LTC1419
14-Bit, 800ksps Sampling
A/D Converter with Shutdown
FEATURES
s
s
s
s
s
s
s
DESCRIPTIO
s
s
s
s
Sample Rate: 800ksps
Power Dissipation: 150mW
81.5dB S/(N + D) and 93dB THD
No Missing Codes
No Pipeline Delay
Nap and Sleep Shutdown Modes
Operates with 2.5V Internal 15ppm/°C
Reference or External Reference
True Differential Inputs Reject Common Mode Noise
20MHz Full-Power Bandwidth Sampling
Bipolar Input Range:
±2.5V
28-Pin SSOP and SO Packages
The LTC
®
1419 is a 1µs, 800ksps, 14-bit sampling
A/D converter that draws only 150mW from
±5V
supplies.
This easy-to-use device includes a high dynamic range
sample-and-hold and a precision reference. Two digitally
selectable power shutdown modes provide flexibility for
low power systems.
The LTC1419 has a full-scale input range of
±2.5V.
Out-
standing AC performance includes 81.5dB S/(N + D) and
93dB THD with a 100kHz input; 80dB S/(N + D) and 86dB
THD at the Nyquist input frequency of 400kHz.
The unique differential input sample-and-hold can acquire
single-ended or differential input signals up to its 20MHz
bandwidth. The 60dB common mode rejection allows
users to eliminate ground loops and common mode noise
by measuring signals differentially from the source.
The ADC has a
µP
compatible, 14-bit parallel output port.
There is no pipeline delay in the conversion results. A
separate convert start input and data ready signal (BUSY)
ease connections to FIFOs, DSPs and microprocessors.
, LTC and LT are registered trademarks of Linear Technology Corporation.
APPLICATI
s
s
s
s
s
s
S
Telecommunications
Digital Signal Processing
Multiplexed Data Acquisition Systems
High Speed Data Acquisition
Spectrum Analysis
Imaging Systems
TYPICAL APPLICATI
800kHz, 14-Bit Sampling A/D Converter
LTC1419
1
DIFFERENTIAL
AV
DD
ANALOG INPUT 2 +A
IN
(–2.5V TO 2.5V)
–A
IN
DV
DD
3
V
REF
V
SS
4
REFCOMP
BUSY
5
10µF
AGND
CS
6
D13(MSB) CONVST
7
D12
RD
8
D11
SHDN
9
D10
D0
10
D9
D1
11
D8
D2
14-BIT
12
PARALLEL
D7
D3
BUS
13
D6
D4
14
DGND
D5
5V
28
27
26
25
24
23
22
21
20
19
18
17
16
15
µP
CONTROL
LINES
10µF
–5V
10µF
Effective Bits and Signal-to-(Noise + Distortion)
vs Input Frequency
14
13
12
11
EFFECTIVE BITS
10
9
8
7
6
5
4
3
2
1k
f
SAMPLE
= 800kHz
10k
100k
INPUT FREQUENCY (Hz)
1M 2M
1419 TA02
V
REF
OUTPUT
2.50V
1µF
1419 TA01
U
86
80
74
68
62
S/(N + D) (dB)
UO
UO
1
LTC1419
ABSOLUTE
AXI U
RATI GS
PACKAGE/ORDER I FOR ATIO
TOP VIEW
+A
IN
1
–A
IN
2
V
REF
3
REFCOMP 4
AGND 5
D13(MSB) 6
D12 7
D11 8
D10 9
D9 10
D8 11
D7 12
D6 13
DGND 14
28 AV
DD
27 DV
DD
26 V
SS
25 BUSY
24 CS
23 CONVST
22 RD
21 SHDN
20 D0
19 D1
18 D2
17 D3
16 D4
15 D5
AV
DD
= V
DD
= DV
DD
(Notes 1, 2)
Supply Voltage (V
DD
) ................................................ 6V
Negative Supply Voltage (V
SS
)................................ – 6V
Total Supply Voltage (V
DD
to V
SS
) .......................... 12V
Analog Input Voltage (Note 3)
......................................... (V
SS
– 0.3V) to (V
DD
+ 0.3V)
Digital Input Voltage (Note 4) ......... (V
SS
– 0.3V) to 10V
Digital Output Voltage ........ (V
SS
– 0.3V) to (V
DD
+ 0.3V)
Power Dissipation............................................. 500mW
Operating Temperature Range
LTC1419C............................................... 0°C to 70°C
LTC1419I........................................... – 40°C to 85°C
Storage Temperature Range ................ – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
ORDER
PART NUMBER
LTC1419ACG
LTC1419ACSW
LTC1419AIG
LTC1419AISW
LTC1419CG
LTC1419CSW
LTC1419IG
LTC1419ISW
G PACKAGE
SW PACKAGE
28-LEAD PLASTIC SSOP 28-LEAD PLASTIC SO WIDE
T
JMAX
= 110°C,
θ
JA
= 95°C/W (G)
T
JMAX
= 110°C,
θ
JA
= 130°C/W (SW)
Consult factory for Military grade parts.
