LTC1411
Single Supply
14-Bit 2.5Msps ADC
FEATURES
s
s
s
s
s
s
s
s
s
s
s
DESCRIPTIO
Sample Rate: 2.5Msps
80dB S/(N + D) and 90dB THD at 100kHz f
IN
Single 5V Operation
No Pipeline Delay
Programmable Input Ranges
Low Power Dissipation: 195mW (Typ)
True Differential Inputs Reject Common Mode Noise
Out-of-Range Indicator
Internal or External Reference
Sleep (1µA) and Nap (2mA) Shutdown Modes
36-Pin SSOP Package
The LTC
®
1411 is a 2.5Msps sampling 14-bit A/D con-
verter in a 36-pin SSOP package, which typically dissi-
pates only 195mW from a single 5V supply. This device
comes complete with a high bandwidth sample-and-
hold, a precision reference, programmable input ranges
and an internally trimmed clock. The ADC can be powered
down with either the Nap or Sleep mode for low power
applications.
The LTC1411 converts either differential or single-ended
inputs and presents data in 2’s complement format.
Maximum DC specs include
±2LSB
INL and 14-bit no
missing code over temperature. Outstanding dynamic
performance includes 80dB S/(N + D) and 90dB THD at
100kHz input frequency.
The LTC1411 has four programmable input ranges se-
lected by two digital input pins, PGA0 and PGA1. This
provides input spans of
±1.8V, ±1.27V, ±0.9V
and
±0.64V.
An out-of-the-range signal together with the D13 (MSB)
will indicate whether a signal is over or under the ADC’s
input range. A simple conversion start input and a data
ready signal ease connections to FIFOs, DSPs and micro-
processors.
APPLICATIO S
s
s
s
s
s
s
Telecommunications
High Speed Data Acquisition
Digital Signal Processing
Multiplexed Data Acquisition Systems
Spectrum Analysis
Imaging Systems
, LTC and LT are registered trademarks of Linear Technology Corporation.
BLOCK DIAGRA
1
2
A
IN
+
10
AVP
30
DVP
OV
DD
29
86
80
74
68
62
56
50
44
38
32
26
20
14
10
A
IN–
REFOUT
REFIN
5k
5k
2k
INTERNAL
CLOCK
2.5V
BANDGAP
REFERENCE
OGND 28
D13
3
4
+
–
12
14-BIT
ADC
14
OUTPUT
DRIVERS
D0
BUSY
OTR
25
27
26
5
REFCOM1
REFCOM2
6
X1.62/
X1.15
CONTROL LOGIC
S/(N + D) (dB)
•
•
•
7, 8, 9
AGND
11
AVM
36
SLP
35
NAP
34
PGA0
33
PGA1
32
CONVST
31
DGND
1411 BD
U
S/(N + D) and Effective Bits
vs Input Frequency
14
13
12
11
10
W
U
EFFECTIVE BITS
100
1000
INPUT FREQUENCY (kHz)
10000
1411 TA02
1411f
1
LTC1411
ABSOLUTE
AXI U
RATI GS
PACKAGE/ORDER I FOR ATIO
TOP VIEW
A
IN+
A
IN–
REFOUT
REFIN
REFCOM1
REFCOM2
AGND1
AGND2
AGND3
1
2
3
4
5
6
7
8
9
36 SLP
35 NAP
34 PGA0
33 PGA1
32 CONVST
31 DGND
30 DVP
29 OV
DD
28 OGND
27 BUSY
26 OTR
25 D0
24 D1
23 D2
22 D3
21 D4
20 D5
19 D6
AVP = DVP = OV
DD
= V
DD
(Notes 1, 2)
Supply Voltage (V
DD
) ................................................. 6V
Analog Input Voltage (Note 3) ... – 0.3V to (V
DD
+ 0.3V)
Digital Input Voltage (Note 4) .................. – 0.3V to 10V
Digital Output Voltage ............... – 0.3V to (V
DD
+ 0.3V)
Power Dissipation .............................................. 500mW
Operating Temperature Range
LTC1411C ............................................... 0°C to 70°C
LTC1411I ............................................ – 40°C to 85°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
ORDER PART
NUMBER
LTC1411CG
LTC1411IG
AVP 10
AVM 11
D13 (MSB) 12
D12 13
D11 14
D10 15
D9 16
D8 17
D7 18
G PACKAGE
36-LEAD PLASTIC SSOP
T
JMAX
= 125°C,
θ
JA
= 95°C/ W
Consult LTC Marketing for parts specified with wider operating temperature ranges.
