LTC1197/LTC1197L
LTC1199/LTC1199L
10-Bit, 500ksps ADCs in
MSOP with Auto Shutdown
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FEATURES
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DESCRIPTIO
8-Pin MSOP and SO Packages
10-Bit Resolution at 500ksps
Single Supply: 5V or 3V
Low Power at Full Speed:
25mW Typ at 5V
2.2mW Typ at 2.7V
Auto Shutdown Reduces Power Linearly
at Lower Sample Rates
10-Bit Upgrade to 8-Bit LTC1196/LTC1198
SPI and MICROWIRETM Compatible Serial I/O
Low Cost
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APPLICATIO S
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High Speed Data Acquisition
Portable or Compact Instrumentation
Low Power or Battery-Operated Instrumentation
The LTC ®1197/LTC1197L/LTC1199/LTC1199L are
10-bit A/D converters with sampling rates up to 500kHz.
They have 2.7V (L) and 5V versions and are offered in
8-pin MSOP and SO packages. Power dissipation is typically only 2.2mW at 2.7V (25mW at 5V) during full speed
operation. The automatic power down reduces supply
current linearly as sample rate is reduced. These 10-bit,
switched-capacitor, successive approximation ADCs include a sample-and-hold. The LTC1197/LTC1197L have a
differential analog input with an adjustable reference pin.
The LTC1199/LTC1199L offer a software-selectable
2-channel MUX.
The 3-wire serial I/O, MSOP and SO-8 packages, 2.7V
operation and extremely high sample rate-to-power ratio
make these ADCs ideal choices for compact, low power
high speed systems.
These circuits can be used in ratiometric applications or
with external references. The high impedance analog
inputs and the ability to operate with reduced spans below
1V full scale (LTC1197/LTC1197L) allow direct connection to signal sources in many applications, eliminating
the need for gain stages.
, LTC and LT are registered trademarks of Linear Technology Corporation.
MICROWIRE is a trademark of National Semiconductor Corporation.
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TYPICAL APPLICATIO
Supply Current vs Sampling Frequency
Single 2.7V Supply, 250ksps, 10-Bit Sampling ADC
10000
1µF
LTC1197L
1
2
ANALOG INPUT
0V TO 2.7V RANGE 3
4
CS
VCC
+IN
CLK
– IN
DOUT
GND
VREF
8
7
6
SERIAL DATA LINK TO
ASIC, PLD, MPU, DSP
OR SHIFT REGISTERS
SUPPLY CURRENT (µA)
1000
2.7V
VCC = 5V
fCLK = 7.2MHz
100
10
VCC = 2.7V
fCLK = 3.5MHz
1
5
1197/99 TA01
0.1
0.01
0.1
10
100
1
SAMPLING FREQUENCY (kHz)
1000
1197/99 G03
1