CO VERTER CHARACTERISTICS
PARAMETER
Resolution (No Missing Codes)
Integral Linearity Error
Differential Linearity Error
Offset Error
Full-Scale Error
Full-Scale Tempco
(Note 8)
Internal Reference
External Reference = 2.5V
I
OUT(REF)
= 0
(Note 7)
CONDITIONS
With Internal Reference (Notes 5, 6)
MIN
q
q
q
q
LTC1419
TYP
±0.8
±0.7
±5
±10
±5
±15
MAX
±2
±1.5
±20
±60
MIN
14
LTC1419A
TYP
MAX
±0.6
±0.5
±5
±10
±5
±15
±1.25
±1
±20
±60
UNITS
Bits
LSB
LSB
LSB
LSB
LSB
ppm/°C
13
A ALOG I PUT
SYMBOL PARAMETER
V
IN
I
IN
C
IN
t
ACQ
t
AP
t
jitter
CMRR
(Note 5)
CONDITIONS
4.75V
≤
V
DD
≤
5.25V, –5.25
≤
V
SS
≤
– 4.75V
CS = High
Between Conversions
During Conversions
q
q
q
MIN
TYP
±2.5
MAX
±1
UNITS
V
µA
pF
pF
Analog Input Range (Note 9)
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
15
5
90
–1.5
2
300
ps
RMS
dB
– 2.5V < (– A
IN
= A
IN
) < 2.5V
60
2
U
ns
ns
W
U
U
W W
W
U
U
U
LTC1419
DY A IC ACCURACY
SYMBOL
S/(N + D)
THD
SFDR
IMD
PARAMETER
I TER AL REFERE CE CHARACTERISTICS
PARAMETER
V
REF
Output Voltage
V
REF
Output Tempco
V
REF
Line Regulation
V
REF
Output Resistance
REFCOMP Output Voltage
CONDITIONS
I
OUT
= 0
I
OUT
= 0
DIGITAL I PUTS A D DIGITAL OUTPUTS
SYMBOL PARAMETER
V
IH
V
IL
I
IN
C
IN
V
OH
High Level Input Voltage
Low Level Input Voltage
Digital Input Current
Digital Input Capacitance
High Level Output Voltage
V
DD
= 4.75V
I
O
= – 10µA
I
O
= – 200µA
V
DD
= 4.75V
I
O
= 160µA
I
O
= 1.6mA
V
OUT
= 0V to V
DD
, CS High
CS High (Note 9 )
V
OUT
= 0V
V
OUT
= V
DD
CONDITIONS
V
DD
= 5.25V
V
DD
= 4.75V
V
IN
= 0V to V
DD
V
OL
Low Level Output Voltage
I
OZ
C
OZ
I
SOURCE
I
SINK
Hi-Z Output Leakage D13 to D0
Hi-Z Output Capacitance D13 to D0
Output Source Current
Output Sink Current
POWER REQUIRE E TS
SYMBOL PARAMETER
V
DD
V
SS
I
DD
Positive Supply Voltage
Negative Supply Voltage
Positive Supply Current
Nap Mode
Sleep Mode
Negative Supply Current
Nap Mode
Sleep Mode
I
SS
U W
U
U
U
W U
U
(Note 5)
CONDITIONS
100kHz Input Signal
390kHz Input Signal
100kHz Input Signal, First 5 Harmonics
390kHz Input Signal, First 5 Harmonics
100kHz Input Signal
f
IN1
= 29.37kHz, f
IN2
= 32.446kHz
S/(N + D)
≥
77dB
q
