September 2007
ADCS7476/ADCS7477/ADCS7478
1MSPS, 12-/10-/8-Bit A/D Converters in SOT-23 & LLP
General Description
Features
The ADCS7476, ADCS7477, and ADCS7478 are low power,
monolithic CMOS 12-, 10- and 8-bit analog-to-digital convert-
ers that operate at 1 MSPS. The ADCS7476/77/78 are drop-
in replacements for Analog Devices' AD7476/77/78. Each
device is based on a successive approximation register ar-
chitecture with internal track-and-hold. The serial interface is
compatible with several standards, such as SPI™, QSPI™,
MICROWIRE™, and many common DSP serial interfaces.
Variable power management
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Packaged in 6-lead, SOT-23 and LLP
Power supply used as reference
Single +2.7V to +5.25V supply operation
SPI™/QSPI™/MICROWIRE™/DSP compatible
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Key Specifications
The ADCS7476/77/78 uses the supply voltage as a refer-
ence, enabling the devices to operate with a full-scale input
range of 0 to VDD. The conversion rate is determined from the
serial clock (SCLK) speed. These converters offer a shut-
down mode, which can be used to trade throughput for power
consumption. The ADCS7476/77/78 is operated with a single
supply that can range from +2.7V to +5.25V. Normal power
consumption during continuous conversion, using a +3V or
+5V supply, is 2 mW or 10 mW respectively. The power down
feature, which is enabled by a chip select (CS) pin, reduces
the power consumption to under 5 µW using a +5V supply. All
three converters are available in a 6-lead, SOT-23 package
and in a 6-lead LLP, both of which provide an extremely small
footprint for applications where space is a critical considera-
tion. These products are designed for operation over the
automotive/extended industrial temperature range of −40°C
to +125°C.
Resolution with no Missing Codes
Conversion Rate
DNL
INL
12/10/8 bits
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1 MSPS
+0.5, -0.3 LSB (typ)
± 0.4 LSB (typ)
Power Consumption
3V Supply
5V Supply
2 mW (typ)
10 mW (typ)
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Applications
Automotive Navigation
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FA/ATM Equipment
Portable Systems
Medical Instruments
Mobile Communications
Instrumentation and Control Systems
Connection Diagram
20057701
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