FEATURES
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LTC1401
Complete
SO-8, 12-Bit, 200ksps
ADC with Shutdown
DESCRIPTIO
The LTC
®
1401 is a complete 200ksps, 12-bit A/D con-
verter that converts 0V to 2.048V unipolar input and draws
only 15mW from a single 3V supply. This easy-to-use
device comes complete with a 315ns sample-and-hold
and a precision reference. Maximum DC specifications
include
±1LSB
INL,
±1LSB
DNL and 45ppm/°C full-scale
drift over temperature.
The LTC1401 has three power saving modes: Nap and
Sleep, through the serial interface and Shutdown by
setting the SHDN pin to zero. In Nap mode, it consumes
only 1.5mW of power and can wake up and convert
immediately. In Sleep (Shutdown) mode, it consumes
19.5µW (13.5µW) of power typically. Upon power-up
from Sleep or Shutdown mode, a reference ready (REFRDY)
signal is available in the serial word to indicate that the
reference has settled and the chip is ready to convert.
The 3-wire serial port allows compact and efficient data
transfer to a wide range of microprocessors, microcon-
trollers and DSPs.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
Complete 12-Bit ADC with Reference in SO-8
Single Supply 3V Operation
Sample Rate: 200ksps
Power Dissipation: 15mW (Typ)
68dB S/(N + D) and – 72dB THD at 50kHz
No Missing Codes Over Temperature
Nap Mode with Instant Wake-Up: 1.5mW
Sleep Mode: 19.5µW
Shutdown Mode: 13.5µW
High Impedance Analog Input
Input Range (0.5mV/LSB): 0V to 2.048V
Internal Reference Can Be Overdriven Externally
3-Wire Interface to DSPs and Processors (SPI and
MICROWIRE
TM
Compatible)
APPLICATIO S
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Low Power and Battery-Operated Systems
Handheld or Portable Instruments
High Speed Data Acquisition
Digital Signal Processing
Multiplexed Data Acquisition Systems
Telecommunication
Digital Radio
Spectrum Analysis
TYPICAL APPLICATIO
Power Consumption vs Sample Rate
100
3.2MHz CLOCK
T
A
= 25°C
10
SUPPLY CURRENT (mA)
Single 3V Supply, 200kHz, 12-Bit Sampling A/D Converter
3V
NORMAL CONVERSION
NAP MODE
BETWEEN CONVERSION
+
10µF
ANALOG INPUT
(0V TO 2.048V)
1.20V
10µF
0.1µF
V
CC
SHDN
LTC1401
MPU
P1.4
P1.3
P1.2
SERIAL
DATA LINK
1401 TA01
1
0.1
SHUTDOWN MODE
BETWEEN CONVERSION
SLEEP MODE BETWEEN
CONVERSION
A
IN
V
REF
0.1µF
GND
CONV
CLK
D
OUT
0.01
+
0.001
0.01 0.1
U
1
U
U
10 100 1k 10k 100k 1M
SAMPLE RATE (Hz)
LTC1401 • TA02
1401fa
1
LTC1401
ABSOLUTE
MAXIMUM
RATINGS
(Notes 1, 2)
PACKAGE/ORDER INFORMATION
TOP VIEW
V
CC
1
A
IN
2
V
REF
3
GND 4
8 SHDN
7 CONV
6 CLK
5 D
OUT
Supply Voltage (V
CC
) ................................................. 7V
Analog Input Voltage (Note 3) ..... – 0.3V to (V
CC
+ 0.3V)
Digital Input Voltage (Note 4) ....................– 0.3V to 12V
Digital Output Voltage .................. – 0.3V to (V
CC
+ 0.3V)
Power Dissipation .............................................. 300mW
Operating Ambient Temperature Range
LTC1401C ............................................... 0°C to 70°C
LTC1401I ............................................ – 40°C to 85°C
Operating Junction Temperature ......................... 125°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
S8 PACKAGE
8-LEAD PLASTIC SO
T
JMAX
= 125°C,
θ
JA
= 130°C/W
ORDER PART NUMBER
LTC1401CS8
LTC1401IS8
S8 PART MARKING
1401
1401I
Order Options
Tape and Reel: Add #TR
Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF
Lead Free Part Marking:
http://www.linear.com/leadfree/
Consult LTC Marketing for parts specified with wider operating temperature ranges.
