN SUPPLY CURRENT
vs. SUPPLY VOLTAGE (MAX1415)
4µs/div
______________________________________________________________________________________
17
MAX1415/MAX1416
Typical Operating Characteristics (continued)
(MAX1415: VDD = 5V, VREF+ = 2.5V, VREF- = GND, TA = +25°C, unless otherwise noted.) (MAX1416: VDD = 3V, VREF+ = 1.225V,
VREF- = GND, TA = +25°C, unless otherwise noted.)
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
MAX1415/MAX1416
Pin Description
18
PIN
NAME
FUNCTION
1
SCLK
Serial Clock Input. Apply an external serial clock to transfer data to and from the device at data rates
up to 5MHz.
2
CLKIN
Clock Input. Connect a crystal/resonator between CLKIN and CLKOUT, or drive CLKIN externally with
a CMOS-compatible clock source. Connect CLKIN to GND when using the internal oscillator.
3
CLKOUT
Clock Output. Connect a crystal/resonator between CLKIN and CLKOUT. When enabled, CLKOUT
provides a CMOS-compatible, inverted clock output. CLKOUT can drive one CMOS load. Set CLKDIS
= 0 in the clock register to enable CLKOUT. Set CLKDIS = 1 in the clock register to disable CLKOUT.
4
CS
Active-Low Chip-Select Input. CS selects the active device in systems with more than one device on
the serial bus. Drive CS low to clock data in on DIN and to clock data out on DOUT. When CS is high,
DOUT is high impedance. Connect CS to GND for 3-wire operation.
5
RESET
Active-Low Reset Input. Drive RESET low to reset the MAX1415/MAX1416 to power-on reset status.
6
AIN2+
Channel 2 Positive Analog Input
7
AIN1+
Channel 1 Positive Analog Input
8
AIN1-
Channel 1 Negative Analog Input
9
REF+
Positive Reference Input
10
REF-
Negative Reference Input
11
AIN2-
Channel 2 Negative Analog Input
12
DRDY
Active-Low Data Ready Output. DRDY goes low when a new conversion result is available in the data
register. When a read operation of a full output word completes, DRDY returns high.
13
DOUT
Serial Data Output. DOUT outputs serial data from the data register. DOUT changes on the falling
edge of SCLK and is valid on the rising edge of SCLK. When CS is high, DOUT is high impedance.
14
DIN
Serial Data Input. Data on DIN is clocked in on the rising edge of SCLK when CS is low.
15
VDD
Power Input. Connect VDD to a 2.7V to 3.6V power supply for the MAX1415, and connect VDD to a
4.75V to 5.25V power supply for the MAX1416.
16
GND
Ground
______________________________________________________________________________________
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
CLKIN
CLOCK
GENERATOR
BUFFER
CLKOUT
MAX1415
MAX1416
AIN1+
AIN1AIN2+
MUX
S1
S2
PGA
2nd-ORDER
SIGMA-DELTA
MODULATOR
DIGITAL
FILTER
VDD
GND
AIN2BUFFER
S1 AND S2 ARE OPEN IN
BUFFERED MODE AND CLOSED
IN UNBUFFERED MODE
REF+
SERIAL INTERFACE,
REGISTERS,
AND
CONTROL
CS
SCLK
DIN
DOUT
DRDY
RESET
REF-
Detailed Description
The MAX1415/MAX1416 low-power, 2-channel serial
output ADCs use a sigma-delta modulator with a digital
filter to achieve 16-bit resolution with no missing codes.
Each device includes a PGA, an on-chip input buffer,
an internal oscillator, and a bidirectional communications port. The MAX1415 operates with a 2.7V to 3.6V
single supply, and the MAX1416 operates with a 4.75V
to 5.25V single supply.
Fully differential inputs, an internal input buffer, and an
on-chip PGA (gain = 1 to 128) allow low-level signals to
be directly measured, minimizing the requirements for
external signal conditioning. Self-calibration corrects for
gain and offset errors. A programmable digital filter
allows for the selection of the output data rate and first
notch frequency from 20Hz to 500Hz.
The bidirectional serial SPI-/QSPI-/MICROWIRE-compatible interface consists of four digital control lines (SCLK,
CS, DOUT, and DIN) and provides an easy interface to
microcontrollers (µCs). Connect CS to GND to configure
the MAX1415/MAX1416 for 3-wire operation.
Analog Inputs
The MAX1415/MAX1416 accept four analog inputs
(AIN1+, AIN1-, AIN2+, and AIN2-) in buffered or
unbuffered mode. Use Table 8 to select the positive
and negative input pair for a fully differential channel.
The input buffer isolates the inputs from the capacitive
load presented by the PGA/modulator, allowing for high
source-impedance analog transducers. The value of
the BUF bit in the setup register (see the Setup Register
section) determines whether the input buffer is enabled
or disabled.
Internal protection diodes, which clamp the analog
input to VDD and/or GND, allow the input to swing from
(GND - 0.3V) to (VDD + 0.3V), without damaging the
device. If the analog input exceeds 300mV beyond the
supplies, limit the input current to 10mA.
Input Buffers
When the analog input buffer is disabled, the analog
input drives a typical 7pF (gain = 1) capacitor, CTOTAL,
in series with the 7kΩ typical on-resistance of the track
and hold (T/H) switch (Figure 1). CTOTAL is comprised
of the sampling capacitor, CSAMP, and the stray capacitance, CSTRAY. During the conversion, CSAMP charges
to (AIN+ - AIN-). The gain determines the value of
CSAMP (see Table 5).
______________________________________________________________________________________
19
MAX1415/MAX1416
Functional Diagram
To minimize gain errors in unbuffered mode, select a
source impedance less than the maximum values
shown in Figures 2 and 3. These are the maximum
external resistance/capacitance combinations allowed
before gain errors greater than 1 LSB are introduced in
unbuffered mode.
Enable the internal input buffer for a high source impedance. This isolates the inputs from the sampling capacitor and reduces the sampling-related gain error. When
using the internal buffer, limit the absolute input voltage
range to (VGND + 50mV) to (VDD - 1.5V). Properly set
up the gain and common-mode voltage range to minimize linearity errors.
AIN(+)
AIN(-)
CTOTAL(7pF TYP FOR GAIN = 1)
CTOTAL = CSAMP + CSTRAY
VBIAS
Figure 1. Unbuffered Analog Input Structure
Input Voltage Range
Reference
The MAX1415/MAX1416 provide differential inputs,
REF+ and REF-, for an external reference voltage.
Connect the external reference directly across REF+ and
REF- to obtain the differential reference voltage, VREF.
The common-mode voltage range for VREF+ and VREFis between GND and VDD. For specified operation, the
nominal voltage, VREF is 1.225V for the MAX1415 and
2.5V for the MAX1416.
