LTC1273
LTC1275/LTC1276
12-Bit, 300ksps Sampling
A/D Converters with Reference
U
FEATURES
DESCRIPTIO
The LTC®1273/LTC1275/LTC1276 are 300ksps, sam-
pling 12-bit A/D converters that draw only 75mW from
single 5V or ±5V supplies. These easy-to-use devices
come complete with 600ns sample-and-holds, precision
references and internally trimmed clocks. Unipolar and
bipolar conversion modes provide flexibility for various
applications. They are built with LTBiCMOSTM switched
capacitor technology.
■
Single Supply 5V or ±5V Operation
■
300ksps Sample Rate
■
75mW (Typ) Power Dissipation
■
On-Chip 25ppm/°C Reference
■
Internal Synchronized Clock; No Clock Required
■
High Impedance Analog Input
■
70dB S/(N + D) and 77dB THD at Nyquist
■
±1/2LSB INL and ±3/4LSB DNL Max (A Grade)
■
ESD Protected On All Pins
These devices have 25ppm/°C (max) internal references.
The LTC1273 converts 0V to 5V unipolar inputs from a
single 5V supply. The LTC1275/LTC1276 convert ±2.5V
and ±5V respectively from ±5V supplies. Maximum DC
specifications include ±1/2LSB INL, ±3/4LSB DNL and
25ppm/°C full scale drift over temperature. Outstanding
AC performance includes 70dB S/(N + D) and 77dB THD
at the Nyquist input frequency of 150kHz.
■
24-Pin Narrow PDIP and SW Packages
■
Variety of Input Ranges:
0V to 5V (LTC1273)
±2.5V (LTC1275)
±5V (LTC1276U)
APPLICATIO S
■
High Speed Data Acquisition
The internal clock is trimmed for 2.7µs maximum conver-
sion time. The clock automatically synchronizes to each
sample command eliminating problems with asynchro-
nous clock noise found in competitive devices. A high
speed parallel interface eases connections to FIFOs, DSPs
and microprocessors.
■
Digital Signal Processing
■
Multiplexed Data Acquisition Systems
■
Audio and Telecom Processing
■
Spectrum Analysis
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
LTBiCMOS is a trademark of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
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TYPICAL APPLICATIO
Effective Bits and Signal to (Noise + Distortion)
vs Input Frequency
Single 5V Supply, 300ksps, 12-Bit Sampling A/D Converter
LTC1273
5V
12
11
10
9
74
68
62
56
50
1
2
24
23
22
21
20
19
18
17
16
15
14
13
ANALOG INPUT
(0V TO 5V)
A
V
V
DD
IN
2.42V
REF
OUTPUT
+
NC
BUSY
CS
0.1µF
V
REF
10µF
NYQUIST
FREQUENCY
+
3
0.1µF
AGND
D11
D10
D9
10µF
4
µP CONTROL
LINES
8
5
RD
7
6
HBEN
NC
6
7
D8
5
8
D7
NC
4
9
D6
D0/8
D1/9
D2/10
D3/11
3
10
11
12
8- OR 12-BIT
PARALLEL BUS
D5
2
D4
1
f
= 300kHz
SAMPLE
DGND
0
10k
100k
1M 2M
INPUT FREQUENCY (Hz)
LTC1273/75/76 • TA02
LTC1273/75/76 • TA01
127356fa
1