CA3310

CA3310 - 10-Bit Successive Approximation Analog-to-Digital Converter (ADC)

Overview

The Intersil CA3310 is a high-performance, low-power, 10-bit successive approximation analog-to-digital converter (ADC) designed for applications requiring fast and accurate signal conversion. This CMOS-based ADC operates on a single supply voltage ranging from 3V to 6V, making it suitable for both portable and embedded systems. With a typical power consumption of just 15mW and a conversion time of 13µs, the CA3310 is ideal for high-speed, low-power applications.

The device features a built-in track-and-hold circuit that ensures accurate sampling of high-bandwidth input signals, even at rail-to-rail voltage levels. Its microprocessor-compatible control lines and latched three-state output drivers simplify integration into digital systems, while the option for internal or external clock operation provides flexibility in timing control.

Features

• Low Power Consumption: Typically 15mW, making it ideal for battery-operated devices.
• Single Supply Operation: Works with a supply voltage range of 3V to 6V.
• Fast Conversion Time: 13µs for 10-bit resolution.
• Built-In Track-and-Hold: Ensures accurate sampling of dynamic input signals.
• Rail-to-Rail Input Range: Accepts signals from ground to supply voltage.
• Microprocessor-Compatible: Features latched three-state output drivers for easy interfacing with digital systems.
• Flexible Clocking: Supports both internal and external clock modes.
• No-Droop Sample-and-Hold: Maintains signal integrity during conversion.

Applications

The CA3310 is well-suited for a variety of applications, including:

• Voice-Grade Digital Audio: Provides high-fidelity analog-to-digital conversion for audio processing.
• DSP Modems: Enables fast signal conversion in digital signal processing applications.
• Remote Low-Power Data Acquisition Systems: Ideal for sensor interfaces in distributed monitoring systems.
• Microprocessor-Controlled Systems: Easily interfaces with microcontrollers and digital logic for embedded applications.
• Industrial Automation: Used in control systems requiring precise analog measurements.
• Medical Instrumentation: Suitable for portable medical devices due to low power consumption.

Electrical Characteristics

The following table summarizes the key electrical specifications of the CA3310:

• Supply Voltage Range: 3V to 6V
• Power Consumption (Typical): 15mW at 5V
• Input Voltage Range: 0V to V_DD (Rail-to-Rail)
• Conversion Time: 13µs (Max)
• Resolution: 10 Bits
• Linearity Error (INL): ±1 LSB (Max)
• Differential Non-Linearity (DNL): ±0.5 LSB (Max)
• Sampling Rate: Up to 76.9 kSPS (Samples Per Second)
• Operating Temperature Range: -40°C to +85°C

Package Information

The CA3310 is available in multiple package options to accommodate different PCB layouts and assembly requirements. The following packages are commonly available:

• 20-Pin Plastic Dual In-Line Package (PDIP): Suitable for through-hole mounting.
• 20-Pin Small Outline Integrated Circuit (SOIC): Ideal for space-constrained applications.
• 20-Pin Ceramic Dual In-Line Package (CERDIP): Provides enhanced thermal and mechanical stability for harsh environments.

Pin Configuration: The device includes dedicated pins for analog input, reference voltage, digital outputs, and control signals. A detailed pinout diagram is provided in the datasheet.

Functional Description

The CA3310 operates on the successive approximation register (SAR) principle, where the analog input is compared against a digitally generated voltage in a step-by-step manner to determine the 10-bit digital output. The built-in track-and-hold circuit captures the input signal at the start of conversion and holds it steady during the conversion process, ensuring accuracy even for rapidly changing signals.

The device features a three-state output buffer, allowing multiple ADCs to share a common data bus in microprocessor-based systems. Control signals such as Chip Select (CS), Read (RD), and Convert Start (CONV) facilitate seamless integration with digital logic.

Design Considerations

When designing with the CA3310, consider the following:

• Power Supply Decoupling: Use a 0.1µF ceramic capacitor close to the V_DD pin to minimize noise.
• Reference Voltage: For optimal performance, ensure a stable reference voltage is applied to the V_REF pin.
• Clock Source: The internal clock is sufficient for most applications, but an external clock can be used for synchronization.
• PCB Layout: Keep analog and digital traces separate to reduce noise coupling.

Conclusion

The Intersil CA3310 is a versatile, high-performance 10-bit ADC that combines low power consumption with fast conversion times. Its rail-to-rail input range, built-in track-and-hold, and microprocessor compatibility make it an excellent choice for a wide range of applications, from audio processing to industrial control systems. With multiple package options and robust electrical characteristics, the CA3310 is a reliable solution for designers seeking precision and efficiency in analog-to-digital conversion.