The MAX1415/MAX1416 sample REF+ and REF- at
fCLKIN/64 (CLKDIV = 0) or fCLKIN/128 (CLKDIV = 1)
with an internal 10pF (typ for gain = 1) sampling capacitor in series with a 7kΩ (typ) switch on-resistance.
MAXIMUM EXTERNAL RESISTANCE
vs. MAXIMUM EXTERNAL CAPACITANCE (1MHz)
100
EXTERNAL RESISTANCE (kΩ)
In unbuffered mode, the absolute analog input voltage
range is from (GND - 30mV) to (VDD + 30mV) (see the
Electrical Characteristics section). In buffered mode,
the analog input voltage range is reduced to (GND +
50mV) to (VDD - 1.5V). In both buffered and unbuffered
modes, the differential analog input range (VAIN+ - VAIN-)
decreases at higher gains (see the Programmable Gain
Amplifier and Unipolar and Bipolar Modes sections).
GAIN = 1
GAIN = 2
10
GAIN = 4
GAIN = 8 TO 128
1
0.1
1
10
100
1000
10,000
EXTERNAL CAPACITANCE (pF)
Figure 2. Maximum External Resistance vs. Maximum External
Capacitance for Unbuffered Mode (1MHz)
MAXIMUM EXTERNAL RESISTANCE
vs. MAXIMUM EXTERNAL CAPACITANCE
(2.4576MHz)
100
Programmable Gain Amplifier
A PGA provides selectable levels of gain: 1, 2, 4, 8, 16,
32, 64, and 128. Bits G0, G1, and G2 in the setup register control the gain (see Table 9). As the gain increases, the value of the input sampling capacitor, CSAMP,
also increases (see Table 5). The dynamic load presented to the analog inputs increases with clock frequency and gain in unbuffered mode (see the Input
Buffers section and Figure 1).
HIGHIMPEDANCE
INPUT
RSW (7kΩ TYP)
EXTERNAL RESISTANCE (kΩ)
MAX1415/MAX1416
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
GAIN = 1
GAIN = 2
10
GAIN = 4
1
GAIN = 8 TO 128
0.1
1
10
100
1000
10,000
EXTERNAL CAPACITANCE (pF)
Figure 3. Maximum External Resistance vs. Maximum External
Capacitance for Unbuffered Mode (2.4576MHz)
20
______________________________________________________________________________________
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
MAX1415/MAX1416
Table 5. Input Sampling Capacitor vs. Gain
2
7.5
4
15
8–128
30
Increasing the gain increases the resolution of the ADC
(LSB size decreases), but reduces the differential input
voltage range. Calculate 1 LSB in unipolar mode using
the following equation:
1111 1111 1111 1101
1111 1111 1111 1100
1 LSB =
0000 0000 0000 0010
0000 0000 0000 0001
0000 0000 0000 0000
0
where: VREF = VREF+ - VREF-.
Unipolar and Bipolar Modes
The B/U bit in the setup register (Table 9) configures
the MAX1415/MAX1416 for unipolar or bipolar transfer
functions. Figures 4 and 5 illustrate the unipolar and
bipolar transfer functions, respectively.
In unipolar mode, the digital output code is straight
binary. When AIN+ = AIN-, the outputs are at zero
scale, which is the lower endpoint of the transfer function. The full-scale endpoint is given by AIN+ - AIN- =
VREF / GAIN, where VREF = VREF+ - VREF-.
In bipolar mode, the digital output code is in offset
binary. Positive full scale is given by AIN+ - AIN- =
+VREF / GAIN and negative full scale is given by AIN+ AIN- = -VREF / GAIN. When AIN+ = AIN-, the outputs
are at zero scale, which is the midpoint of the bipolar
transfer function.
2
3
65,533
DIFFERENTIAL INPUT VOLTAGE (LSB)
65,535
VREF/GAIN
VREF/GAIN
1111 1111 1111 1111
1111 1111 1111 1110
1111 1111 1111 1101
1 LSB =
BINARY OUTPUT CODE
where: VREF = VREF+ - VREF-.
1
Figure 4. MAX1415/MAX1416 Unipolar Transfer Function
Calculate 1 LSB in bipolar mode using the following
equation:
VREF
1 LSB =
× 2
GAIN (65,536)
VREF
(GAIN) (65,536)
0000 0000 0000 0011
VREF
1 LSB =
GAIN (65,536)
For a gain of 1 and VREF = 2.5V, the full-scale voltage
in unipolar mode is 2.5V and 1 LSB ≈ 38.1µV. For a
gain of 4, the full-scale voltage in unipolar mode is
0.625V (VREF/GAIN) and 1 LSB ≈ 9.5µV. The differential
input voltage range in this example reduces from 2.5V
to 0.625V, and the resolution increases since the LSB
size decreases from 38.1µV to 9.5µV.
FULL-SCALE TRANSITION
1111 1111 1111 1110
VREF/GAIN
3.75
VREF/GAIN
1
VREF/GAIN
1111 1111 1111 1111
VREF
(GAIN) (65,536)
x2
1000 0000 0000 0001
1000 0000 0000 0000
0111 1111 1111 1111
VREF/GAIN
INPUT SAMPLING CAPACITOR (CSAMP)
(pF)
BINARY OUTPUT CODE
GAIN
0000 0000 0000 0010
0000 0000 0000 0001
0000 0000 0000 0000
-32,768
-32,766
-1
0
+1
+32,765
+32,767
DIFFERENTIAL INPUT VOLTAGE (LSB)
Figure 5. MAX1415/MAX1416 Bipolar Transfer Function
When the MAX1415/MAX1416 are in buffered mode, the
absolute and common-mode analog input voltage
ranges reduce to between (GND + 50mV) and (VDD 1.5V). The differential input voltage range is not affected
in buffered mode.
______________________________________________________________________________________
21
Modulator
The MAX1415/MAX1416 perform analog-to-digital conversions using a single-bit, 2nd-order, switched-capacitor, sigma-delta modulator. The sigma-delta modulator
converts the input signal into a digital pulse train whose
average duty cycle represents the digitized signal information. A single comparator within the modulator quantizes the input signal at a much higher sample rate than
the bandwidth of the input.
The MAX1415/MAX1416 modulator provides 2nd-order
frequency shaping of the quantization noise resulting
from the single-bit quantizer. The modulator is fully differential for maximum signal-to-noise ratio and minimum susceptibility to power-supply and common-mode
noise. A single-bit data stream is then presented to the
digital filter for processing to remove the frequencyshaped quantization noise.
The modulator sampling frequency is f CLKIN / 128,
regardless of gain, where fCLKIN (CLKDIV = 0) is the
frequency of the signal at CLKIN.
Digital Filtering
The MAX1415/MAX1416 contain an on-chip, digital lowpass filter that processes the 1-bit data stream from the
modulator using a SINC3 (sinx/x)3 response. The SINC3
filter has a settling time of three output data periods.
