MAX1192 Maxim, MAX1192 Datasheet - Page 15

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

Figure 1. Pipeline Architecture—Stage Blocks
Figure 2. MAX1192 Functional Diagram
INA+
INA-
PIN
23
24
25
26
27
—
T/H
FLASH
ADC
Ultra-Low-Power, 22Msps, Dual 8-Bit ADC
NAME
REFIN
REFN
REFP
COM
REFIN
REFN
PD0
REFP
COM
INA+
INB+
INA-
INB-
EP
______________________________________________________________________________________
T/H
STAGE 1
1.5 BITS
DAC
Power-Down Digital Input 0. See Table 3.
Reference Input. Internally pulled up to V
Common-Mode Voltage I/O. Bypass COM to GND with a 0.33µF capacitor.
Negative Reference I/O. Conversion range is ±(V
capacitor.
Positive Reference I/O. Conversion range is ±(V
capacitor.
Exposed Paddle. Internally connected to pin 3. Externally connect EP to GND.
DIGITAL ERROR CORRECTION
T/H
T/H
STAGE 2
+
∑
D0–D7
-
SYSTEM AND
REFERENCE
PIPELINE
PIPELINE
CIRCUITS
ADC
ADC
BIAS
A
B
x2
STAGE 7
/
/
DEC
DEC
MULTIPLEXER
The MAX1192 uses a seven-stage, fully differential,
pipelined architecture (Figure 1) that allows for high-
speed conversion while minimizing power consump-
tion. Samples taken at the inputs move progressively
through the pipeline stages every half-clock cycle.
Including the delay through the output latch, the total
clock-cycle latency is 5 clock cycles for channel A and
5.5 clock cycles for channel B.
At each stage, flash ADCs convert the held input volt-
ages into a digital code. The following digital-to-analog
converter (DAC) converts the digitized result back into
an analog voltage, which is then subtracted from the
original held input signal. The resulting error signal is
then multiplied by two, and the product is passed along
to the next pipeline stage where the process is repeated
until the signal has been processed by all stages. Digital
error correction compensates for ADC comparator off-
sets in each pipeline stage and ensures no missing
codes. Figure 2 shows the MAX1192 functional diagram.
DD
.
FUNCTION
REFP
REFP
MAX1192
Pin Description (continued)
- V
- V
REFN
REFN
). Bypass REFP to GND with a 0.33µF
DRIVERS
OUTPUT
TIMING
). Bypass REFN to GND with a 0.33µF
CONTROL
POWER
Detailed Description
OV
V
GND
PD0
PD1
D0–D7
A/B
OGND
CLK
DD
DD
15