POWER REQUIRE E TS
SYMBOL
V
CC
I
CC
PARAMETER
Supply Voltage
Supply Current
The
●
denotes specifications which apply over the full operating temperature range,
unless otherwise noted specifications are at T
A
= 25°C. V
CC
= 3V, f
SAMPLE
= 200kHz, t
r
= t
f
= 5ns, unless otherwise specified.
CONDITIONS
f
SAMPLE
= 200ksps
Nap Mode
Sleep Mode
Shutdown Mode
f
SAMPLE
= 200ksps
Nap Mode
Sleep Mode
Shutdown Mode
●
●
●
●
●
●
●
●
MIN
2.7
P
D
Power Dissipation
TYP
3.0
5
0.5
6.5
4.5
15
1.5
19.5
13.5
MAX
3.6
10
1.0
15
10
30
3.0
45
30
UNITS
V
mA
mA
µA
µA
mW
mW
µW
µW
A ALOG I PUT
SYMBOL PARAMETER
V
IN
I
IN
C
IN
Analog Input Range
The
●
denotes specifications which apply over the full operating temperature range, unless otherwise
noted specifications are at T
A
= 25°C. V
CC
= 3V, f
SAMPLE
= 200kHz, t
r
= t
f
= 5ns, unless otherwise specified.
CONDITIONS
●
MIN
●
TYP
0 to 2.048
MAX
±1
UNITS
V
µA
pF
pF
Analog Input Leakage Current
Analog Input Capacitance
During Conversions (Hold Mode)
Between Conversions (Sample Mode)
During Conversions (Hold Mode)
45
5
I TER AL REFERE CE CHARACTERISTICS
PARAMETER
V
REF
Output Voltage
V
REF
Output Tempco
V
REF
Line Regulation
V
REF
Load Regulation
V
REF
Wake-Up Time from Sleep or Shutdown Mode
CONDITIONS
I
OUT
= 0
I
OUT
= 0
2.7V
≤
V
CC
≤
3.6V
0
≤
⏐
I
OUT
⏐
≤
1mA
C
VREF
= 10µF
The
●
denotes specifications which apply over the full
operating temperature range, unless otherwise noted specifications are at T
A
= 25°C. V
CC
= 3V, f
SAMPLE
= 200kHz, t
r
= t
f
= 5ns, unless
otherwise specified.
MIN
1.180
●
TYP
1.200
±10
0.01
2
3
MAX
1.220
±45
UNITS
V
ppm/°C
LSB/ V
LSB/mA
ms
1401fa
2
U
W
U
U
UW
W W
U
W
U
U
U
U
LTC1401
CO VERTER CHARACTERISTICS
The
●
denotes specifications which apply over the full operating temperature
range, unless otherwise noted specifications are at T
A
= 25°C. With internal reference V
CC
= 3V, f
SAMPLE
= 200kHz, t
r
= t
f
= 5ns, unless
otherwise specified.
CONDITIONS
●
PARAMETER
Resolution (No Missing Codes)
Integral Linearity Error
Differential Linearity Error
Offset Error
Full-Scale Error
Full-Scale Tempco
I
OUT(REF)
= 0
●
DY A IC ACCURACY
SYMBOL PARAMETER
S/(N + D) Signal-to-Noise
Plus Distortion Ratio
THD
Total Harmonic Distortion
Up to 5th Harmonic
Peak Harmonic or
Spurious Noise
IMD
Intermodulation Distortion
Full Power Bandwidth
The
●
denotes specifications which apply over the full operating temperature range, unless
otherwise noted specifications are at T
A
= 25°C. V
CC
= 3V, f
SAMPLE
= 200kHz, t
r
= t
f
= 5ns, unless otherwise specified.
