LTC1403-1/LTC1403A-1
Serial 12-Bit/14-Bit, 2.8Msps
Sampling ADCs with Shutdown
FEATURES
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s
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DESCRIPTIO
2.8Msps Conversion Rate
Low Power Dissipation: 14mW
3V Single Supply Operation
2.5V Internal Bandgap Reference can be Overdriven
3-Wire Serial Interface
Sleep (10µW) Shutdown Mode
Nap (3mW) Shutdown Mode
80dB Common Mode Rejection
±1.25V
Bipolar Input Range
Tiny 10-Lead MSE Package
The LTC
®
1403-1/LTC1403A-1 are 12-bit/14-bit, 2.8Msps
serial ADCs with differential inputs. The devices draw only
4.7mA from a single 3V supply and come in a tiny 10-lead
MSE package. A Sleep shutdown feature lowers power
consumption to 10µW. The combination of speed, low
power and tiny package makes the LTC1403-1/LTC1403A-1
suitable for high speed, portable applications.
The 80dB common mode rejection allows users to elimi-
nate ground loops and common mode noise by measuring
signals differentially from the source.
The devices convert –1.25V to 1.25V bipolar inputs differ-
entially. The absolute voltage swing for +A
IN
and
–A
IN
extends from ground to the supply voltage.
The serial interface sends out the conversion results
during the 16 clock cycles following CONV↑ for compat-
ibility with standard serial interfaces. If two additional
clock cycles for acquisition time are allowed after the data
stream in between conversions, the full sampling rate of
2.8Msps can be achieved with a 50.4MHz clock.
, LTC and LT are registered trademarks of Linear Technology Corporation.
APPLICATIO S
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Communications
Data Acquisition Systems
Uninterrupted Power Supplies
Multiphase Motor Control
Multiplexed Data Acquisition
BLOCK DIAGRA
10µF
3V
LTC1403A-1
A
IN+
A
IN–
1
7
V
DD
14-BIT LATCH
THREE-
STATE
SERIAL
OUTPUT
PORT
14
+
S&H
14-BIT ADC
THD, 2nd, 3rd (dB)
8
SDO
2
–
V
REF
2.5V
REFERENCE
3
10µF
4
10
TIMING
LOGIC
9
6
11
EXPOSED PAD
CONV
GND
5
SCK
14031 BD
U
THD, 2nd and 3rd vs Input
Frequency for Differential Input
Signals
–44
–50
–56
–62
–68
–74
–80
–86
–92
–98
–104
0.1
1
10
FREQUENCY (MHz)
100
14031 G19
W
U
THD
3rd
2nd
14031f
1
LTC1403-1/LTC1403A-1
ABSOLUTE
(Notes 1, 2)
AXI U
RATI GS
PACKAGE/ORDER I FOR ATIO
ORDER PART
NUMBER
TOP VIEW
A
IN+
1
A
IN–
2
V
REF
3
GND 4
GND 5
10
9
8
7
6
CONV
SCK
SDO
V
DD
GND
Supply Voltage (V
DD
) ................................................. 4V
Analog Input Voltage
(Note 3) ....................................–0.3V to (V
DD
+ 0.3V)
Digital Input Voltage ................... – 0.3V to (V
DD
+ 0.3V)
Digital Output Voltage .................. – 0.3V to (V
DD
+ 0.3V)
Power Dissipation .............................................. 100mW
Operation Temperature Range
LTC1403C-1/LTC1403AC-1 ..................... 0°C to 70°C
LTC1403I-1/LTC1403AI-1 .................. – 40°C to 85°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
11
LTC1403CMSE-1
LTC1403IMSE-1
LTC1403ACMSE-1
LTC1403AIMSE-1
MSE PART MARKING
LTBGP
LTBGQ
LTBGR
LTBGS
MSE PACKAGE
10-LEAD PLASTIC MSOP
T
JMAX
= 125°C,
θ
JA
= 150°C/ W
EXPOSED PAD (PIN 11) IS GND
MUST BE SOLDERED TO PCB
Consult LTC Marketing for parts specified with wider operating temperature ranges.
