ltc1411 Linear Technology Corporation, ltc1411 Datasheet - Page 7

• Manufacturer Part Number: ltc1411
• Description: Single Supply 14-bit 2.5msps Adc
• Manufacturer: Linear Technology Corporation

TYPICAL CO
PI FU CTIO S
DVP (Pin 30): 5V Digital Power Supply Pin. Bypass to
OGND with a 10 F tantalum capacitor.
DGND (Pin 31): Digital Ground.
CONVST (Pin 32): Conversion Start Signal. This active
low signal starts a conversion on its falling edge.
PGA1, PGA0 (Pins 33, 34): Logic Inputs for Program-
mable Input Range. This ADC has four input ranges (or
four REFCOM2 voltages) controlled by these two pins.
For the logic inputs applied to PGA0 and PGA1, the
following summarizes the gain levels and the analog
input range with A
U
U
+
+
+
22 F*
10 F
10 F
IN
U U
U
–
tied to 2.5V.
1
2
3
4
5
6
*A 22 F CAPACITOR IS NEEDED IF REFOUT IS USED TO DRIVE A
ECTIO DIAGRA
7, 8, 9
REFOUT
REFIN
REFCOM1
REFCOM2
A
A
IN
IN
+
–
AGND
U
5k
5k
X1.62/
X1.15
REFERENCE
BANDGAP
2.5V
2k
11
AVM
36
SLP
35
W
CONTROL LOGIC
NAP
INTERNAL
CLOCK
34
+
–
PGA0
Table 1. Input Spans for LTC1411
NAP (Pin 35): Nap Input. Driving this pin low will put the
ADC in the Nap mode and will reduce the supply current to
2mA and the internal reference will remain active.
SLP (Pin 36): Sleep Input. Driving this pin low will put the
ADC in the Sleep mode and the ADC draws less than 1 A
of supply current.
14-BIT
+
ADC
PGA0
33
10
IN
5V
5V
0V
0V
–
PGA1
AVP
5V
30
32
14
PGA1
CONVST
DVP
5V
0V
5V
0V
DRIVERS
OUTPUT
31
DGND
LEVEL
– 6dB
– 3dB
– 9dB
0dB
OGND
BUSY
OV
OTR
D13
D0
DD
•
•
•
29
28
12
25
27
26
1411 TA01
INPUT
+
SPAN
1.28V
0.64V
1.8V
0.9V
5V OR 3V
LTC1411
REFCOM2
VOLTAGE
1.45V
2.9V
4V
2V
7
1411f