MAX1202BEAP+ Maxim Integrated Products, MAX1202BEAP+ Datasheet - Page 10

• Manufacturer Part Number: MAX1202BEAP+
• Description: IC ADC 12BIT 8CH 20-SSOP
• Manufacturer: Maxim Integrated Products

Specifications of MAX1202BEAP+

• Number Of Bits: 12
• Sampling Rate (per Second): 133k
• Data Interface: MICROWIRE™, Serial, SPI™
• Number Of Converters: 1
• Power Dissipation (max): 640mW
• Voltage Supply Source: Dual ±
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 20-SSOP
• Number Of Adc Inputs: 8
• Architecture: SAR
• Conversion Rate: 133 KSPs
• Resolution: 12 bit
• Input Type: Voltage
• Interface Type: Serial
• Voltage Reference: Internal 4.096 V or External
• Supply Voltage (max): 5 V
• Maximum Power Dissipation: 640 mW
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Input Voltage: 4.096 V
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The T/H enters tracking mode on the falling clock edge
after the fifth bit of the 8-bit control word is shifted in. The
T/H enters hold mode on the falling clock edge after the
eighth bit of the control word is shifted in. IN- is con-
nected to GND if the converter is set up for single-ended
inputs, and the converter samples the “+” input. IN- con-
nects to the “-” input if the converter is set up for differen-
tial inputs, and the difference of |N+ - IN- is sampled.
The positive input connects back to IN+, at the end of
the conversion, and C
The time required for the T/H to acquire an input signal
is a function of how quickly its input capacitance is
charged. If the input signal’s source impedance is high,
acquisition time increases and more time must be
allowed between conversions. The acquisition time,
t
the signal, and is also the minimum time needed for the
signal to be acquired. It is calculated by the following:
where R
input signal, and t
impedances below 1k
ADC’s AC performance. Higher source impedances can
5V, 8-Channel, Serial, 12-Bit ADCs
with 3V Digital Interface
Figure 5. Quick-Look Circuit
10
ACQ
**REQUIRED FOR MAX1203 ONLY.
*FULL-SCALE ANALOG INPUT, CONVERSION RESULT = $FFF (HEX).
0.01µF
, is the maximum time the device takes to acquire
______________________________________________________________________________________
C2
ANALOG
4.096V
INPUT
0V TO
IN
+3V
= 9kΩ, R
0.01µF
0.1µF
t
ACQ
C1
4.7µF
ACQ
= 9 x (R
S
HOLD
= the source impedance of the
is never less than 1.5µs. Source
REF
VL
CH7
REFADJ
+2.5V
do not significantly affect the
S
charges to the input signal.
+ R
MAX1202
MAX1203
REFERENCE
+2.5V
IN
) x 16pF
**
SSTRB
SHDN
SCLK
DOUT
GND
V
Track/Hold
V
DIN
CS
DD
SS
N.C.
0.1µF
+3V
be used if an input capacitor is connected to the analog
inputs, as shown in Figure 5. Note that the input capaci-
tor forms an RC filter with the input source impedance,
limiting the ADC’s signal bandwidth.
Figure 4. Equivalent Input Circuit
4.7µF
SINGLE-ENDED MODE: IN+ = CHO–CH7, IN- = GND.
DIFFERENTIAL MODE:
GND
OSCILLATOR
CH0
CH1
CH2
CH3
CH6
CH4
CH5
CH7
+5V
2MHz
REF
INPUT
MUX
12-BIT CAPACITIVE DAC
C
SWITCH
IN+ AND IN- SELECTED FROM PAIRS OF
–
CH0/CH1, CH2/CH3, CH4/CH5, CH6/CH7.
C
16pF
CH1
HOLD
TRACK
SWITCH
+
T/H
OSCILLOSCOPE
9k
R
CH2
IN
HOLD
ZERO
CH3
AT THE SAMPLING INSTANT,
THE MUX INPUT SWITCHES
FROM THE SELECTED IN+
CHANNEL TO THE SELECTED
IN- CHANNEL.
COMPARATOR
CH4
SSTRB
SCLK
DOUT*