LTC1287 LINER [Linear Technology], LTC1287 Datasheet - Page 5

• Manufacturer Part Number: LTC1287
• Description: 3V Single Chip 12-Bit Data Acquisition System
• Manufacturer: LINER [Linear Technology]

PI FU CTIO S
TYPICAL PERFOR
*
**
#
1
2, 3
4
5
6
7
8
500
400
300
200
100
100
10
U
MAXIMUM CLK FREQUENCY REPRESENTS THE CLK FREQUENCY AT WHICH A 0.1LSB
SHIFT IN THE ERROR AT ANY CODE TRANSITION FROM ITS 500kHz VALUE IS FIRST
DETECTED.
AS THE CLK FREQUENCY IS DECREASED FROM 1MHz, MINIMUM CLK FREQUENCY
( ERROR 0.1LSB) REPRESENTS THE FREQUENCY AT WHICH A 0.1LSB SHIFT IN ANY
CODE TRANSITION FROM ITS 500kHz VALUE IS FIRST DETECTED.
0
1
100
100
Maximum Clock Rate vs Source
Resistance
Sample-and-Hold Acquisition
Time vs Source Resistance
PIN
CS
+IN, –IN
GND
V
D
CLK
V
V
V
T
0V TO 2.5V INPUT STEP
V
REF
CC
A
R
REF
CC
OUT
IN
SOURCE
+V
= 25°C
= 3V
R
= 2.5V
IN
SOURCE
U
–
+IN
–IN
1k
+
R
+
–
R
FUNCTION
Chip Select Input
Analog Inputs
Analog Ground
Reference Input
Digital Data Output
Shift Clock
Positive Supply
SOURCE
SOURCE
1k
U
– ( )
+ ( )
10k
V
V
CLK = 500kHz
CC
REF
= 3V
W
= 2.5V
LTC1287 G13
A
LTC G10
100k
U
10k
This clock synchronizes the serial data transfer.
DESCRIPTION
A logic low on this input enables the LTC1287.
These inputs must be free of noise with respect to GND.
GND should be tied directly to an analog ground plane.
The reference input defines the span of the A/D converter and must be kept free of noise with respect to GND.
The A/D conversion result is shifted out of this output.
This supply must be kept free of noise and ripple by bypassing directly to the analog ground plane.
CE
C
1000
0.25
0.05
0.20
0.15
0.10
HARA TERISTICS
600
900
800
700
500
400
300
200
100
0
–50
–50
Minimum Clock Rate for 0.1LSB
Error**
Input Channel Leakage Current vs
Temperature
V
–30
CC
–25
= 3V
AMBIENT TEMPERATURE (°C)
–10
AMBIENT TEMPERATURE (°C)
C
10
0
30
25
OFF CHANNEL
*** MAXIMUM R
50
CHANGE IN FULL SCALE ERROR FROM ITS VALUE AT R
DETECTED.
ON CHANNEL
GUARANTEED
50
70
90 110
75
LTC1287 G11
LTC1287 G14
FILTER
100
130
REPRESENTS THE FILTER RESISTOR VALUE AT WHICH A 0.1LSB
10k
100
1.0
0.8
0.7
0.6
0.4
0.9
0.5
0.3
0.2
0.1
1k
10
1
0
10
Maximum Filter Resistor vs Cycle
Time
0
Noise Error vs Reference Voltage
LTC1287 NOISE = 200 V
C
FILTER
0.5
V
IN
REFERENCE VOLTAGE (V)
R
FILTER
1 F
100
1.0
CYCLE TIME ( s)
FILTER
1.5
+
–
= 0 IS FIRST
LTC1287
P-P
1000
2.0
LTC1287 G12
2.5
LTC1287 G15
5
10000
3.0