Filter Characteristics
Figure 6 shows the filter frequency response. The
SINC3 characteristic -3dB cutoff frequency is 0.262
times the first notch frequency. This results in a cutoff
frequency of 15.72Hz for a first filter notch frequency of
60Hz (output data rate of 60Hz). The response shown
in Figure 5 is repeated at either side of the digital filter’s
sample frequency, fM (fM = 19.2kHz for 60Hz output
data rate), and at either side of the related harmonics
(2fM, 3fM, and so on).
0
fCLKIN = 2.4576MHz
CLK = 1
FS1 = 0
FS0 = 1
fN = 60Hz
-20
-40
GAIN (dB)
MAX1415/MAX1416
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
-60
-80
-100
-120
-140
-160
0
The output data rate for the digital filter corresponds with
the positioning of the first notch of the filter’s frequency
response. Therefore, for the plot in Figure 6, where the first
notch of the filter is 60Hz, the output data rate is 60Hz. The
notches of the SINC3 filter are repeated at multiples of the
first notch frequency. The SINC3 filter provides an attenuation of better than 100dB at these notches.
Determine the cutoff frequency of the digital filter by loading the appropriate values into the CLK, FS0, and FS1
bits in the clock register (see Table 13). Programming a
different cutoff frequency with FS0 and FS1 changes the
frequency of the notches, but it does not alter the profile
of the frequency response.
For step changes at the input, allow a settling time
before valid data is read. The settling time depends on
the output data rate chosen for the filter. The worstcase settling time of a SINC3 filter for a full-scale step
input is four times the output data period. By synchronizing the step input using FSYNC, the settling time
reduces to three times the output data period. If FSYNC
is high during the step input, the filter settles in three
times the data output period after FSYNC falls low.
Analog Filtering
The digital filter does not provide any rejection close to
the harmonics of the modulator sample frequency. Due to
the high oversampling ratio of the MAX1415/MAX1416,
these bands occupy only a small fraction of the spectrum
and most broadband noise is filtered. The analog filtering
requirements in front of the MAX1415/MAX1416 are
reduced compared to a conventional converter with no
on-chip filtering. In addition, the devices provide excellent
common-mode rejection to reduce the common-mode
noise susceptibility.
Additional filtering prior to the MAX1415/MAX1416 eliminates unwanted frequencies the digital filter does not
reject. Use additional filtering to ensure that differential
noise signals outside the frequency band of interest do
not saturate the analog modulator.
If passive components are in the path of the analog
inputs when the device is in unbuffered mode, ensure
the source impedance is low enough (Figure 2) not to
introduce gain errors in the system. This significantly
limits the amount of passive anti-aliasing filtering that
can be applied in front of the MAX1415/MAX1416 in
unbuffered mode. In buffered mode, large source
impedance causes a small DC-offset error, which can
be removed by calibration.
20 40 60 80 100 120 140 160 180 200
FREQUENCY (Hz)
Figure 6. Frequency Response of the SINC3 Filter (Notch at
60Hz)
22
______________________________________________________________________________________
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
Internal-Clock Startup Time
The internal clock requires time to stabilize during
power-on reset. This startup time is dependent on the
internal-clock frequency (see the Typical Operating
Characteristics section). The typical startup time for the
internal oscillator is less than 35µs, while the external
oscillator startup time when using a crystal or resonator
is in the order of milliseconds.
MAX1415/MAX1416
Internal Oscillator Mode
In internal oscillator mode (INTCLK = 1), set the CLK bit
in the clock register (Table 12) to 0 to operate at a clock
frequency of 1MHz, or set CLK to 1 for a frequency of
2.4576MHz. The CLKDIV bit is not used in this mode.
CS
t6
t2
SCLK
t10
t9
DIN
MSB
LSB
Figure 8. Write Timing Diagram
External Oscillator
The oscillator requires time to stabilize when enabled.
Startup time for the oscillator depends on supply voltage,
temperature, load capacitances, and center frequency.
Depending on the load capacitance, a 1MΩ feedback
resistor across the crystal can reduce the startup time
(Figure 7). The MAX1415/MAX1416 were tested with an
ECS-24-32-1 (2.4576MHz crystal) and an ECS-49-20-1
(4.9152MHz crystal) (see the Typical Operating Characteristics section). When the external oscillator is
enabled, the supply current is typically 67µA with a 3V
supply and 227µA with a 5V supply.
DRDY
t8
t1
CS
t2
t6
t4
SCLK
t5
t3
DOUT
MSB
t7
LSB
Serial Digital Interface
The MAX1415/MAX1416 interface is fully compatible with
SPI-, QSPI-, and MICROWIRE-standard serial interfaces.
The serial interface provides access to seven on-chip
registers. The registers are 8, 16, and 24 bits in size.
Drive CS low to transfer data in and out of the
MAX1415/MAX1416. Clock in data at DIN on the rising
edge of SCLK. Data at DOUT changes on the falling
edge of SCLK and is valid on the rising edge of SCLK.
DIN and DOUT are transferred MSB first. Drive CS high
to force DOUT high impedance and cause the
MAX1415/MAX1416 to ignore any signals on SCLK and
CRYSTAL OR
CERAMIC
RESONATOR
CLKIN
CL
MAX1415
MAX1416
CLKOUT
CL
OPTIONAL
1MΩ
Figure 7. Using a Crystal or Ceramic Oscillator
Figure 9. Read Timing Diagram
DIN. Connect CS low for 3-wire operation. Figures 8
and 9 show the timings for write and read operations,
respectively.
On-Chip Registers
The MAX1415/MAX1416 contain seven internal registers
(Figure 10), which are accessed by the serial interface.
These registers control the various functions of the device
and allow the results to be read. Table 7 lists the address,
power-on default value, and size of each register.
The first of these registers is the communications register.
The 8-bit communications register controls the acquisition-channel selection, whether the next data transfer is a
read or write operation, and which register is to be
accessed. The second register is the 8-bit setup register,
which controls calibration modes, gain setting,
unipolar/bipolar inputs, and buffered/unbuffered modes.
The third register is the 8-bit clock register, which sets the
digital filter characteristics and the clock control bits. The
fourth register is the 16-bit data register, which holds the
output result. The 24-bit offset and gain registers store the
calibration coefficients for the MAX1415/MAX1416. The 8bit test register is used for factory testing only.
______________________________________________________________________________________
23
MAX1415/MAX1416
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
DIN
Communications Register
The byte-wide communications register is bidirectional
so it can be written and read. The byte written to the
communications register indicates the next read or write
operation on the selected register, the power-down
mode, and the analog input channel (see Table 6). The
DRDY bit indicates the conversion status.