CO VERTER CHARACTERISTICS
PARAMETER
Resolution (No Missing Codes)
Integral Linearity Error
Offset Error
Gain Error
Gain Tempco
(Notes 4, 5, 18)
(Notes 4, 18)
(Note 4, 18)
CONDITIONS
The
q
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. With internal reference. V
DD
= 3V
LTC1403-1
MIN TYP MAX
q
q
q
q
LTC1403A-1
MIN TYP MAX
14
–4
–20
–60
±0.5
±2
±10
±15
±1
4
20
60
UNITS
Bits
LSB
LSB
LSB
ppm/°C
ppm/°C
12
–2
–10
–30
±0.25
±1
±5
±15
±1
2
10
30
Internal Reference (Note 4)
External Reference
A ALOG I PUT
SYMBOL PARAMETER
V
IN
V
CM
I
IN
C
IN
t
ACQ
t
AP
t
JITTER
CMRR
The
q
denotes the specifications which apply over the full operating temperature range,
otherwise specifications are at T
A
= 25°C. V
DD
= 3V
CONDITIONS
2.7V
≤
V
DD
≤
3.3V
q
MIN
TYP
–1.25 to 1.25
0 to V
DD
MAX
UNITS
V
V
Analog Differential Input Range (Notes 3, 8, 9)
Analog Common Mode + Differential
Input Range (Note 10)
Analog Input Leakage Current
Analog Input Capacitance
Sample-and-Hold Acquisition Time
Sample-and-Hold Aperture Delay Time
Sample-and-Hold Aperture Delay Time Jitter
Analog Input Common Mode Rejection Ratio
q
1
13
39
1
0.3
(Note 6)
q
f
IN
= 1MHz, V
IN
= 0V to 3V
f
IN
= 100MHz, V
IN
= 0V to 3V
–60
–15
2
U
µA
pF
ns
ns
ps
dB
dB
14031f
W
U
U
W W
W
U
U
U
LTC1403-1/LTC1403A-1
DY A IC ACCURACY
SYMBOL
SINAD
PARAMETER
Signal-to-Noise Plus
Distortion Ratio
The
q
denotes the specifications which apply over the full operating temperature range,
otherwise specifications are at T
A
= 25°C. V
DD
= 3V. Single-ended A
IN+
signal drive with A
IN–
= 1.5V DC. Differential signal drive with
V
CM
= 1.5V at A
IN+
and A
IN–
CONDITIONS
100kHz Input Signal (Note 19)
1.4MHz Input Signal (Note 19)
100kHz Input Signal, External V
REF
= 3.3V,
V
DD
≥
3.3V (Note 19)
750kHz Input Signal, External V
REF
= 3.3V,
V
DD
≥
3.3V (Note 19)
100kHz First 5 Harmonics (Note 19)
1.4MHz First 5 Harmonics (Note 19)
100kHz Input Signal (Note 19)
1.4MHz Input Signal (Note 19)
0.625V
P-P
1.4MHz Summed with 0.625V
P-P
1.56MHz into A
IN+
and Inverted into A
IN–
V
REF
= 2.5V (Note 18)
V
IN
= 2.5V
P-P
, SDO = 11585LSB
P-P
(Note 15)
S/(N + D)
≥
68dB
q
THD
SFDR
IMD
I TER AL REFERE CE CHARACTERISTICS
PARAMETER
V
REF
Output Voltage
V
REF
Output Tempco
V
REF
Line Regulation
V
REF
Output Resistance
V
REF
Settling Time
CONDITIONS
I
OUT
= 0
The
q
denotes the specifications which apply over the
full operating temperature range, otherwise specifications are at T
A
= 25°C. V
DD
= 3V
MIN
TYP
2.5
15
V
DD
= 2.7V to 3.6V, V
REF
= 2.5V
Load Current = 0.5mA
600
0.2
2
MAX
UNITS
V
ppm/°C
µV/V
Ω
ms
DIGITAL I PUTS A D DIGITAL OUTPUTS
SYMBOL
V
IH
V
IL
I
IN
C
IN
V
OH
V
OL
I
OZ
C
OZ
I
SOURCE
I
SINK
PARAMETER
High Level Input Voltage
Low Level Input Voltage
Digital Input Current
Digital Input Capacitance
High Level Output Voltage
Low Level Output Voltage
Hi-Z Output Leakage D
OUT
Hi-Z Output Capacitance D
OUT
Output Short-Circuit Source Current
Output Short-Circuit Sink Current
V
OUT
= 0V, V
DD
= 3V
V
OUT
= V
DD
= 3V
CONDITIONS
V
DD
= 3.3V
V
DD
= 2.7V
V
IN
= 0V to V
DD
(Note 20)
The
q
denotes the specifications which apply over the
