ltc2428 Linear Technology Corporation, ltc2428 Datasheet - Page 9

• Manufacturer Part Number: ltc2428
• Description: 4-/8-channel 20-bit ?power No Latency Delta-sigma Adc
• Manufacturer: Linear Technology Corporation

PIN
GND (Pins 1, 6, 16, 18, 22, 27, 28): Ground. Should be
connected directly to a ground plane through a minimum
length trace or it should be the single-point-ground in a
single-point grounding system.
V
5.5V. Bypass to GND with a 10 F tantalum capacitor in
parallel with 0.1 F ceramic capacitor as close to the part
as possible.
FS
full-scale input value. When V
full scale (FFFFF
FS
ADCIN (Pin 4): Analog Input. The input voltage range is
– 0.125 • V
voltage range may be limited by the pin absolute maxi-
mum rating of – 0.3V to V
ZS
zero-scale input value. When V
zero scale (00000
LTC2408 this pin must be grounded.
MUXOUT (Pin 7): MUX Output. This pin is the output of the
multiplexer. Tie to ADCIN for normal operation.
CH0 (Pin 9): Analog Multiplexer Input.
TYPICAL PERFOR A CE CHARACTERISTICS
CC
SET
SET
SET
12
U
20
18
16
14
10
(Pins 2, 8): Positive Supply Voltage. 2.7V
0
INL vs Output Rate
V
V
F
– ZS
(Pin 3): Full-Scale Set Input. This pin defines the
(Pin 5): Zero-Scale Set Input. This pin defines the
FUNCTIONS
O
CC
REF
10 20 30
= EXTERNAL
= 5V
= 5V
U
REF
SET
T
A
.
OUTPUT RATE (Hz)
= –45 C
to 1.125 • V
H
T
40
H
A
). The total reference voltage (V
). For pin compatibility with the LTC2404/
= 25 C
50 60 70 80 90 100
U
CC
REF
T
A
W
= 90 C
+ 0.3V.
IN
. For V
IN
24248 G27
= FS
= ZS
U
SET
SET
REF
, the ADC outputs
, the ADC outputs
> 2.5V the input
20
18
16
14
12
10
0
INL vs Output Rate
V
V
F
T
O
CC
REF
A
10 20 30
= EXTERNAL
= 25 C
= 3V
T
REF
= 2.5V
V
A
= –45 C
CC
) is
OUTPUT RATE (Hz)
40
50 60 70 80 90 100
CH1 (Pin 10): Analog Multiplexer Input.
CH2 (Pin 11): Analog Multiplexer Input.
CH3 (Pin 12): Analog Multiplexer Input.
CH4 (Pin 13): Analog Multiplexer Input. No connect on the
LTC2424.
CH5 (Pin 14): Analog Multiplexer Input. No connect on the
LTC2424.
CH6 (Pin 15): Analog Multiplexer Input. No connect on the
LTC2424.
CH7 (Pin 17): Analog Multiplexer Input. No connect on the
LTC2424.
CLK (Pin 19): Shift Clock for Data In. This clock synchro-
nizes the serial data transfer into the MUX. For normal
operation, drive this pin in parallel with SCK.
CSMUX (Pin 20): MUX Chip Select Input. A logic high on
this input allows the MUX to receive a channel address. A
logic low enables the selected MUX channel and connects
it to the MUXOUT pin for A/D conversion. For normal
operation, drive this pin in parallel with CSADC.
D
is shifted into this input on the last four rising CLK edges
before CSMUX goes low.
IN
(Pin 21): Digital Data Input. The multiplexer address
T
A
= 90 C
24248 G28
LTC2424/LTC2428
24
22
20
18
16
0 7.5
Resolution vs Output Rate
V
V
f
O
CC
REF
= EXTERNAL
= 5V
= 5V
25
OUTPUT RATE (Hz)
50
75
T
T
T
A
A
A
= 25 C
= 90 C
= –45 C
24248 G29
9
100