MAX1192 Maxim, MAX1192 Datasheet - Page 16

• Manufacturer Part Number: MAX1192
• Description: Ultra-Low-Power / 22Msps / Dual 8-Bit ADC
• Manufacturer: Maxim

Figure 3 displays a simplified functional diagram of the
input T/H circuits. In track mode, switches S1, S2a,
S2b, S4a, S4b, S5a, and S5b are closed. The fully dif-
ferential circuits sample the input signals onto the two
capacitors (C2a and C2b) through switches S4a and
S4b. S2a and S2b set the common mode for the ampli-
Ultra-Low-Power, 22Msps, Dual 8-Bit ADC
Figure 3. Internal T/H Circuits
16
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Input Track-and-Hold (T/H) Circuits
INA+
INA-
INB+
INB-
S4a
S4b
S4a
S4b
S4c
S4c
C2a
C2b
C2a
C2b
INTERNAL
S2a
INTERNAL
INTERNAL
S2a
INTERNAL
BIAS
BIAS
BIAS
BIAS
S1
S1
S2b
S2b
C1a
C1b
C1a
C1b
COM
COM
COM
COM
S5a
S5b
S5a
S5b
S3a
S3b
S3a
S3b
fier input, and open simultaneously with S1, sampling
the input waveform. Switches S4a, S4b, S5a, and S5b
are then opened before switches S3a and S3b connect
capacitors C1a and C1b to the output of the amplifier
and switch S4c is closed. The resulting differential volt-
ages are held on capacitors C2a and C2b. The ampli-
fiers charge capacitors C1a and C1b to the same
OUT
OUT
OUT
OUT
HOLD
TRACK
HOLD
MAX1192
TRACK
CLK
INTERNAL
NONOVERLAPPING
CLOCK SIGNALS