MAX1109CUB ,Single-Supply / Low-Power / 2-Channel / Serial 8-Bit ADCsELECTRICAL CHARACTERISTICS—MAX1108(V = +2.7V to +3.6V; unipolar input mode; COM = GND, f = 500kHz, ..
MAX1109CUB ,Single-Supply / Low-Power / 2-Channel / Serial 8-Bit ADCsApplicationsMAX1108EUB -40°C to +85°C 10 µMAXPortable Data LoggingMAX1109CUB 0°C to +70°C 10 µMAXHa ..
MAX1109CUB ,Single-Supply / Low-Power / 2-Channel / Serial 8-Bit ADCsApplicationsMAX1108EUB -40°C to +85°C 10 µMAXPortable Data LoggingMAX1109CUB 0°C to +70°C 10 µMAXHa ..
MAX1109CUB+TG07 ,Single-Supply, Low-Power, 2-Channel, Serial 8-Bit ADCsFeaturesThe MAX1108/MAX1109 low-power, 8-bit, dual-channel,♦ Single Supply: +2.7V to +3.6V (MAX1108 ..
MAX1109EUB ,Single-Supply / Low-Power / 2-Channel / Serial 8-Bit ADCsFeaturesThe MAX1108/MAX1109 low-power, 8-bit, dual-channel,' Single Supply: +2.7V to +3.6V (MAX1108 ..
MAX110ACAP ,Low-Cost, 2-Channel, 【14-Bit Serial ADCsapplications. A fast550µA (MAX110)serial interface simplifies signal routing and opto-isola-640µA ( ..
MAX3444EESA ,15kV ESD-Protected / 60V Fault-Protected / 10Mbps / Fail-Safe RS-485/J1708 Transceivers
MAX3450EEUD+ ,±15kV ESD-Protected USB Transceivers
MAX3454EEUD ,15kV ESD-Protected USB Transceivers
MAX3454EEUD ,15kV ESD-Protected USB Transceivers
MAX3460CSD ,+5V / Fail-Safe / 20Mbps / Profibus RS-485/ RS-422 Transceivers
MAX3462CSA+ ,+5V, Fail-Safe, 20Mbps, PROFIBUS RS-485/RS-422 Transceivers
MAX1108CUB-MAX1109CUB-MAX1109EUB
Single-Supply / Low-Power / 2-Channel / Serial 8-Bit ADCs
General DescriptionThe MAX1108/MAX1109 low-power, 8-bit, dual-channel,
analog-to-digital converters (ADCs) feature an internal
track/hold (T/H) voltage reference, clock, and serial inter-
face. The MAX1108 is specified from +2.7V to +3.6V and
consumes only 105µA. The MAX1109 is specified from
+4.5V to +5.5V and consumes only 130µA. The analog
inputs are software configurable, allowing unipolar/bipolar
and single-ended/differential operation; battery monitor-
ing capability is also included.
The full-scale analog input range is determined by the
internal reference of +2.048V (MAX1108) or +4.096V
(MAX1109), or by an externally applied reference rang-
ing from 1V to VDD. The MAX1108/MAX1109 also feature
a software power-down mode that reduces power con-
sumption to 0.5µA when the device is not in use. The
4-wire serial interface directly connects to SPI™, QSPI™,
and MICROWIRE™ devices without external logic.
Conversions up to 50ksps are performed using either the
internal clock or an external serial-interface clock.
The MAX1108 and MAX1109 are available in a 10-pin
µMAX package with a footprint that is just 20% of an
8-pin plastic DIP.
ApplicationsPortable Data Logging
Hand-Held Measurement Devices
Medical Instruments
System Diagnostics
Solar-Powered Remote Systems
4–20mA-Powered Remote Systems
Receive-Signal Strength Indicators
FeaturesSingle Supply:+2.7V to +3.6V (MAX1108)
+4.5V to +5.5V (MAX1109)Low Power:105µA at +3V and 50ksps
0.5µA in Power-Down ModeSoftware-Configurable Unipolar or Bipolar InputsInput Voltage Range: 0 to VDDInternal Track/HoldInternal Reference:+2.048V (MAX1108)
+4.096V (MAX1109)Reference Input Range: 1V to VDDSPI/QSPI/MICROWIRE-Compatible Serial InterfaceVDDMonitoring ModeSmall 10-Pin µMAX Package
MAX1108/MAX1109
Single-Supply, Low-Power,
2-Channel, Serial 8-Bit ADCs
Functional Diagram19-1399; Rev 0; 10/98
Pin Configuration
Ordering InformationSPI and QSPI are trademarks of Motorola, Inc. MICROWIREis a trademark of National Semiconductor Corp.
