FEATURES
n
n
n
n
n
n
n
n
n
n
n
LTC1604
High Speed, 16-Bit, 333ksps
Sampling A/D Converter
with Shutdown
DESCRIPTION
The LTC
®
1604 is a 333ksps, 16-bit sampling A/D con-
verter that draws only 220mW from ±5V supplies. This
high performance device includes a high dynamic range
sample-and-hold, a precision reference and a high speed
parallel output. Two digitally selectable power shutdown
modes provide power savings for low power systems.
The LTC1604’s full-scale input range is ±2.5V. Outstand-
ing AC performance includes 90dB S/(N+D) and –100dB
THD at a sample rate of 333ksps.
The unique differential input sample-and-hold can acquire
single-ended or differential input signals up to its 15MHz
bandwidth. The 68dB common mode rejection allows
users to eliminate ground loops and common mode noise
by measuring signals differentially from the source.
The ADC has μP compatible,16-bit parallel output port.
There is no pipeline delay in conversion results. A separate
convert start input and a data ready signal (BUSY) ease
connections to FlFOs, DSPs and microprocessors.
L,
LTC and LT are registered trademarks of Linear Technology Corporation.
A Complete, 333ksps 16-Bit ADC
90dB S/(N+D) and –100dB THD (Typ)
Power Dissipation: 220mW (Typ)
No Pipeline Delay
No Missing Codes over Temperature
Nap (7mW) and Sleep (10μW) Shutdown Modes
Operates with Internal 15ppm/°C Reference
or External Reference
True Differential Inputs Reject Common Mode Noise
5MHz Full Power Bandwidth
±2.5V Bipolar Input Range
36-Pin SSOP Package
APPLICATIONS
n
n
n
n
n
n
Telecommunications
Digital Signal Processing
Multiplexed Data Acquisition Systems
High Speed Data Acquisition
Spectrum Analysis
Imaging Systems
TYPICAL APPLICATION
2.2μF
10μF
10Ω
36
5V 10μF
5V
10μF
LTC1604 4096 Point FFT
10
DGND
SHDN
33
CONVST
31
RD
30
BUSY
27
OV
DD
29
5V OR
3V
10μF
3
V
REF
+
35
AV
DD
+
9
+
0
–20
μP
CONTROL
LINES
AV
DD
DV
DD
4
REFCOMP
4.375V
1.75X
7.5k
+
47μF
2.5V
REF
AMPLITUDE (dB)
CONTROL
LOGIC
AND
TIMING
CS
32
–40
–60
–80
f
SAMPLE
= 333kHz
f
IN
= 100kHz
SINAD = 89dB
THD = –96dB
1 A
IN+
DIFFERENTIAL
ANALOG INPUT
±2.5V
2 A
IN
–
+
–
OGND 28
16-BIT
SAMPLING
ADC
AGND
5
AGND
6
B15 TO B0
OUTPUT
BUFFERS
16-BIT
PARALLEL
BUS
11 TO 26
D15 TO D0
AGND
7
AGND V
SS
8
34
+
–5V
10μF
+
–100
–120
–140
0
20
40
100 120 140 160
FREQUENCY (kHz)
60
1604 TA02
80
1604 TA01
1604fa
1
LTC1604
ABSOLUTE MAXIMUM RATINGS
AV
DD
= DV
DD
= OV
DD
= V
DD
(Notes 1, 2)
PACKAGE/ORDER INFORMATION
TOP VIEW
A
IN+
A
IN–
V
REF
REFCOMP
AGND
AGND
AGND
AGND
DV
DD
1
2
3
4
5
6
7
8
9
36 AV
DD
35 AV
DD
34 V
SS
33
SHDN
32
CS
31
CONV
30
RD
29 OV
DD
28 OGND
27
BUSY
26 D0
25 D1
24 D2
23 D3
22 D4
21 D5
20 D6
19 D7
G PACKAGE
36-LEAD PLASTIC SSOP
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)
V
REF
Voltage (Note 4)................... –0.3V to (V
DD
+ 0.3V)
REFCOMP Voltage (Note 4).......... –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
LTC1604C ................................................ 0°C to 70°C
LTC1604I..............................................–40°C to 85°C
Storage Temperature Range .................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec)................... 300°C
ORDER
PART NUMBER
LTC1604CG
LTC1604IG
LTC1604ACG
LTC1604AIG
DGND 10
D15 (MSB) 11
D14 12
D13 13
D12 14
D11 15
D10 16
D9 17
D8 18
T
JMAX
= 125°C,
θ
JA
= 95°C/W
Consult factory for Military grade parts.