RS2 RS1 RS0
COMMUNICATIONS REGISTER
SETUP REGISTER (8 BITS)
CLOCK REGISTER (8 BITS)
REGISTER
SELECT
DECODER
DATA REGISTER (16 BITS)
DOUT
TEST REGISTER (8 BITS)*
OFFSET REGISTER (24 BITS)
GAIN REGISTER (24 BITS)
*THE TEST REGISTER IS USED FOR FACTORY TESTING ONLY.
Figure 10. Register Summary
The default state of the MAX1415/MAX1416 is to wait
for a write to the communications register. Any write or
read operation on the MAX1415/MAX1416 is a two-step
process. First, a command byte is written to the communications register. This command selects the input
channel, the desired register for the next read or write
operation, and whether the next operation is a read or a
write. The second step is to read from or write to the
selected register. At the end of the data-transfer cycle,
the device returns to the default state. See the
Performing a Conversion section for examples.
If the serial communication is lost, write 32 ones to the serial interface to return the MAX1415/MAX1416 to the default
state. The registers are not reset after this operation.
24
0/DRDY: (Default = 0) Communication-Start/Data-Ready
Bit. Write a 0 to the 0/DRDY bit to start a write operation to
the communications register. If 0/DRDY = 1, then the
device waits until a 0 is written to 0/DRDY before continuing to load the remaining bits. For a read operation, the
0/DRDY bit shows the status of the conversion. The
DRDY bit returns a 0 if the conversion is complete and
the data is ready. DRDY returns a 1 if the new data has
been read and the next conversion is not yet complete. It
has the same value as the DRDY output pin.
RS2, RS1, RS0: (Default = 0, 0, 0) Register-Select Bits.
RS2, RS1, and RS0 select the next register to be
accessed as shown in Table 7.
R/W: (Default = 0) Read-/Write-Select Bit. Use this bit to
select if the next register access is a read or a write
operation. Set R/W = 0 to select a write operation, or set
R/W = 1 for a read operation on the selected register.
PD: (Default = 0) Power-Down Control Bit. Set PD = 1
to initiate power-down mode. Set PD = 0 to take the
device out of power-down mode. If the internal oscillator or external crystal/resonator is used and CLKDIS =
0, CLKOUT remains active during power-down mode to
provide a clock source for other devices in the system.
CH1, CH0: (Default = 0, 0) Channel-Select Bit. Write to
the CH1 and CH0 bits to select the conversion channel or
to access the calibration data shown in Table 8. The calibration coefficients of a particular channel are stored in
one of the three offset and gain register pairs in Table 8.
Set CH1 = 1 and CH0 = 0 to evaluate the noise performance of the part without external noise sources. In this
noise-evaluation mode, connect AIN1- to an external voltage within the allowable common-mode range.
Setup Register
The byte-wide setup register is bidirectional so it can
be written and read. The byte written to the setup register sets the calibration modes, PGA gain, unipolar/bipolar mode, buffer enable, and conversion start (see
Table 9).
MD1, MD0: (Default = 0, 0) Mode-Select Bits. See
Table 10 for normal operating mode, self-calibration,
zero-scale calibration, or full-scale calibration-mode
selection.
______________________________________________________________________________________
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
(MSB)
FUNCTION
(LSB)
COMMUNICATION
START/DATA READY
Name
REGISTER SELECT
READ/WRITE
SELECT
POWER-DOWN
MODE
CHANNEL SELECT
0/DRDY
RS2
RS1
RS0
R/W
PD
CH1
CH0
0
0
0
0
0
0
0
0
Defaults
Table 7. Register Selection
REGISTER SIZE
(bits)
RS2
RS1
RS0
REGISTER
POWER-ON RESET STATUS
0
0
0
Communications register
0x00
8
0
0
1
Setup register
0x01
8
0
1
0
Clock register
0x85
8
0
1
1
Data register
N/A
16
1
0
0
Test register*
N/A
8
1
0
1
No operation
—
—
1
1
0
Offset register
0x1F 40 00
24
1
1
1
Gain register
0x57 61 AB
24
*The test register is used for factory testing only.
Table 8. Channel Selection
CH1
CH0
AIN+
AIN-
OFFSET/GAIN
REGISTER PAIR
0
0
AIN1+
AIN1-
0
0
1
AIN2+
AIN2-
1
1
0
AIN1-
AIN1-
0
1
1
AIN1-
AIN2-
2
Table 9. Setup Register
(MSB)
FUNCTION
Name
Defaults
(LSB)
MODE CONTROL
PGA GAIN CONTROL
BIPOLAR/UNIPOLAR
MODE
BUFFER ENABLE
FSYNC
MD1
MD0
G2
G1
G0
B/U
BUF
FSYNC
0
0
0
0
0
0
0
1
G2, G1, G0: (Default = 0, 0, 0) Gain-Selection Bits. See
Table 11 for PGA gain settings.
B/U: (Default = 0) Bipolar-/Unipolar-Mode Selection:
Set B/U = 0 to select bipolar mode. Set B/U = 1 to
select unipolar mode.
BUF: (Default = 0) Buffer-Enable Bit. For unbuffered
mode, disable the internal buffer of the MAX1415/
MAX1416 to reduce power consumption by writing a 0 to
the BUF bit. Write a 1 to this bit to enable the buffer. Use
the internal buffer when acquiring high source-impedance input signals.
FSYNC: (Default = 1) Filter-Synchronization/
Conversion-Start Bit. Set FSYNC = 0 to begin calibration
or conversion. The MAX1415/MAX1416 perform free-running conversions while FSYNC = 0. Set FSYNC = 1 to
stop converting data and to hold the nodes of the digital
filter, the filter-control logic, the calibration-control logic,
and the analog modulator in a reset state. The DRDY
output does not reset high if it is low (indicating that valid
data has not yet been read from the data register) when
FSYNC goes high. To clear DRDY output, read the data
register.
______________________________________________________________________________________
25
MAX1415/MAX1416
Table 6. Communications Register
MAX1415/MAX1416
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
Table 10. Operating-Mode Selection
MD1
MD0
0
0
Normal Mode. Use this mode to perform normal conversions on the selected analog input channel.
1
Self-Calibration Mode. This mode performs self-calibration on the selected channel determined from CH0 and
CH1 selection bits in the communications register (Table 6). Upon completion of self-calibration, the device
returns to normal mode with MD1, MD0 returning to 0, 0. The DRDY output bit goes high when self-calibration is
requested and returns low when the calibration is complete and a new data word is in the data register. Selfcalibration performs an internal zero-scale and full-scale calibration. The analog inputs of the device are shorted
together internally during zero-scale calibration and connected to an internally generated (VREF/GAIN) voltage
during full-scale calibration. The offset and gain registers for the selected channel are automatically updated
with the calibration data.
