MAX11612_11 Datasheet, PDF (9/22 Pages) Maxim Integrated Products – Low-Power, 4-/8-/12-Channel, I2C, 12-Bit ADCs in Ultra-Small Packages

Low-Power, 4-/8-/12-Channel, I²C,
12-Bit ADCs in Ultra-Small Packages
SDA
SCL
INPUT SHIFT REGISTER
V_DD
GND
SETUP REGISTER
CONTROL
LOGIC
INTERNAL
OSCILLATOR
CONFIGURATION REGISTER
AIN0
AIN1
AIN2
AIN3
AIN4
AIN5
AIN6
AIN7
AIN8
AIN9
AIN10
AIN11/REF
ANALOG
INPUT
MUX
T/H
12-BIT
ADC
REF
REFERENCE
4.096V (MAX11616)
2.048V (MAX11617)
OUTPUT SHIFT
REGISTER
AND RAM
MAX11616
MAX11617
Figure 2. MAX11616/MAX11617 Simplified Functional Diagram
V_DD
I_OL
SDA
V_OUT
400pF
I_OH
Figure 3. Load Circuit
Detailed Description
The MAX11612–MAX11617 analog-to-digital converters
(ADCs) use successive-approximation conversion tech-
niques and fully differential input track/hold (T/H) cir-
cuitry to capture and convert an analog signal to a
serial 12-bit digital output. The MAX11612/MAX11613
are 4-channel ADCs, the MAX11614/MAX11615 are
8-channel ADCs, and the MAX11616/MAX11617 are
12-channel ADCs. These devices feature a high-speed,
2-wire serial interface supporting data rates up to
1.7MHz. Figure 2 shows the simplified internal structure
for the MAX11616/MAX11617.
Power Supply
The MAX11612–MAX11617 operate from a single sup-
ply and consume 670µA (typ) at sampling rates up to
94.4ksps. The MAX11613/MAX11615/MAX11617 fea-
ture a 2.048V internal reference and the MAX11612/
MAX11614/MAX11616 feature a 4.096V internal refer-
ence. All devices can be configured for use with an
external reference from 1V to V_DD.
Analog Input and Track/Hold
The MAX11612–MAX11617 analog-input architecture
contains an analog-input multiplexer (mux), a fully dif-
ferential track-and-hold (T/H) capacitor, T/H switches, a
comparator, and a fully differential switched capacitive
digital-to-analog converter (DAC) (Figure 4).
In single-ended mode, the analog input multiplexer con-
nects C_T/H between the analog input selected by
CS[3:0] (see the Configuration/Setup Bytes (Write Cycle)
section) and GND (Table 3). In differential mode, the
analog-input multiplexer connects C_T/H to the + and -
analog inputs selected by CS[3:0] (Table 4).
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