CONVERTER CHARACTERISTICS
PARAMETER
Resolution (No Missing Codes)
Integral Linearity Error
Transition Noise
Offset Error
Offset Tempco
Full-Scale Error
Full-Scale Tempco
(Note 7)
(Note 8)
(Note 9)
(Note 9)
Internal Reference
External Reference
CONDITIONS
With Internal Reference (Notes 5, 6)
MIN
l
l
l
LTC1604
TYP
16
±1
0.7
±0.05
0.5
±0.125
±15
MAX
±4
±0.125
±0.25
±0.25
MIN
16
LTC1604A
TYP
MAX
16
±0.5
0.7
±0.05
0.5
±0.125
±15
±0.25
±0.25
±0.125
±2
UNITS
Bits
LSB
LSB
%
ppm/°C
%
%
ppm/°C
15
I
OUT
(Reference) = 0, Internal Reference
ANALOG INPUT
SYMBOL PARAMETER
V
IN
I
IN
C
IN
t
ACQ
t
AP
t
jitter
CMRR
Analog Input Range (Note 2)
Analog Input Leakage Current
Analog Input Capacitance
Sample-and-Hold Acquisition Time
Sample-and-Hold Acquisition Delay Time
Sample-and-Hold Acquisition Delay Time Jitter
Analog Input Common Mode Rejection Ratio
–2.5V < (A
IN–
= A
IN+
) < 2.5V
CONDITIONS
4.75 ≤ V
DD
≤ 5.25V, –5.25 ≤ V
SS
≤ –4.75V,
V
SS
≤ (A
IN–
, A
IN+
) ≤ AV
DD
CS
= High
Between Conversions
During Conversions
l
MIN
TYP
±2.5
MAX
UNITS
V
±1
43
5
380
–1.5
5
68
μA
pF
pF
ns
ns
ps
RMS
dB
1604fa
2
LTC1604
DYNAMIC ACCURACY
SYMBOL PARAMETER
S/N
Signal-to-Noise Ratio
(Note 5)
LTC1604
MIN
TYP MAX
l
CONDITIONS
5kHz Input Signal
100kHz Input Signal
5kHz Input Signal
100kHz Input Signal (Note 10)
5kHz Input Signal
100kHz Input Signal
100kHz Input Signal
f
IN1
= 29.37kHz, f
IN2
= 32.446kHz
LTC1604A
MIN
TYP MAX
87
90
90
90
89
–100
–94
96
–88
5
350
–88
UNITS
dB
dB
dB
dB
dB
dB
dB
dB
MHz
kHz
90
90
90
89
–100
–94
96
–88
5
350
S/(N + D) Signal-to-(Noise + Distortion) Ratio
THD
SFDR
IMD
Total Harmonic Distortion
Up to 5th Harmonic
Spurious Free Dynamic Range
Intermodulation Distortion
Full Power Bandwidth
Full Linear Bandwidth (S/(N + D) ≥ 84dB
l
l
84
INTERNAL REFERENCE 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
4.75 ≤ V
DD
≤ 5.25V
–5.25V ≤ V
SS
≤ –4.75V
0 ≤ |I
OUT
| ≤ 1mA
I
OUT
= 0
(Note 5)
MIN
2.475
TYP
2.500
±15
0.01
0.01
7.5
4.375
MAX
2.515
UNITS
V
ppm/°C
LSB/V
LSB/V
kΩ
V
DIGITAL INPUTS AND 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 D15 to D0
Hi-Z Output Capacitance D15 to D0
Output Source Current
Output Sink Current
V
DD
= 4.75V, I
OUT
= –10μA
V
DD
= 4.75V, I
OUT
= –400μA
V
DD
= 4.75V, I
OUT
= 160μA
V
DD
= 4.75V, I
OUT
= 1.6mA
V
OUT
= 0V to V
DD
,
CS
High
CS
High (Note 11)
V
OUT
= 0V
V
OUT
= V
DD
CONDITIONS
V
DD
= 5.25V
V
DD
= 4.75V
V
IN
= 0V to V
DD
(Note 5)
MIN
l
l
l
TYP
MAX
0.8
±10
UNITS
V
V
μA
pF
V
V
2.4
5
l
l
l
l
4.5
4.0
0.05
0.10
0.4
±10
15
–10
10
V
V
μA
pF
mA
mA
1604fa
3
LTC1604
POWER REQUIREMENTS
SYMBOL
V
DD
V
SS
I
DD
PARAMETER
Positive Supply Voltage
Negative Supply Voltage
Positive Supply Current
Nap Mode
Sleep Mode
Negative Supply Current
Nap Mode
Sleep Mode
Power Dissipation
Nap Mode
Sleep Mode
(Note 5)
CONDITIONS
(Notes 12, 13)
(Note 12)
CS
=
RD
= 0V
CS
= 0V,
SHDN
= 0V
CS
= 5V,
SHDN
= 0V
CS
=
RD
= 0V
CS
= 0V,
SHDN
= 0V
CS
= 5V,
SHDN
= 0V
CS
=
RD
= 0V
CS
= 0V,
SHDN
= 0V
CS
= 5V,
SHDN
= 0V
l
MIN
4.75
–4.75
TYP
MAX
5.25
–5.25
UNITS
V
V
mA
mA
μA
mA
μA
μA
mW
mW
mW
18
1.5
1
26
1
1
220
7.5
0.01
30
2.4