0
Zero-Scale System-Calibration Mode. This mode performs zero-scale calibration on the selected channel
determined from CH1 and CH0 selection bits in the communications register (Table 6). The DRDY output bit
goes high when calibration is requested and returns low when the calibration is complete and a new data word
is in the data register. Performing zero-scale calibration compensates for any DC offset voltage present in the
ADC and system. Ensure that the analog input voltage is stable within 0.5 LSB for the duration of the calibration
sequence. The offset register for the selected channel is updated with the zero-scale system-calibration data.
Upon completion of calibration, the device returns to normal mode with MD1, MD0 returning to 0, 0.
1
Full-Scale System-Calibration Mode. This mode performs full-scale system-calibration on the selected channel
determined from CH1 and CH0 selection bits in the communications register. This calibration assigns a fullscale output code to the voltage present on the selected channel. Ensure that the analog input voltage is stable
within 0.5 LSB for the duration of the calibration sequence. The DRDY output bit goes high during calibration
and returns low when the calibration is complete and a new data word is in the data register. The gain register
for the selected channel is updated with the full-scale system-calibration data. Upon completion of calibration,
the device returns to normal mode with MD1, MD0 returning to 0, 0.
0
1
1
OPERATING MODE
Table 11. PGA Gain Selection
G2
G1
G0
PGA GAIN
0
0
0
1
0
0
1
2
0
1
0
4
0
1
1
8
1
0
0
16
1
0
1
32
1
1
0
64
1
1
1
128
Clock Register
The byte-wide clock register is bidirectional, so it can
be written and read. The byte written to the setup register sets the clock, filter first notch frequency, and the
output data rate (see Table 12).
MXID: (Default = 1) Maxim-Identifier Bit. This is a readonly bit. Values written to this bit are ignored.
ZERO: (Default = 0) Zero Bit. This is a read-only bit.
Values written to this bit are ignored.
26
INTCLK: (Default = 0) Internal Oscillator Bit. Set INTCLK
= 1 to enable the internal oscillator. Set INTCLK = 0 to
disable the internal oscillator.
CLKDIS: (Default = 0) Clock-Disable Bit. Set CLKDIS = 1
to disable the internally or externally generated clock from
appearing on CLKOUT. When using a crystal or resonator across CLKIN and CLKOUT, the clock is stopped
and no conversions take place when CLKDIS = 1.
CLKOUT is held low during clock disable to save power.
Set CLKDIS = 0 to allow other devices to use the output
signal on CLKOUT as a clock source and/or to enable the
external oscillator. The CLKOUT pin on the MAX1415/
MAX1416 can drive one CMOS load.
CLKDIV: (Default = 0) Clock-Divider Control Bit. The
MAX1415/MAX1416 each have an internal clock divider.
Set this bit to 1 to divide the input clock by two. When this
bit is set to 0, the MAX1415/MAX1416 operate at the
internal or external oscillator frequency. CLKDIV has no
effect on the internal oscillator.
CLK: (Default = 1) Clock Bit. When using the internal
oscillator (INTCLK = 1), set CLK = 1 for a frequency of
2.4576MHz, and set CLK = 0 for a frequency of 1MHz.
When using an external clock/oscillator, set CLK = 1 for
f CLKIN = 2.4576MHz with CLKDIV = 0, or f CLKIN =
4.9152MHz with CLKDIV = 1.
______________________________________________________________________________________
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
FS1, FS0: (Default = 0, 1) Filter-Selection Bits. These bits,
in addition to the CLK bit, determine the output data rate
and the digital filter cutoff frequency. See Table 13 for
FS1 and FS0 settings. Recalibrate when the filter characteristics are changed.
Offset and Gain-Calibration Registers
The MAX1415/MAX1416 contain one offset register and
one gain register for each input channel. Each register
is 24 bits wide and can be written and read. The offset
registers store the calibration coefficients resulting from
a zero-scale calibration, and the gain registers store
the calibration coefficients resulting from a full-scale
calibration. The data stored in these registers are 24-bit
straight binary values representing the offset or gain
errors associated with the selected channel. A 24-bit
read or write operation can be performed on the calibration registers for any selected channel. During a
write operation, 24 bits of data must be written to the
register, or no data is transferred.
Data Register
The data register is a 16-bit read-only register. Figure 9
shows how to read conversion results using the
data register.
The data from the data register is read through DOUT.
DOUT changes on the falling edge of SCLK and is valid
on the rising edge of SCLK. The data-register format is
16-bit straight binary for unipolar mode with zero scale
equal to 0x0000, and offset binary for bipolar mode
with zero scale equal to 0x1000.
Table 12. Clock Register
(MSB)
FUNCTION
(LSB)
RESERVED
Name
Defaults
INTERNAL
CLOCK ENABLE
CLOCK
DISABLE
CLOCK
DIVIDER
CLOCK
SELECT
FILTER SELECT
MXID
ZERO
INTCLK
CLKDIS
CLKDIV
CLK
FS1
FS0
1
0
0
0
0
1
0
1
Table 13. Output Data Rate and Notch Frequency vs. Filter Select and CLKIN Frequency
CLKIN FREQUENCY
fCLKIN (MHz)*
CLK
FS1
FS0
OUTPUT DATA RATE
(FIRST NOTCH) (Hz)
-3dB FILTER CUTOFF**
(Hz)
1
0
0
0
20
5.24
1
0
0
1
25
6.55
1
0
1
0
100
26.2
1
0
1
1
200
52.4
2.4576
1
0
0
50
13.1
2.4576
1
0
1
60
15.7
2.4576
1
1
0
250
65.5
2.4576
1
1
1
500
131
*These values are given for CLKDIV = 0. External-clock frequency, fCLKIN, equals two times the values in this column if CLKDIV = 1.
**The filter -3dB filter cutoff frequency = 0.262 x filter first notch frequency.
______________________________________________________________________________________
27
MAX1415/MAX1416
Test Register
This register is reserved for factory testing of the
device. For proper operation of the MAX1415/
MAX1416, do not change this register from its default
power-on reset values.
Set CLK = 0 if the external clock frequency is 1MHz
with CLKDIV = 0 or 2MHz with CLKDIV = 1.
MAX1415/MAX1416
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
Write to the calibration registers in normal mode only.
After writing to the calibration registers, the devices
implement the new offset and gain-register calibration
coefficients at the beginning of a new acquisition. To
ensure the results are valid, discard the first conversion
result after writing to the calibration registers.
To ensure that a conversion is not made using invalid
calibration data, drive FSYNC high prior to writing to the
calibration registers, and then release FSYNC low to initiate conversion.
