ltc2440cgn-trpbf Linear Technology Corporation, ltc2440cgn-trpbf Datasheet - Page 9

• Manufacturer Part Number: ltc2440cgn-trpbf
• Description: 24-bit High Speed Differential Delta Sigma Adc With Selectable Speed/resolution
• Manufacturer: Linear Technology Corporation

FUNCTIONAL BLOCK DIAGRAM
TEST CIRCUITS
APPLICATIONS INFORMATION
CONVERTER OPERATION
Converter Operation Cycle
The LTC2440 is a high speed, delta-sigma analog-to-digital
converter with an easy to use 4-wire serial interface (see
Figure 1). Its operation is made up of three states. The
converter operating cycle begins with the conversion,
followed by the low power sleep state and ends with the
data output (see Figure 2). The 4-wire interface consists
of serial data input (SDI), serial data output (SDO), serial
clock (SCK) and chip select (CS). The interface, timing,
operation cycle and data out format is compatible with
the LTC2410.
REF
REF
GND
V
IN
IN
CC
+
–
+
–
+
–
SDO
Hi-Z TO V
V
V
1.69k
OL
OH
+
TO V
TO Hi-Z
DAC
–
OH
OH
C
LOAD
2440 TA03
= 20pF
Figure 1. Functional Block Diagram
ADC
Figure 2. LTC2440 State Transition Diagram
2440 F01
SDO
AUTOCALIBRATION
DECIMATING FIR
AND CONTROL
Hi-Z TO V
V
V
OH
OL
FALSE
V
TO Hi-Z
TO V
CC
1.69k
OL
C
OL
DATA OUTPUT
LOAD
CONVERT
CS = LOW
SCK
SLEEP
AND
2440 TA04
= 20pF
TRUE
2440 F02
OSCILLATOR
INTERFACE
INTERNAL
SERIAL
LTC2440
(INT/EXT)
f
SDO
SCK
CS
SDI
BUSY
EXT
O
2440fc
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