LTC2412
11
2412f
TEST CIRCUITS
FU CTIO AL BLOCK DIAGRA
UU
W
Figure 1. Functional Block Diagram
PI FU CTIO S
UU
U
FO (Pin 14): Frequency Control Pin. Digital input that
controls the ADC’s notch frequencies and conversion
time. When the FO pin is connected to VCC (FO = VCC), the
converter uses its internal oscillator and the digital filter
first null is located at 50Hz. When the FO pin is connected
to GND (FO = OV), the converter uses its internal oscillator
and the digital filter first null is located at 60Hz. When FO
is driven by an external clock signal with a frequency fEOSC,
the converter uses this signal as its system clock and the
digital filter first null is located at a frequency fEOSC/2560.
AUTOCALIBRATION
AND CONTROL
DECIMATING FIR
CH0/CH1
INTERNAL
OSCILLATOR
SERIAL
INTERFACE
PING-PONG
DIFFERENTIAL
3RD ORDER
Σ MODULATOR
+–
MUX
GND
REF+
CH0+
IN+
IN–
CH0–
CH1+
CH1–
REF –
VCC
SCK
SDO
CS
FO
(INT/EXT)
1.69k
SDO
2412 TA03
Hi-Z TO VOH
VOL TO VOH
VOH TO Hi-Z
CLOAD = 20pF
1.69k
SDO
2412 TA04
Hi-Z TO VOL
VOH TO VOL
VOL TO Hi-Z
CLOAD = 20pF
VCC