full operating temperature range, otherwise specifications are at T
A
= 25°C. V
DD
= 3V
MIN
q
q
q
U
U
U
W U
U
MIN
68
LTC1403-1
TYP MAX
70.5
70.5
72
72
–87
–83
–87
–83
–82
0.25
50
5
LTC1403A-1
MIN TYP MAX
70
73.5
73.5
76.3
76.3
–90
–86
–90
–86
–82
1
50
5
UNITS
dB
dB
dB
dB
dB
dB
dB
dB
dB
LSB
RMS
MHz
MHz
Total Harmonic
Distortion
Spurious Free
Dynamic Range
Intermodulation
Distortion
Code-to-Code
Transition Noise
Full Power Bandwidth
Full Linear Bandwidth
q
–76
–78
U
TYP
MAX
0.6
±10
UNITS
V
V
µA
pF
V
V
V
µA
pF
mA
mA
14031f
2.4
5
q
q
q
V
DD
= 3V, I
OUT
= – 200µA
V
DD
= 2.7V, I
OUT
= 160µA
V
DD
= 2.7V, I
OUT
= 1.6mA
V
OUT
= 0V to V
DD
2.5
2.9
0.05
0.10
1
20
15
0.4
±10
3
LTC1403-1/LTC1403A-1
POWER REQUIRE E TS
SYMBOL
V
DD
I
DD
PARAMETER
Supply Voltage
Positive Supply Voltage
The
q
denotes the specifications which apply over the full operating temperature
range, otherwise specifications are at T
A
= 25°C. (Note 17)
CONDITIONS
Active Mode
Nap Mode
Sleep Mode (LTC1403)
Sleep Mode (LTC1403A)
Active Mode with SCK in Fixed State (Hi or Lo)
q
q
P
D
Power Dissipation
The
q
denotes the specifications which apply over the full operating temperature
range, otherwise specifications are at T
A
= 25°C. V
DD
= 3V
SYMBOL
f
SAMPLE(MAX)
t
THROUGHPUT
t
SCK
t
CONV
t
1
t
2
t
3
t
4
t
5
t
6
t
7
t
8
t
9
t
10
t
12
PARAMETER
Maximum Sampling Frequency per Channel
(Conversion Rate)
Minimum Sampling Period (Conversion + Acquisiton Period)
Clock Period
Conversion Time
Minimum Positive or Negative SCLK Pulse Width
CONV to SCK Setup Time
Nearest SCK Edge Before CONV
Minimum Positive or Negative CONV Pulse Width
SCK to Sample Mode
CONV to Hold Mode
16th SCK↑ to CONV↑ Interval (Affects Acquisition Period)
Minimum Delay from SCK to Valid Data
SCK to Hi-Z at SDO
Previous SDO Bit Remains Valid After SCK
V
REF
Settling Time After Sleep-to-Wake Transition
CONDITIONS
q
q
TI I G CHARACTERISTICS
Note 1:
Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2:
All voltage values are with respect to GND.
Note 3:
When these pins are taken below GND or above V
DD
, they will be
clamped by internal diodes. This product can handle input currents greater
than 100mA below GND or greater than V
DD
without latchup.
Note 4:
Offset and full-scale specifications are measured for a single-
ended A
IN+
input with A
IN–
grounded and using the internal 2.5V reference.
Note 5:
Integral linearity is tested with an external 2.55V reference and is
defined as the deviation of a code from the straight line passing through
the actual endpoints of a transfer curve. The deviation is measured from
the center of quantization band.
Note 6:
Guaranteed by design, not subject to test.
Note 7:
Recommended operating conditions.
Note 8:
The analog input range is defined for the voltage difference
between A
IN+
and A
IN–
. Performance is specified with A
IN–
= 1.5V DC while
driving A
IN+
.
Note 9:
The absolute voltage at A
IN+
and A
IN–
must be within this range.
Note 10:
If less than 3ns is allowed, the output data will appear one clock
cycle later. It is best for CONV to rise half a clock before SCK, when
running the clock at rated speed.