Table 14. Filter Select and Decimation
Rate
CLK
FS1
FS0
DECIMATION RATE
0
0
0
391
0
0
1
313
0
1
0
78
0
1
1
39
1
0
0
384
Power-On Reset
1
0
1
320
At power-up, the serial interface, logic, digital filter, and
modulator circuits are reset. The registers are set to their
default values. The device returns to wait for a write to
the communications register. For accurate measurements, perform calibration routines after power-up. Allow
time for the external reference and internal or external
oscillator to start up before starting calibration. See the
Typical Operating Characteristics for typical internal and
external oscillator startup times.
1
1
0
77
1
1
1
38
Output data rate =
fCLKIN
128 × Decimation Rate
(if CLKDIV = 0).
Note: First notch filter frequency = output data rate.
Reset
Performing a Conversion
Drive RESET low to reset the MAX1415/MAX1416 to
power-on reset status. DRDY goes high and all communication to the MAX1415/MAX1416 is ignored while RESET
is low. Upon releasing RESET, the device must be reconfigured to begin a conversion. The device returns to waiting for a write to the communication register after a reset
has been performed. Perform a calibration sequence following a reset for accurate conversions.
At power-on reset, the MAX1415/MAX1416 expect a
write to the communications register. Writing to the
communications register selects the acquisition channel, read/write operation for the next register, powerdown/normal mode, and the address of the following
register to be accessed. The MAX1415/MAX1416 have
six user-accessible registers, which control the function
of the device and allow the result to be read. Write to
the communications register before accessing any
other registers.
When using an external clock or crystal oscillator, the
MAX1415/MAX1416 clock generator continues to run
when RESET is pulled low. This allows any device running from CLKOUT to be uninterrupted when the device
is in reset while using an external clock.
Selecting Custom Output Data Rates and
First Notch Frequency
The recommended frequency range of the external
clock is 400kHz to 2.5MHz (clkdw = 0). The output data
rate and first notch frequency are dependent on the
decimation rate of the digital filter. Table 14 shows the
available decimation rates of the digital filter. The output data rate and filter first notch is calculated using the
following formula:
Output data rate =
(if CLKDIV = 1).
28
fCLKIN
× 0.5
128 × Decimation Rate
Writing to the clock and setup registers after configuring
and initializing the host processor serial port sets up the
MAX1415/MAX1416. Use self- or system calibrations to
minimize offset and gain errors (see the Calibration section for more details). Set FSYNC = 0 to begin calibration
or conversion. The MAX1415/MAX1416 perform free-running acquisitions when FSYNC is low (see the Using
FSYNC section). The µC can poll the DRDY bit of the
communications register and read the data register
when the DRDY bit returns a 0. For hardware polling, the
DRDY output goes low when the new data is valid in the
data register.
The data register can be read multiple times while the
next conversion takes place.
The flow diagram in Figure 11 shows an example
sequence required to perform a conversion on channel
1 (AIN1+/AIN1-) after a power-on reset.
______________________________________________________________________________________
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
MAX1415/MAX1416
POWER-ON RESET
INITIALIZE µC/µP SERIAL
PORT
WRITE TO THE COMMUNICATIONS
REGISTER. SELECT CHANNEL 1 AND SET
NEXT OPERATION AS A WRITE TO THE
CLOCK REGISTER
(0x20)
WRITE TO THE CLOCK REGISTER. ENABLE
INTERNAL CLOCK. SET CLOCK FREQUENCY
TO 2.4576MHz. SELECT OUTPUT UPDATE
RATE OF 60Hz.
(0xA5)
WRITE TO THE COMMUNICATIONS
REGISTER. SET NEXT OPERATION AS
A WRITE TO THE SETUP REGISTER.
(0x10)
WRITE TO THE SETUP REGISTER. SET
SELF-CALIBRATION MODE, GAIN TO 0,
UNIPOLAR MODE, UNBUFFERED MODE.
BEGIN SELF-CALIBRATION/CONVERSION
BY CLEARING FSYNC.
(0x44)
HARDWARE POLLING
SOFTWARE POLLING
WRITE TO COMMUNICATIONS REGISTER.
SET NEXT OPERATION AS A READ FROM
THE COMMUNICATIONS REGISTER.
(0x08)
1 (DATA
NOT
READY)
POLL DRDY
OUTPUT
READ THE COMMUNICATIONS REGISTER
(8 BITS)
POLL DRDY
BIT
0 (DATA
READY)
WRITE TO THE COMMUNICATIONS
REGISTER. SET NEXT OPERATION AS A
READ FROM THE DATA REGISTER.
(0x38)
0 (DATA
READY)
1 (DATA NOT
READY)
READ THE DATA REGISTER
(16 BITS)
Figure 11. Sample Flow Diagram for Data Conversion
______________________________________________________________________________________
29
MAX1415/MAX1416
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
Using FSYNC
When FSYNC = 1, the digital filter and analog modulator are in a reset state, inhibiting normal operation. Set
FSYNC = 0 to begin calibration or conversion.
When configured for normal operation (MD1 and MD0
set to 0), DRDY goes low 3 x 1/output data rate after
FSYNC goes low to indicate that the new conversion
result is ready to be read from the data register. DRDY
returns high when a read operation on the data register
is complete. As long as FSYNC remains low, the
MAX1415/MAX1416 perform free-running conversions
with the data registers updating at the output data rate.
If the valid data is not read before the next conversion
result is ready, DRDY returns high for 500 x 1/fCLKIN
before going low again to indicate a new conversion.
Set FSYNC = 1 to stop converting data.
If FSYNC goes high while DRDY is low (indicating that
valid data has not yet been read from the data register), DRDY does not reset high. DRDY remains low until
the new data is read from the data register or until
FSYNC goes low to begin a new conversion.
Table 15 provides the duration-to-mode bits and duration to DRDY for each calibration sequence. Duration-tomode bits provide the time required for the calibration
sequence to complete (MD1 and MD0 return to 0).
Duration to DRDY provides the time until the first conversion result is valid in the data register (DRDY goes low).
The pipeline delay necessary to ensure that the first
conversion result is valid is tP (tP = 2000 x 1/fCLKIN).
When selecting self-calibration (MD1 = 0, MD0 = 1),
DRDY goes low 9 x 1/output data rate + tP after FSYNC
goes low (or after a write operation to the setup register
with MD1 = 0 and MD0 = 1 is performed while FSYNC
is already low) to indicate new data in the data register.
When zero-scale or full-scale calibration is selected,
DRDY goes low 4 x 1/output data rate + tP after FSYNC
goes low (or while the zero-scale or full-scale calibration command is issued when FSYNC is already low) to
indicate new data in the data register (see the
Calibration section).
Calibration
To compensate for errors introduced by temperature
variations or system DC offsets, perform an on-chip calibration. Select calibration options by writing to the
MD1 and MD0 bits in the setup register (Table 9).
Calibration removes gain and offset errors from the
device and/or the system. Recalibrate with changes in
ambient temperature, supply voltage, bipolar/unipolar
mode, buffered/unbuffered mode, PGA gain, and output data rate.