q
q
MIN
78
TYP
81.5
80.0
– 93
– 86
– 95
– 86
20
1
MAX
UNITS
dB
dB
Signal-to-(Noise + Distortion) Ratio
Total Harmonic Distortion
Spurious Free Dynamic Range
Intermodulation Distortion
Full-Power Bandwidth
Full-Linear Bandwidth
– 86
– 86
dB
dB
dB
dB
MHz
MHz
U
(Note 5)
MIN
2.480
TYP
2.500
±15
0.05
2
4.06
MAX
2.520
UNITS
V
ppm/°C
LSB/V
kΩ
V
4.75V
≤
V
DD
≤
5.25V, – 5.25
≤
V
SS
≤
– 4.75V
– 0.1mA
≤
I
OUT
≤
0.1mA
I
OUT
= 0
(Note 5)
MIN
q
q
q
TYP
MAX
0.8
±10
UNITS
V
V
µA
pF
V
V
V
V
µA
pF
mA
mA
2.4
5
4.5
q
4.0
0.05
0.10
q
q
q
0.4
±10
15
– 10
10
(Note 5)
CONDITIONS
(Notes 10, 11)
(Note 10)
q
MIN
4.75
– 4.75
TYP
MAX
5.25
– 5.25
UNITS
V
V
mA
mA
µA
mA
µA
µA
SHDN = 0V, CS = 0V
SHDN = 0V, CS = 5V
q
11
1.5
250
19
100
1
20
30
SHDN = 0V, CS = 0V
SHDN = 0V, CS = 5V
3
LTC1419
POWER REQUIRE E TS
SYMBOL PARAMETER
P
DIS
Power Dissipation
Nap Mode
Sleep Mode
TI I G CHARACTERISTICS
SYMBOL
f
SAMPLE(MAX)
t
CONV
t
ACQ
t
ACQ + CONV
t
1
t
2
t
3
t
4
t
5
t
6
t
7
t
8
t
9
t
10
PARAMETER
Maximum Sampling Frequency
Conversion Time
Acquisition Time
Acquisition + Conversion Time
CS to RD Setup Time
CS↓ to CONVST↓ Setup Time
CS↓ to SHDN↓ Setup Time
CONVST Low Time
CONVST to BUSY Delay
Data Ready Before BUSY↑
SHDN↑ to CONVST↓ Wake-Up Time (Note 10)
(Notes 10, 11)
C
L
= 25pF
q
q
q
Delay Between Conversions
Wait Time RD↓ After BUSY↑
Data Access Time After RD↓
t
11
Bus Relinquish Time
0°C
≤
T
A
≤
70°C
– 40°C
≤
T
A
≤
85°C
RD Low Time
CONVST High Time
q
q
q
q
t
12
t
13
The
q
denotes specifications which apply over the full operating
temperature range; all other limits and typicals T
A
= 25°C.
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 and
AGND wired together unless otherwise noted.
Note 3:
When these pin voltages are taken below V
SS
or above V
DD
, they
will be clamped by internal diodes. This product can handle input currents
greater than 100mA below V
SS
or above V
DD
without latchup.
Note 4:
When these pin voltages are taken below V
SS
, they will be clamped
by internal diodes. This product can handle input currents greater than
100mA below V
SS
without latchup. These pins are not clamped
to V
DD
.