MAX1108/MAX1109
Single-Supply, Low-Power,
2-Channel, Serial 8-Bit ADCs
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS—MAX1108(VDD= +2.7V to +3.6V; unipolar input mode; COM = GND, fSCLK= 500kHz, external clock mode (50% duty cycle); 10 clocks/conver-
sion cycle (50ksps); 1µF capacitor at REF, external +2.048V reference at REF; TA= TMINto TMAX; unless otherwise noted. Typical
values are at TA= +25°C.)
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
VDDto GND..............................................................-0.3V to +6V
CH0, CH1, COM, REF, DOUT to GND.......-0.3V to (VDD+ 0.3V)
DIN, SCLK, CSto GND............................................-0.3V to +6V
Continuous Power Dissipation (TA= +70°C)
10-pin µMAX (derate 5.6mW/°C above +70°C)............444mW
Operating Temperature Ranges
MAX110_CUB......................................................0°C to +70°C
MAX110_EUB...................................................-40°C to +85°C
Storage Temperature Range.............................-65°C to +150°C
Lead Temperature (soldering, 10sec).............................+300°C
MAX1108/MAX1109
Single-Supply, Low-Power,
2-Channel, Serial 8-Bit ADCs
ELECTRICAL CHARACTERISTICS—MAX1108 (continued)(VDD= +2.7V to +3.6V; unipolar input mode; COM = GND, fSCLK= 500kHz, external clock mode (50% duty cycle); 10 clocks/conver-
sion cycle (50ksps); 1µF capacitor at REF, external +2.048V reference at REF; TA= TMINto TMAX; unless otherwise noted. Typical
values are at TA= +25°C.)
MAX1108/MAX1109
Single-Supply, Low-Power,
2-Channel, Serial 8-Bit ADCs
ELECTRICAL CHARACTERISTICS—MAX1108 (continued)(VDD= +2.7V to +3.6V; unipolar input mode; COM = GND, fSCLK= 500kHz, external clock mode (50% duty cycle); 10 clocks/conver-
sion cycle (50ksps); 1µF capacitor at REF, external +2.048V reference at REF; TA= TMINto TMAX; unless otherwise noted. Typical
values are at TA= +25°C.)
ELECTRICAL CHARACTERISTICS—MAX1109 (VDD= +4.5V to +5.5V; unipolar input mode; COM = GND, fSCLK= 500kHz, external clock (50% duty cycle); 10 clocks/conversion
cycle (50ksps); 1µF capacitor at REF, external +4.096V reference at REF; TA= TMINto TMAX; unless otherwise noted. Typical values
are at TA= +25°C.)
MAX1108/MAX1109
Single-Supply, Low-Power,
2-Channel, Serial 8-Bit ADCs
ELECTRICAL CHARACTERISTICS—MAX1109 (continued)(VDD= +4.5V to +5.5V; unipolar input mode; COM = GND, fSCLK= 500kHz, external clock (50% duty cycle); 10 clocks/conversion
cycle (50ksps); 1µF capacitor at REF, external +4.096V reference at REF; TA= TMINto TMAX; unless otherwise noted. Typical values
are at TA= +25°C.)
MAX1108/MAX1109
Single-Supply, Low-Power,
2-Channel, Serial 8-Bit ADCs
ELECTRICAL CHARACTERISTICS—MAX1109 (continued)(VDD= +4.5V to +5.5V; unipolar input mode; COM = GND, fSCLK= 500kHz, external clock (50% duty cycle); 10 clocks/conversion
cycle (50ksps); 1µF capacitor at REF, external +4.096V reference at REF; TA= TMINto TMAX; unless otherwise noted. Typical values
are at TA= +25°C.)
MAX1108/MAX1109
Single-Supply, Low-Power,
2-Channel, Serial 8-Bit ADCs
ELECTRICAL CHARACTERISTICS—MAX1109 (continued)(VDD= +4.5V to +5.5V; unipolar input mode; COM = GND, fSCLK= 500kHz, external clock (50% duty cycle); 10 clocks/conversion
cycle (50ksps); 1µF capacitor at REF, external +4.096V reference at REF; TA= TMINto TMAX; unless otherwise noted. Typical values
are at TA= +25°C.)