The MAX1415/MAX1416 offer two calibration modes,
self-calibration and system calibration. The channels of
the MAX1415/MAX1416 are independently calibrated
(see Table 8). The calibration coefficients resulting from
a calibration sequence on a selected channel are stored
in the corresponding offset and gain register pair.
Self- and system calibration automatically calculate the
offset and gain coefficients, which are written to the offset and gain registers. These offset and gain coefficients provide offset and gain error correction for the
specified channel.
Self-Calibration
Self-calibration compensates for offset and gain errors
internal to the ADC. Prior to calibration, set the PGA gain,
unipolar/bipolar mode, buffered/unbuffered mode, and
input channel setting. During self-calibration, AIN+ and
AIN- of the selected channel are internally shorted
together. The ADC calibrates this condition as the zeroscale output level. For bipolar mode, this zero-scale
point is the midscale of the bipolar transfer function.
Table 15. Calibration Sequences
CALIBRATION TYPE
(MD1, MD0)
CALIBRATION SEQUENCE
DURATION-TO-MODE
BITS*
DURATION TO DRDY**
Self-calibration (0,1)
Internal zero-scale calibration at
selected gain plus internal fullscale calibration at selected gain
6 x 1/output data rate
9 x 1/output data rate + tP
Zero-scale system calibration (1,0)
Zero-scale calibration on AIN at
selected gain
3 x 1/output data rate
4 x 1/output data rate + tP
Full-scale system calibration (1,1)
Full-scale calibration on AIN at
selected gain
3 x 1/output data rate
4 x 1/output data rate + tP
*Duration-to-mode bits represents the completion of the calibration sequence.
**Duration to DRDY represents the time at which a new conversion result is available in the data register.
30
______________________________________________________________________________________
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
The DRDY output goes high at the start of calibration
and falls low when the calibration is complete and the
next conversion result is valid in the data register. The
total time for self-calibration and one conversion (time
until DRDY goes low) is 9 x 1/output data rate. If DRDY
is low before or goes low during the calibration command write to the setup register, DRDY takes up to one
additional modulator cycle (128/fCLKIN) to return high to
indicate a calibration or conversion in progress.
System Calibration
System calibration compensates for offset and gain
errors for the entire analog signal path including the
ADC, signal conditioning, and signal source. System
calibration is a two-step process and requires individual zero-scale and full-scale calibrations on the selected channel at a specified PGA gain. Recalibration is
recommended with changes in ambient temperature,
supply voltage, buffered/unbuffered mode, bipolar/
unipolar mode, PGA gain, and output data rate.
Set the zero-scale reference point across AIN+ and AIN-.
Start the zero-scale calibration by setting MD1 = 1, MD0
= 0, and FSYNC = 0 in the setup register. When zeroscale calibration is complete (3 x 1/output data rate),
MD1 and MD0 both return to 0. DRDY goes high at the
start of the zero-scale system calibration and returns low
when there is a valid word in the data register (4 x 1/output data rate). The time until DRDY goes low is comprised of one zero-scale calibration sequence (3 x
1/output data rate) and one conversion on the AIN voltage (1 x 1/output data rate). If DRDY is low before or
goes low during the calibration command write to the
setup register, DRDY takes up to one additional modulator cycle (128/fCLKIN) to return high to indicate a calibration or conversion in progress.
After performing a zero-scale calibration, connect the
analog inputs to the full-scale voltage level
(VREF/GAIN). Perform a full-scale calibration by setting
MD1 = 1 and MD0 = 1. After 3 x 1/output data rate,
MD1 and MD0 both return to 0 at the completion of fullscale calibration. DRDY goes high at the beginning of
calibration and returns low after calibration is complete
and new data is in the data register (4 x 1/output data
rate). The time until DRDY goes low is comprised of
one full-scale calibration sequence (3 x 1/output data
rate) and one conversion on the AIN voltage (1 x 1/output data rate). If DRDY is low before or goes low during
the calibration command write to the setup register,
DRDY takes up to one additional modulator cycle
(128/fCLKIN) to return high to indicate a calibration or
conversion in progress.
In bipolar mode, the midpoint (zero scale) and positive
full scale of the transfer function are used to calculate the
calibration coefficients of the gain and offset registers. In
unipolar mode, system calibration is performed using the
two endpoints of the transfer function (Figures 4 and 5).
Power-Down Modes
The MAX1415/MAX1416 include a power-down mode to
save power. Select power-down mode by setting PD = 1
in the communications register. The PD bit does not
affect the serial interface or the status of the DRDY line.
While in power-down mode, the MAX1415/MAX1416
retain the contents of all of its registers. Placing the part
in power-down mode reduces current consumption to
2µA (typ) when in external CMOS clock mode and with
CLKIN connected to VDD or GND. If DRDY is high before
the part enters power-down mode, then DRDY remains
high until the part returns to normal operation mode and
new data is available in the data register. If DRDY is low
before the part enters power-down mode, indicating new
data in the data register, the data register can be read
during power-down mode. DRDY goes high at the end of
this read operation. If the new data remains unread,
DRDY stays low until the MAX1415/MAX1416 are taken
out of power-down mode and resume data conversion.
Resume normal operation by setting PD = 0. The device
begins a new conversion with a result appearing in 3 x
1/output data rate + tP, where tP = 2000 x 1/fCLKIN, after
PD is set to 0. If the clock is stopped during power-down
mode, allow sufficient time for the clock to startup before
resuming conversion.
If the external crystal/resonator is used and CLKDIS =
0, CLKOUT remains active during power-down mode to
provide a clock source for other devices in the system.
If the internal oscillator is used, power-down mode
shuts off the internal oscillator.
______________________________________________________________________________________
31
MAX1415/MAX1416
Next, an internally generated voltage (VREF/GAIN) is
applied across AIN+ and AIN-. This condition results in
the full-scale calibration.
Start self-calibration by setting MD1 = 0, MD0 = 1, and
FSYNC = 0 in the setup register. Self-calibration completes in 6 x 1/output data rate. The MD1 and MD0 bits
both return to 0 at the end of calibration. The device
returns to normal acquisition mode and performs a conversion, which completes in 3 x 1/output data rate after
the self-calibration sequence.
MAX1415/MAX1416
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
Applications Information
VDD
Applications Examples
Strain-Gauge Measurement
Connect the differential inputs of the MAX1415/
MAX1416 to the bridge network of the strain gauge. In
Figure 12, the analog positive supply voltage powers the
bridge network and the MAX1415/MAX1416 along with
the reference voltage in a ratiometric configuration. The
on-chip PGA allows the MAX1415/MAX1416 to handle an
analog input voltage range as low as 20mV to full scale.
Optical Isolation
For applications that require an optically isolated interface, see Figure 13. With 6N136-type optocouplers, the
maximum clock speed is 4MHz. The maximum clock
speed is limited by the degree of mismatch between
the individual optocouplers. Faster optocouplers allow
faster signaling at a higher cost.