CO VERTER CHARACTERISTICS
PARAMETER
Resolution (No Missing Codes)
Integral Linearity Error
Offset Error
Full-Scale Error
Full-Scale Tempco
(Note 7)
(Note 8)
The
q
denotes specifications which apply over the full operating
temperature range, otherwise specifications are T
A
= 25°C. (Notes 5, 6)
CONDITIONS
q
q
q
MIN
14
TYP
MAX
±2
±16
±24
±
60
UNITS
Bits
LSB
LSB
LSB
LSB
ppm/°C
External Reference = 2.5V
I
OUT(REF)
= 0
±15
DY A IC ACCURACY
SYMBOL PARAMETER
T
A
= 25°C (Note 5)
CONDITIONS
100kHz Input Signal
500kHz Input Signal
100kHz Input Signal, Up to 5th Harmonic
500kHz Input Signal, Up to 5th Harmonic
100kHz Input Signal
500kHz Input Signal
S/(N + D)
≥
74dB
MIN
TYP
80.0
77.5
– 90
– 82
90
82
1.0
0.66
MAX
UNITS
dB
dB
dB
dB
dB
dB
MHz
LSB
RMS
1411f
S/(N + D) Signal-to-Noise Plus Distortion Ratio
THD
Total Harmonic Distortion
Peak Harmonic or Spurious Noise
Full Linear Bandwidth
Transition Noise
2
U
W
U
U
W W
W
W U
U
LTC1411
A ALOG I PUT
SYMBOL PARAMETER
V
IN
Analog Input Range (Note 9)
Common Mode Input Range
C
IN
t
ACQ
t
AP
t
jitter
CMRR
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
Input Leakage Current (Pins 1, 2)
I TER AL REFERE CE CHARACTERISTICS
PARAMETER
V
REF
Output Voltage
V
REF
Output Tempco
V
REF
Line Regulation
V
REF
Load Regulation
REFCOM2 Output Voltage
REFIN Input Current
CONDITIONS
I
OUT
= 0
I
OUT
= 0
4.75V
≤
V
DD
≤
5.25V
0
≤
I
OUT
≤
1mA
DIGITAL I PUTS A D DIGITAL OUTPUTS
The
q
denotes specifications which apply over the full operating temperature range, otherwise specifications are T
A
= 25°C. (Note 5)
SYMBOL PARAMETER
V
IH
V
IL
I
IN
C
IN
V
OH
V
OL
I
SOURCE
I
SINK
High Level Input Voltage
Low Level Input Voltage
Digital Input Current
Digital Input Capacitance
High Level Output Voltage
Low Level Output Voltage
Output Source Current
Output Sink Current
V
DD
= 4.75V, I
O
= – 10µA
V
DD
= 4.75V, I
O
= – 200µA
V
DD
= 4.75V, I
O
= 160µA
V
DD
= 4.75V, I
O
= 1.6mA
V
OUT
= 0V
V
OUT
= V
DD
q
q
POWER REQUIRE E TS
The
q
denotes specifications which apply over the full operating temperature range, otherwise specifications are T
A
= 25°C. (Note 5)
SYMBOL PARAMETER
V
DD
I
DD
Supply Voltage
Supply Current
Nap Mode
Sleep Mode
Power Dissipation
Nap Mode
Sleep Mode
CONDITIONS
(Note 9)
q
P
D
U W
U
U
U
U
U
U
T
A
= 25°C (Note 5)
CONDITIONS
(A
IN+
) – (A
IN–
), PGA0 = PGA1 = 5V
(A
IN+
) – (A
IN–
), PGA0 = 5V, PGA1 = 0V
(A
IN+
) – (A
IN–
), PGA0 = 0V, PGA1 = 5V
(A
IN+
) – (A
IN–
), PGA0 = PGA1 = 0V
A
IN+
or A
IN–
Between Conversions (Sample Mode)
During Conversions (Hold Mode)
MIN
TYP
±1.8
±1.27
±0.9
±0.64
0
10
4
100
7
1
0V < (A
IN–
= A
IN+
) < V
DD
62
0.1
V
DD
MAX
UNITS
V
V
V
V
V
pF
pF
ns
ns
ps
RMS
dB
µA
U
T
A
= 25°C (Note 5)
MIN
2.480
TYP
2.500
±15
0.01
2
4.05
250
MAX
2.520
UNITS
V
ppm/°C
LSB/ V
LSB/mA
V
µA
I
OUT
= 0, PGA0 = PGA1 = 5V
REFIN = External Reference 2.5V
CONDITIONS
V
DD
= 5.25V
V
DD
= 4.75V
V
IN
= 0V to V
DD
, Except SLP, NAP (Note 11)
q
q
q
MIN
2.4
TYP
MAX
0.8
±10
UNITS
V
V
µA
pF
V
V
2
4.75
4.0
0.05
0.10
– 10
10
0.4
V
V
mA
mA
MIN
4.75
TYP
39
2
1
195
10
5
MAX
5.25
65
UNITS
V
mA
mA
µA
mW
mW
µW
1411f
NAP = 0V (Note 11)
SLP = 0V
q
325
NAP = 0V
SLP = 0V
3
LTC1411
TI I G CHARACTERISTICS
SYMBOL
f
SAMPLE(MAX)
t
CONV
t
ACQ
t
0
t
1
t
2
t
3
t
4
t
5
t
6
PARAMETER
Maximum Sampling Frequency
Conversion Time
Acquisition Time
SLP↑ to CONVST↓ Wake-Up Time
NAP↑ to CONVST↓ Wake-Up Time
CONVST Low Time
CONVST to BUSY Delay
Data Ready After BUSY↑
CONVST High Time
Aperture Delay of Sample-and-Hold
The
q
denotes specifications which apply over the full operating temperature
range, otherwise specifications are T
A
= 25°C. (Notes 5) (See Figures 11a, 11b)
CONDITIONS
(Note 9)
q
q
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 ground with DGND, OGND,
AVM and AGND wired together unless otherwise noted.
