LTC1409 Datasheet, PDF (1/20 Pages) Linear Technology – 12-Bit, 800ksps Sampling A/D Converter with Shutdown

LTC1409
12-Bit, 800ksps Sampling
A/D Converter with Shutdown
FEATURES
s _{Sample Rate: 800ksps}
s _{Power Dissipation: 80mW}
s _{72.5dB S/(N + D) and 86dB THD at Nyquist}
s _{No Pipeline Delay}
s _{Nap (4mW) and Sleep (10µW) Shutdown Modes}
s _{Operates with Internal 15ppm/°C Reference}
or External Reference
s _{True Differential Inputs Reject Common Mode Noise}
s _{20MHz Full Power Bandwidth Sampling}
s _{±2.5V Bipolar Input Range}
s _{28-Pin SO Wide and SSOP Package}
APPLICATI S
s _{Telecommunications}
s _{Digital Signal Processing}
s _{Multiplexed Data Acquisition Systems}
s _{High Speed Data Acquisition}
s _{Spectrum Analysis}
s _{Imaging Systems}
, LTC and LT are registered trademarks of Linear Technology Corporation.
DESCRIPTIO
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 sample-
and-hold and a precision reference. Two digitally selectable
power Shutdown modes provide flexibility for low power
systems.
The LTC1409 full-scale input range is ±2.5V. Maximum
DC specs include ±1LSB INL and ±1LSB DNL over tem-
perature. 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.
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 micropro-
cessors. A digital output driver power supply pin allows
direct connection to 3V logic.
TYPICAL APPLICATI
800kHz, 12-Bit Sampling A/D Converter
LTC1409
DIFFERENTIAL ₁
28
ANALOG INPUT
(–2.5V TO 2.5V)
2.50V
V_REF OUTPUT
2
3
4
+A_IN
–A_IN
V_REF
AV_{DD 27}
OV_{DD 26}
V_{SS 25}
REFCOMP BUSY
5
24
10µF
AGND
CS
6
23
D11(MSB) CONVST
7
22
D10
RD
8
21
D9
SHDN
9
20
D8
NAP/SLP
10
19
D7
OGND
12-BIT 11
18
PARALLEL
BUS
D6
12
D5
D0
17
D1
13
16
D4
D2
14
15
DGND
D3
5V
– 5V
10µF
10µF
µP CONTROL
LINES
Effective Bits and Signal-to-(Noise + Distortion)
vs Input Frequency
12
74
68
10
NYQUIST
62
FREQUENCY
56
8
50
6
4
2
f_SAMPLE = 800ksps
0
1k
10k
100k
1M
10M
INPUT FREQUENCY (Hz)
LTC1409 • TA02
LTC1409 • TA01
1