Layout, Grounding, and Bypassing
Use PC boards with separate analog and digital
ground planes. Connect the two ground planes together at the MAX1415/MAX1416 GND. Isolate the digital
supply from the analog with a low-value resistor (10Ω)
or ferrite bead when the analog and digital supplies
come from the same source.
Ensure that digital return currents do not pass through
the analog ground and that return-current paths are low
impedance. A 5mA current flowing through a PC board
ground trace impedance of only 0.05Ω creates an error
voltage of approximately 250µV.
Layout the PC board to ensure digital and analog signal
lines are kept separate. Do not run digital lines (especially the SCLK and DOUT) parallel to any analog lines. If
they must cross one another, do so at right angles.
Bypass VDD to the analog ground plane with a 0.1µF
capacitor in parallel with a 1µF to 10µF low-ESR capacitor. Keep capacitor leads short for best supply-noise
rejection. Bypass REF+, REF-, and all analog inputs
with a 0.1µF capacitor to GND. Place all bypass capacitors as close to the device as possible to achieve the
best decoupling.
Definitions
Integral Nonlinearity
Integral nonlinearity (INL) is the deviation of the values
on an actual transfer function from a straight line. This
straight line is either a best-straight-line fit or a line
drawn between the endpoints of the transfer function,
once offset and gain errors have been nullified. INL for
the MAX1415/MAX1416 is measured using the endpoint method. This is the more conservative method.
32
10µF
0.1µF
REF+
RREF
VDD
CLKIN
0.1µF
CLKOUT
REF0.1µF
ACTIVE
GAUGE
CS
MAX1415
MAX1416
R
SCLK
DIN
AIN1+
0.1µF
DOUT
DRDY
AIN1-
DUMMY
GAUGE
R
RESET
0.1µF
GND
Figure 12. Strain Gauge Measurement
Unipolar Offset Error
For an ideal converter, the first transition occurs at 0.5
LSB above zero. Offset error is the amount of deviation
between the measured first transition point and the
ideal point.
Bipolar Zero Error
In bipolar mode, the ideal midscale transition occurs at
AIN+ - AIN- = 0. Bipolar zero error is the measured
deviation from this ideal value.
Gain Error
With a full-scale analog input voltage applied to the
ADC (resulting in all ones in the digital code), gain error
is defined as the amount of deviation between the ideal
transfer function and the measured transfer function
(with the offset error or bipolar zero error removed).
Gain error is usually expressed in LSB or a percent of
full-scale range (%FSR).
Positive Full-Scale Error
For the ideal transfer curve, the code edge transition
that causes a full-scale transition to occur is 1.5 LSB
below full scale. The positive full-scale error is the difference between this code transition of the ideal trans-
______________________________________________________________________________________
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
ISO
3V/5V
+VCC
VDD
2kΩ
VCC
Bipolar Negative Full-Scale Error
For the ideal transfer curve, the code edge transition that
causes a negative full-scale transition to occur is 0.5 LSB
above negative full scale. The negative full-scale error is
the difference between the ideal value at this code transition and the actual measured value at this code transition.
DIN
6N136
100Ω
MOSI
MAX1415
MAX1416
2kΩ
VCC
Input Common-Mode Rejection
Input common-mode rejection is the ability of a device
to reject a signal that is common to or applied to both
input terminals. The common-mode signal can be
either an AC or a DC signal or a combination of the two.
CMR is often expressed in decibels. Common-mode
rejection ratio (CMRR) is the ratio of the differential signal gain to the common-mode signal gain.
MAX1415/MAX1416
fer function and the actual measured value at this code
transition. Unlike gain error, unipolar offset error and
bipolar zero error are included in the positive full-scale
error measurement.
SCLK
6N136
100Ω
SCK
VCC
2kΩ
MISO
6N136
Power-Supply Rejection Ratio
Power-supply rejection ratio (PSRR) is the ratio of the
input signal change (V) to the change in the converter
output (V). It is typically measured in decibels.
DOUT
100Ω
CS
Figure 13. Optically Isolated Interface
Ordering Information (continued)
PART
TEMP
RANGE
PINPACKAGE
VDD
(V)
PKG
CODE
MAX1416ENE*
-45°C to +85°C 16 PDIP
5
P16-1
MAX1416EWE*
-45°C to +85°C 16 Wide SO
5
W16-1
MAX1416EUE
-45°C to +85°C 16 TSSOP
5
U16-1
MAX1416AENE* -45°C to +85°C 16 PDIP
5
P16-1
MAX1416AEWE* -45°C to +85°C 16 Wide SO
5
W16-1
MAX1416AEUE* -45°C to +85°C 16 TSSOP
5
U16-1
MAX1416CNE*
5
P16-1
0°C to +70°C 16 PDIP
MAX1416CWE*
0°C to +70°C 16 Wide SO
5
W16-1
MAX1416CUE*
0°C to +70°C 16 TSSOP
5
U16-1
Chip Information
TRANSISTOR COUNT: 42,000
PROCESS: BiCMOS
*Future product—contact factory for availability.
______________________________________________________________________________________
33
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
PDIPN.EPS
MAX1415/MAX1416
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
34
______________________________________________________________________________________
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
E
DIM
A
A1
B
C
e
E
H
L
H
MAX
MIN
0.104
0.093
0.012
0.004
0.019
0.014
0.013
0.009
0.050
0.299
0.291
0.394
0.419
0.050
0.016
SOICW.EPS
INCHES
N
MILLIMETERS
MIN
2.35
0.10
0.35
0.23
MAX
2.65
0.30
0.49
0.32
1.27
7.40
7.60
10.00
10.65
0.40
1.27
VARIATIONS:
1
INCHES
TOP VIEW
DIM
D
D
D
D
D
D
A
B
e
FRONT VIEW
MIN
0.398
0.447
0.496
0.598
0.697
MAX
0.413
0.463
0.512
0.614
0.713
MILLIMETERS
MIN
10.10
11.35
12.60
15.20
17.70
MAX
10.50
11.75
13.00
15.60
18.10
N MS013
16
AA
18
AB
20 AC
24 AD
28 AE
C
0∞-8∞
A1
L
SIDE VIEW
PROPRIETARY INFORMATION
TITLE:
PACKAGE OUTLINE, .300" SOIC
APPROVAL
DOCUMENT CONTROL NO.
21-0042
REV.
B
1
______________________________________________________________________________________
1
35
MAX1415/MAX1416
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
TSSOP4.40mm.EPS
MAX1415/MAX1416
16-Bit, Low-Power, 2-Channel,
Sigma-Delta ADCs
PACKAGE OUTLINE, TSSOP 4.40mm BODY
21-0066
G
1
1
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