Note 3:
When these pin voltages are taken below AGND or above V
DD
,
they will be clamped by internal diodes. This product can handle input
currents greater than 100mA without latchup.
Note 4:
When these pin voltages are taken below AGND, they will be
clamped by internal diodes. This product can handle input currents greater
than 100mA below AGND without latchup. These pins are not clamped to
V
DD
.
Note 5:
V
DD
= 5V, PGA1 = PGA0 = 5V, f
SAMPLE
= 2.5MHz at 25°C and
t
r
= t
f
= 5ns unless otherwise specified.
Note 6:
Linearity, offset and full-scale specifications apply for a single-
ended A
IN+
input with A
IN–
tied to an external 2.5V reference voltage.
TYPICAL PERFOR A CE CHARACTERISTICS
S/(N + D) vs Input Frequency
86
80
74
68
62
56
50
44
38
32
26
20
14
10
100
1000
INPUT FREQUENCY (kHz)
10000
1411 G01
S/(N + D) (dB)
62
DISTORTION (dB)
SNR (dB)
4
U W
UW
MIN
2.5
TYP
250
100
210
250
MAX
350
UNITS
MHz
ns
ns
ms
ns
ns
ns
ns
ns
ns
10µF Bypass Capacitor at REFCOM2 Pin
(Note 10)
C
L
= 25pF
(Note 10)
q
q
20
12
7
20
7
Note 7:
Integral nonlinearity is defined as the deviation of a code from a
straight line passing through the actual endpoints of the transfer curve.
The deviation is measured from the center of the quantization band.
Note 8:
Bipolar offset is the offset voltage measured from – 0.5LSB
when the output code flickers between 0000 0000 0000 00 and
1111 1111 1111 11.
Note 9:
Recommended operating conditions.
Note 10:
The falling CONVST edge starts a conversion. If CONVST returns
high at a critical point during the conversion it can create small errors. For
best performance ensure that CONVST returns high within 20ns after
conversion start of after BUSY rises.
Note 11:
SLP and NAP have an internal pull-down so the pins will draw
approximately 7µA when tied high and less than 1µA when tied low.
Signal-to-Noise Ratio
vs Input Frequency
86
80
74
68
56
50
44
38
32
26
20
14
10
100
1000
INPUT FREQUENCY (kHz)
10000
1411 G02
Distortion vs Input Frequency
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
–100
–110
10
100
1000
INPUT FREQUENCY (kHz)
10000
1411 G03
2ND
THD
3RD
1411f
LTC1411
TYPICAL PERFOR A CE CHARACTERISTICS
Spurious Free Dynamic Range
vs Input Frequency
0
–10
–20
–30
DISTORTION (dB)
SINAD (dB)
–40
–50
–60
–70
–80
–90
–100
–110
10
100
1000
INPUT FREQUENCY (kHz)
10000
1411 G04
50
44
38
32
26
20
14
10
100
1000
INPUT FREQUENCY (kHz)
10000
1411 G05
INL (LSB)
Differential Nonlinearity
vs Output Code
1.0
0.8
0.6
SUPPLY CURRENT (mA)
0.4
42
41
40
39
38
37
36
SUPPLY CURRENT (mA)
DNL (LSB)
0.2
0
–0.2
–0.4
–0.6
–0.8
–1.0
0
4096
8192
12288
OUTPUT CODE
16384
1411 G08
Histogram for 4096 Conversions
3500
3000
2500
2000
1500
1000
500
0
–1
0
CODE
1
1411 G13
AMPLITUDE (dB)
COUNTS
U W
S/(N + D) vs Input Frequency
and Amplitude
86
80
74
68
62
56
–40dB
–20dB
0dB
1.0
0.8
0.6
0.4
0.2
0
–0.2
–0.4
–0.6
–0.8
–1.0
Integral Nonlinearity
vs Output Code
0
4096
8192
12288
OUTPUT CODE
16384
1411 G07
Supply Current vs Temperature
45
44
43
V
DD
= 5V
46.5
44.0
41.5
39.0
36.5
34.0
31.5
–25
25
50
0
TEMPERATURE (°C)
75
100
1411 G11
Supply Current vs Supply Voltage
T
A
= 25°C
35
–50
4.5
4.75
5.0
V
DD
(V)
5.25
5.5
1411 G12
4096 Points FFT Plot (100kHz)
0
–20
–40
–60
–80
–100
–120
–140
0
250
1000
INPUT FREQUENCY (kHz)
500
750
1250
1411 G14
SINAD = 78.8dB
SFDR = 95dB
f
SAMPLE
= 2.5MHz
f
IN
= 100kHz
1411f
5
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