LTC1409
12-Bit, 800ksps Sampling
A/D Converter with Shutdown
U
DESCRIPTIO
FEATURES
s
s
s
s
s
s
s
s
s
s
Sample Rate: 800ksps
Power Dissipation: 80mW
72.5dB S/(N + D) and 86dB THD at Nyquist
No Pipeline Delay
Nap (4mW) and Sleep (10µW) Shutdown Modes
Operates with Internal 15ppm/°C Reference
or External Reference
True Differential Inputs Reject Common Mode Noise
20MHz Full Power Bandwidth Sampling
±2.5V Bipolar Input Range
28-Pin SO Wide and SSOP Package
s
s
s
s
s
s
The LTC1409 full-scale input range is ±2.5V. Maximum
DC specs include ±1LSB INL and ±1LSB DNL over temperature. Outstanding AC performance includes 72.5dB
S/(N + D) 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.
UO
APPLICATI
The LTC ®1409 is a 1µs, 800ksps, sampling 12-bit A/D
converter that draws only 80mW from ±5V supplies. This
easy-to-use device includes a high dynamic range sampleand-hold and a precision reference. Two digitally selectable
power Shutdown modes provide flexibility for low power
systems.
S
Telecommunications
Digital Signal Processing
Multiplexed Data Acquisition Systems
High Speed Data Acquisition
Spectrum Analysis
Imaging Systems
The ADC has a µP compatible, 12-bit parallel output port.
There is no pipeline delay in the conversion results.
A separate convert start input and a data ready signal
(BUSY) ease connections to FIFOs, DSPs and microprocessors. A digital output driver power supply pin allows
direct connection to 3V logic.
, LTC and LT are registered trademarks of Linear Technology Corporation.
UO
TYPICAL APPLICATI
Effective Bits and Signal-to-(Noise + Distortion)
vs Input Frequency
800kHz, 12-Bit Sampling A/D Converter
12
5V
74
28
26
10
–5V
25
10µF
24
23
22
µP CONTROL
LINES
21
62
NYQUIST
FREQUENCY
10µF
EFFECTIVE BITS
27
68
56
8
50
6
4
S/(N + D) (dB)
LTC1409
DIFFERENTIAL 1
AVDD
+AIN
ANALOG INPUT
(–2.5V TO 2.5V) 2
–AIN
OVDD
2.50V 3 V
VSS
VREF OUTPUT 4 REF
REFCOMP
BUSY
5
10µF
AGND
CS
6
D11(MSB) CONVST
7
D10
RD
8
D9
SHDN
9
D8
NAP/SLP
10
D7
OGND
12-BIT
11
D6
D0
PARALLEL
12
BUS
D5
D1
13
D4
D2
14
DGND
D3
20
19
2
18
17
16
15
fSAMPLE = 800ksps
0
1k
10k
100k
1M
INPUT FREQUENCY (Hz)
10M
LTC1409 • TA02
LTC1409 • TA01
1