CONDITIONS
50kHz Input Signal
100kHz Input Signal
50kHz Input Signal
100kHz Input Signal
50kHz Input Signal
100kHz Input Signal
f
IN1
= 49.853kHz, f
IN2
= 53.076kHz
●
●
●
DIGITAL I PUTS AND OUTPUTS
The
●
denotes specifications which apply over the full operating temperature
range, unless otherwise noted specifications are at T
A
= 25°C. V
CC
= 3V, f
SAMPLE
= 200kHz, t
r
= t
f
= 5ns, unless otherwise specified.
CONDITIONS
V
CC
= 3.6V
V
CC
= 2.7V
V
IN
= 0V to V
CC
V
CC
= 2.7V, I
O
= – 10µA
V
CC
= 2.7V, I
O
= – 200µA
V
CC
= 2.7V, I
O
= 400µA
V
OUT
= 0V to V
CC
V
OUT
= 0V
V
OUT
= V
CC
●
●
●
SYMBOL PARAMETER
V
IH
V
IL
I
IN
C
IN
V
OH
V
OL
I
OZ
C
OZ
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
Hi-Z Output Leakage D
OUT
Hi-Z Output Capacitance D
OUT
Output Source Current
Output Sink Current
U
U
W U
U
MIN
12
●
●
●
TYP
MAX
±1
±1
±6
±8
±15
UNITS
Bits
LSB
LSB
LSB
LSB
LSB
ppm/°C
(Note 6)
±10
±45
MIN
65
TYP
68
65
– 72
– 66
– 74
– 67
– 69
2
50
MAX
UNITS
dB
dB
– 65
– 65
dB
dB
dB
dB
dB
MHz
kHz
Full Linear Bandwidth (S/(N + D)
≥
68dB)
MIN
2.0
TYP
MAX
0.8
±10
UNITS
V
V
µA
pF
V
V
5
●
●
●
●
2.40
2.25
2.64
2.50
0.13
15
–5
10
0.4
±10
V
µA
pF
mA
mA
1401fa
3
LTC1401
TI I G CHARACTERISTICS
SYMBOL
f
SAMPLE(MAX)
t
CONV
t
ACQ
f
CLK
t
CLK
t
WK(NAP)
t
1
t
2
t
3
t
4
t
5
t
6
t
7
t
8
t
9
t
10
t
11
PARAMETER
Maximum Sampling Frequency
Conversion Time
Acquisition Time
CLK Frequency
CLK Pulse Width
Time to Wake Up from Nap Mode
The
●
denotes specifications which apply over the full operating temperature range,
unless otherwise noted specifications are at T
A
= 25°C. V
CC
= 3V, f
SAMPLE
= 200kHz, t
r
= t
f
= 5ns, unless otherwise specified.
CONDITIONS
●
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2:
All voltage values are with respect to GND.
Note 3:
When these pin voltages are taken below GND or above V
CC
, they
will be clamped by internal diodes. This product can handle input currents
greater than 40mA without latch-up if the pin is driven below GND or
above V
CC
.
Note 4:
When these pin voltages are taken below GND, they will be clamped
by internal diodes. This product can handle input currents greater than 40mA
without latch-up if the pin is driven below GND. These pins are not clamped
to V
CC
.
4
UW
MIN
200
●
TYP
MAX
4.1
UNITS
kHz
µs
ns
MHz
ns
ns
ns
ns
ns
ns
f
CLK
= 3.2MHz
315
●
0.1
60
350
60
100
0
50
80
45
3.2
(Notes 5 and 8)
●
●
●
●
CLK Pulse Width to Return to Active Mode
CONV↑ to CLK↑ Setup Time
CONV↑ After Leading CLK↑
CONV Pulse Width
Time from CLK↑ to Sample Mode
Aperture Delay of Sample-and-Hold
Minimum Delay Between Conversion
Delay Time, CLK↑ to D
OUT
Valid
Delay Time, CLK↑ to D
OUT
Hi-Z
Time from Previous Data Remains Valid After CLK↑
Jitter < 50ps
(Note 5)
C
LOAD
= 20pF
C
LOAD
= 20pF
C
LOAD
= 20pF
(Note 7)
●
ns
ns
550
120
120
ns
ns
ns
ns
ns
●
●
●
●
●
350
60
60
15
50
50
Minimum Time Between Nap/Sleep Request to Wake Up Request (Notes 5 and 8)
Note 5:
Guaranteed by design, not subject to test.