Note 1:Relative accuracy is the deviation of the analog value at any code from its theoretical value after the full-scale range has
been calibrated.
Note 2:See Typical Operating Characteristics.
Note 3:VREF= +2.048V (MAX1108), VREF= +4.096V (MAX1109), offset nulled.
Note 4:Common-mode range (CH0, CH1, COM) GND to VDD.
Note 5:Conversion time defined as the number of clock cycles times the clock period; clock has 50% duty cycle (Figures 6 and 8).
Note 6:REF supplies typically 2.5mA under normal operating conditions.
Note 7:External load should not change during the conversion for specified accuracy.
Note 8:Power consumption with CMOS levels.
Note 9:Measured as ‰ VFS(2.7V) - VFS(3.6V)‰for MAX1108, and measured as ‰VFS(4.5V) - VFS(5.5V)‰for MAX1109.
Note 10:1µF at REF, internal reference settling to 0.5LSB.
Typical Operating Characteristics(VDD= +3.0V (MAX1108), VDD= +5.0V (MAX1109); external conversion mode; fSCLK= 500kHz; 50ksps; external reference; 1µF at
REF; TA= +25°C; unless otherwise noted.)
MAX1108/MAX1109
Single-Supply, Low-Power,
2-Channel, Serial 8-Bit ADCs
Typical Operating Characteristics (continued)(VDD= +3.0V (MAX1108), VDD= +5.0V (MAX1109); external conversion mode; fSCLK= 500kHz; 50ksps; external reference; 1µF at
REF; TA= +25°C; unless otherwise noted.)
MAX1108/MAX1109
Single-Supply, Low-Power,
2-Channel, Serial 8-Bit ADCs
Typical Operating Characteristics (continued)(VDD= +3.0V (MAX1108), VDD= +5.0V (MAX1109); external conversion mode; fSCLK= 500kHz; 50ksps; external reference; 1µF at
REF; TA= +25°C; unless otherwise noted.)
Pin DescriptionCONVERSION TIME vs. TEMPERATURE
MAX1108/09-16
TEMPERATURE (°C)
CONVERSION TIME (
NORMALIZED REFERENCE VOLTAGE
vs. TEMPERATURE
MAX1108/09-17
TEMPERATURE (°C)
REFERENCE VOLTAGE (V)
CHANNEL-TO-CHANNEL
CROSSTALK vs. FREQUENCY
-20MAX1108/09-18
FREQUENCY (kHz)
CROSSTALK (dB)101520
-60
MAX1108/MAX1109
Single-Supply, Low-Power,
2-Channel, Serial 8-Bit ADCs
_______________Detailed DescriptionThe MAX1108/MAX1109 analog-to-digital converters
(ADCs) use a successive-approximation conversion
technique and input track/hold (T/H) circuitry to convert
an analog signal to an 8-bit digital output. A flexible
serial interface provides easy interface to microproces-
sors (µPs). No external hold capacitors are required. All
of the MAX1108/MAX1109 operating modes are soft-
ware-configurable: internal or external reference, inter-
nal or external conversion clock, single-ended unipolar
or pseudo-differential unipolar/bipolar conversion, and
power down (Table 1).
Analog Inputs
Track/HoldThe input architecture of the ADCs is illustrated in the
equivalent-input circuit of Figure 4 and is composed of
the T/H, the input multiplexer, the input comparator, the
switched capacitor DAC, the reference, and the auto-
zero rail.
The analog-inputs configuration is determined by the
control-byte through the serial interface as shown in
Table 2 (see Modes of Operationsection and Table 1).
The eight modes of operation include single-ended,
pseudo-differential, unipolar/bipolar, and a VDDmoni-
toring mode. During acquisition and conversion, only
one of the switches in Figure 4 is closed at any time.
The T/H enters its tracking mode on the falling clock
edge after bit 4 (SEL0) of the control byte has been
shifted in. It enters its hold mode on the falling edge
after the bit 2 (I/EREF) of the control byte has been
shifted in.
For example, If CH0 and COM are chosen (SEL2 =
SEL1 = SEL0 = 1) for conversion, CH0 is defined as the
sampled input (SI), and COM is defined as the refer-
ence input (RI). During acquisition mode, the CH0
switch and the T/H switch are closed, charging the
Figure 1. Load Circuits for Enable Time
Figure 2. Load Circuits for Disable Time