Note 5:
V
DD
= 5V, f
SAMPLE
= 800kHz, t
r
= t
f
= 5ns unless otherwise
specified.
4
U W
(Note 5)
CONDITIONS
q
MIN
TYP
150
7.5
1.2
MAX
240
12
UNITS
mW
mW
mW
SHDN = 0V, CS = 0V
SHDN = 0V, CS = 5V
UW
(Note 5)
MIN
q
q
q
q
CONDITIONS
TYP
950
90
1040
MAX
1150
300
1250
UNITS
kHz
ns
ns
ns
ns
ns
ns
800
(Notes 9, 10)
(Notes 9, 10)
(Notes 9, 10)
q
q
0
40
40
400
40
20
50
20
15
40
–5
15
25
35
35
50
20
25
30
50
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
(Note 10)
C
L
= 25pF
q
q
q
C
L
= 100pF
q
20
10
t
10
40
Note 6:
Linearity, offset and full-scale specifications apply for a single-
ended +A
IN
input with – A
IN
grounded.
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:
Guaranteed by design, not subject to test.
Note 10:
Recommended operating conditions.
Note 11:
The falling edge of CONVST 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 either
within 650ns after the start of the conversion or after BUSY rises.
LTC1419
TYPICAL PERFORMANCE CHARACTERISTICS
S/(N + D) vs Input Frequency
and Amplitude
90
90
AMPLITUDE (dB BELOW THE FUNDAMENTAL)
SIGNAL/(NOISE + DISTORTION) (dB)
80
70
60
50
40
30
20
10
0
1k
SIGNAL-TO -NOISE RATIO (dB)
V
IN
= 0dB
V
IN
= –20dB
V
IN
= –60dB
100k
10k
INPUT FREQUENCY (Hz)
Spurious-Free Dynamic Range
vs Input Frequency
0
0
– 20
AMPLITUDE (dB)
SPURIOUS-FREE DYNAMIC RANGE (dB)
–10
–20
–30
–40
–50
–60
–70
–80
– 90
–100
–110
10k
–120
100k
INPUT FREQUENCY (Hz)
1M
2M
0
50
–100
– 40
– 60
– 80
DNL ERROR (LSBs)
AMPLITUDE OF POWER SUPPLY FEEDTHROUGH (dB)
Integral Nonlinearity
vs Output Code
1.0
–20
–30
–40
–50
–60
–70
–80
–90
–100
1k
DGND
100k
10k
RIPPLE FREQUENCY (Hz)
1M
2M
V
DD
V
SS
0.5
COMMON MODE REJECTION (dB)
INL ERROR (LSBs)
0
– 0.5
–1.0
0
4096
12288
8192
OUTPUT CODE
16384
1419 G07
U W
1419 G01
1419 G04
Signal-to-Noise Ratio
vs Input Frequency
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
–100
– 110
80
70
60
50
40
30
20
10
0
Distortion vs Input Frequency
THD
2ND
3RD
1k
10k
100k
INPUT FREQUENCY (Hz)
1M 2M
1419 G03
1M 2M
1k
10k
100k
INPUT FREQUENCY (Hz)
1M 2M
1419 G02
Intermodulation Distortion Plot
f
SAMPLE
= 800kHz
f
IN1
= 95.8984375kHz
f
IN2
= 104.1015625kHz
Differential Nonlinearity
vs Output Code
1.0
0.5
0
– 0.5
100 150 200 250 300 350 400
FREQUENCY (kHz)
1419 G05
–1.0
0
4096
12288
8192
OUTPUT CODE
16384
1419 G06
Power Supply Feedthrough
vs Ripple Frequency
0
–10
80
70
60
50
40
30
20
10
0
Input Common Mode Rejection
vs Input Frequency
1
1000
10
100
INPUT FREQUENCY (Hz)
10000
1419 G09
1419 G08
5
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