100
40
100
100
350
12
1
I
SS
l
P
D
l
TIMING CHARACTERISTICS
SYMBOL
f
SMPL(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
(Note 5)
CONDITIONS
l
l
l
l
l
l
l
l
l
l
MIN
333
1.5
TYP
2.45
MAX
2.8
480
3
UNITS
kHz
μs
ns
μs
ns
ns
ns
(Note 11)
(Notes 11, 12)
(Notes 11, 12)
(Notes 11, 12)
CS
= Low (Note 12)
(Note 12)
C
L
= 25pF
Throughput Time (Acquisition + Conversion)
CS
to
RD
Setup Time
CS↓
to
CONVST↓
Setup Time
SHDN↓
to
CS↑
Setup Time
SHDN↑
to
CONVST↓
Wake-Up Time
CONVST
Low Time
CONVST
to
BUSY
Delay
Data Ready Before
BUSY↑
Delay Between Conversions
Wait Time
RD↓
After
BUSY↑
Data Access Time After
RD↓
(Note 12)
(Note 12)
C
L
= 25pF
C
L
= 100pF
0
10
10
400
40
36
80
60
32
200
–5
40
45
50
50
60
60
75
60
70
75
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
l
l
l
l
l
l
l
l
t
11
Bus Relinquish Time
LTC1604C
LTC1604I
t
12
t
13
t
14
RD
Low Time
CONVST
High Time
Aperture Delay of Sample-and-Hold
(Note 12)
(Note 12)
t
10
40
2
ns
1604fa
4
LTC1604
TIMING CHARACTERISTICS
(Note 5)
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:
Typical RMS noise at the code transitions. See Figure 17 for
histogram.
Note 9:
Bipolar offset is the offset voltage measured from –0.5LSB when
the output code flickers between 0000 0000 0000 0000 and 1111 1111
1111 1111.
Note 10:
Signal-to-Noise Ratio (SNR) is measured at 5kHz and distortion
is measured at 100kHz. These results are used to calculate Signal-to-Nosie
Plus Distortion (SINAD).
Note 11:
Guaranteed by design, not subject to test.
Note 12:
Recommended operating conditions.
Note 13:
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 either within 250ns
after conversion start or after
BUSY
rises.
The
l
denotes specifications that apply over the full operating temperature
range.
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
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, V
SS
= –5V, f
SMPL
= 333kHz, and t
r
= t
f
= 5ns unless
otherwise specified.
Note 6:
Linearity, offset and full-scale specification apply for a single-
ended A
IN+
input with A
IN–
grounded.
TYPICAL PERFORMANCE CHARACTERISTICS
Integral Nonlinearity vs
Output Code
2.0
1.5
1.0
DNL (LSB)
INL (LSB)
0.5
0.0
–0.5
–1.0
–1.5
–2.0
–32768
1.0
0.8
0.6
0.4
SINAD (dB)
0.2
0.0
–0.2
–0.4
–0.6
–0.8
–1.0
–16384
0
CODE
1604 G11
Differential Nonlinearity vs
Output Code
100
90
80
70
60
50
40
30
20
10
0
–16384
0
CODE
1604 G10
S/(N + D) vs Input Frequency
and Amplitude
V
IN
= 0dB
V
IN
= –20dB
V
IN
= –40dB
16384
32767
–32768
16384
32767
1k
10k
100k
FREQUENCY (Hz)
1M
1604 G01
Signal-to-Noise Ratio vs
Input Frequency
AMPLITUDE (dB BELOW THE FUNDAMENTAL)
100
90
SIGNAL-TO-NOISE RATIO (dB)
80
70
60
50
40
30
20
10
0
1k
10k
100k
FREQUENCY (Hz)
1M
1604 G03
Distortion vs Input Frequency
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
–100
–110
1k
100k
INPUT FREQUENCY (Hz)
10k
THD
3RD
2ND
1M
1604 G04
Spurious-Free Dynamic Range
vs Input Frequency
0
SPURIOUS-FREE DYNAMIC RANGE (dB)
–10
–20
–30
–40
–50
–60
–70
–80
–90
–100
–110
1k
100k
INPUT FREQUENCY (Hz)
10k
1M
1604 G05
1604fa
5
京公网安备 11010802033920号
EEWORLD