4
U W
MIN
2.7
TYP
4.7
1.1
2
2
12
MAX
3.6
7
1.5
15
10
UNITS
V
mA
mA
µA
µA
mW
UW
MIN
2.8
TYP
MAX
UNITS
MHz
ns
ns
SCLK cycles
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ms
(Note 16)
(Note 6)
(Note 6)
(Notes 6, 10)
(Note 6)
(Note 6)
(Note 6)
(Notes 6, 11)
(Notes 6, 7, 13)
(Notes 6, 12)
(Notes 6, 12)
(Notes 6, 12)
(Notes 6, 14)
q
19.8
16
2
3
0
4
4
1.2
45
8
6
2
357
10000
18
2
Note 11:
Not the same as aperture delay. Aperture delay is smaller (1ns)
because the 2.2ns delay through the sample-and-hold is subtracted from
the CONV to Hold mode delay.
Note 12:
The rising edge of SCK is guaranteed to catch the data coming
out into a storage latch.
Note 13:
The time period for acquiring the input signal is started by the
16th rising clock and it is ended by the rising edge of convert.
Note 14:
The internal reference settles in 2ms after it wakes up from Sleep
mode with one or more cycles at SCK and a 10µF capacitive load.
Note 15:
The full power bandwidth is the frequency where the output code
swing drops to 3dB with a 2.5V
P-P
input sine wave.
Note 16:
Maximum clock period guarantees analog performance during
conversion. Output data can be read without an arbitrarily long clock.
Note 17:
V
DD
= 3V, f
SAMPLE
= 2.8Msps.
Note 18:
The LTC1403A-1 is measured and specified with 14-bit
Resolution (1LSB = 152µV) and the LTC1403-1 is measured and specified
with 12-bit Resolution (1LSB = 610µV).
Note 19:
Full-scale sinewaves are fed into the noninverting input while the
inverting input is kept at 1.5V DC.
Note 20:
The sampling capacitor at each input accounts for 4.1pF of the
input capacitance.
14031f
LTC1403-1/LTC1403A-1
with A
IN
TYPICAL PERFOR A CE CHARACTERISTICS
–
ENOBs and SINAD
vs Input Frequency
12.0
11.5
11.0
74
71
68
65
62
59
56
53
1
10
FREQUENCY (MHz)
50
100
14031 G01
T
A
= 25°C, V
DD
= 3V. Single ended A
IN+
signal drive
= 1.5V DC, differential signals drive both inputs with V
CM
= 1.5V DC (LTC1403A-1)
THD, 2nd and 3rd vs Input
Frequency
–44
–50
–56
10.0
9.5
9.0
8.5
8.0
0.1
–74
–80
–86
–92
–98
–104
0.1
THD
3rd
2nd
SFDR (dB)
100
14031 G02
10.5
THD, 2nd, 3rd (dB)
ENOBs (BITS)
SNR vs Input Frequency
74
71
68
12.0
11.5
11.0
SNR (dB)
65
62
59
56
53
50
0.1
1
10
FREQUENCY (MHz)
100
14031 G04
10.5
10.0
9.5
9.0
8.5
8.0
0.1
1
10
FREQUENCY (MHz)
65
62
59
56
53
50
100
14031 G18
THD, 2nd, 3rd (dB)
ENOBs (BITS)
SFDR vs Input Frequency for
Differential Input Signals
104
98
92
MAGNITUDE (dB)
MAGNITUDE (dB)
86
SFDR (dB)
80
74
68
62
56
50
44
0.1
1
10
FREQUENCY (MHz)
100
14031 G20
U W
SFDR vs Input Frequency
104
98
92
86
80
74
68
62
56
50
–62
–68
SINAD (dB)
1
10
FREQUENCY (MHz)
44
0.1
1
10
FREQUENCY (MHz)
100
14031 G03
ENOBs and SINAD vs Input
Frequency for Differential Input
Signals
74
71
68
THD, 2nd and 3rd vs Input
Frequency for Differential Input
Signals
–44
–50
–56
–62
–68
–74
–80
–86
–92
–98
–104
0.1
1
10
FREQUENCY (MHz)
100
14031 G19
SINAD (dB)
THD
3rd
2nd
98kHz Sine Wave 4096 Point
FFT Plot
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
–100
–110
–120
0
350
700k
1.05M
FREQUENCY (Hz)
1.4M
14031 G05
1.3MHz Sine Wave 4096 Point
FFT Plot
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
–100
–110
–120
0
350k
700k
1.05M
FREQUENCY (Hz)
1.4M
14031 G06
14031f
5