Note 6:
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 7:
The rising edge of CONV starts a conversion. If CONV returns low
at a bit decision point during the conversion, it can create small errors. For
best performance, ensure that CONV returns low either within 120ns after
the conversion starts (i.e., before the first bit decision) or after the 14
clock cycles. (Figure 13 Timing Diagram).
Note 8:
If this timing specification is not met, the device may not respond
to a request for a conversion. To recover from this condition a NAP
request is required.
1401fa
LTC1401
TYPICAL PERFORMANCE CHARACTERISTICS
Differential Nonlinearity vs
Output Code
1.0
f
SAMPLE
= 200kHz
0.5
DNL ERROR (LSBs)
INL ERROR (LSBs)
0.5
SIGNAL/(NOISE + DISTORTION)(dB)
0
–0.5
–1.0
0
512
1024
1536
2048
2560
3072
3584
4096
CODE
LTC1401 • TPC01
Signal-to-Noise Ratio (Without
Harmonics) vs Input Frequency
80
SPURIOUS-FREE DYNAMIC RANGE (dB)
70
SIGNAL-TO-NOISE RATIO (dB)
60
50
40
30
20
10
0
10
100
INPUT FREQUENCY (kHz)
1000
LTC1401 • TPC04
–40
–50
–60
–70
–80
–90
10
100
INPUT FREQUENCY (kHz)
1000
LTC1401 • TPC05
t
ACQ
(ns)
T
A
= 25°C
f
SAMPLE
= 200kHz
Reference Voltage vs
Load Current
1.40
POWER SUPPLY FEEDTHROUGH (dB)
1.35
REFERENCE VOLTAGE (V)
T
A
= 25°C
1.30
1.25
1.20
1.15
1.10
1.05
1.00
0.95
0.90
–7 –6
–5
–4 –3 –2 –1 0
LOAD CURRENT (mA)
1
2
–30
–40
–50
–60
–70
–80
–90
–100
1
10
100
RIPPLE FREQUENCY (kHz)
1000
LTC1401 • TPC08
SUPPLY CURRENT (mA)
U W
Integral Nonlinearity vs
Output Code
1.0
f
SAMPLE
= 200kHz
70
60
50
40
30
20
10
0
80
S/(N + D) vs Input Frequency
and Amplitude
V
IN
= 0dB
T
A
= 25°C
f
SAMPLE
= 200kHz
V
IN
= –20dB
0
–0.5
V
IN
= –60dB
–1.0
0
512
1024
1536
2048
2560
3072
3584
4096
CODE
LTC1401 • TPC02
10
100
INPUT FREQUENCY (kHz)
1000
LTC1401 • TPC03
Peak Harmonic or Spurious Noise
vs Input Frequency
0
–10
–20
–30
T
A
= 25°C
f
SAMPLE
= 200kHz
Acquisition Time vs
Source Impedance
4500
4000
3500
3000
2500
2000
1500
1000
500
0
10
100
1k
SOURCE RESISTANCE (Ω)
10k
T
A
= 25°C
LTC1401 • TPC06
Power Supply Feedthrough vs
Ripple Frequency
0
–10
–20
f
SAMPLE
= 200kHz
f
IN
= 49.853kHz
V
CC
(V
RIPPLE
= 1mV)
12
Supply Current vs Temperature
f
SAMPLE
= 200kHz
10
V
IN
= 3.6V
8
6
4
2
0
–50 –25
V
IN
= 3V
V
IN
= 2.7V
50
25
75
0
TEMPERATURE (˚C)
100
125
LTC1401 • TPC07
LTC1401 • TPC09
1401fa
5