Analog Devices

The AD7276 /AD7277/AD7278is a 12-bit, high speed, low power, successive approximation analog-to-digital converters (ADCs). The parts operate from a single 2.35 V to 3.6 V power supply and feature throughput rates of up to 3 MSPS. The parts contain a low noise, wide bandwidth track-and-hold amplifier that can handle input frequencies in excess of 55 MHz.The conversion process and data acquisition are controlled usingCSand the serial clock, allowing the devices to interface with microprocessors or DSPs. The input signal is sampled on the falling edge ofCS, and the conversion is also initiated at this point. There are no pipeline delays associated with the part.The AD7276 / AD7277 / AD7278 uses advanced design techniques to achieve very low power dissipation at high throughput rates.The reference for the part is taken internally from VDD. This allows the widest dynamic input range to the ADC; therefore, the analog input range for the part is 0 to VDD. The conversion rate is determined by the SCLKPRODUCT HIGHLIGHTS3 MSPS ADCs in a 6-lead TSOT packageAD7276 / AD7277 / AD7278 andAD7476A/AD7477A/AD7478Apin-compatibleHigh throughput with low power consumptionFlexible power/serial clock speed management. This allows maximum power efficiency at low throughput ratesReference derived from the power supplyNo pipeline delay. The parts feature a standard successive approximation ADC with accurate control of the sampling instant via aCSinput and once-off conversion control.

TheAD7276/AD7277/ AD7278 are 12-/10-/8-bit, high speed, low power, successive approximation analog-to-digital converters (ADCs), respectively. The parts operate from a single 2.35 V to 3.6 V power supply and feature throughput rates of up to 3 MSPS. The parts contain a low noise, wide bandwidth trackand-hold amplifier that can handle input frequencies in excess of 55 MHz.The conversion process and data acquisition are controlled using CS and the serial clock, allowing the devices to interface with microprocessors or DSPs. The input signal is sampled on the falling edge of CS, and the conversion is initiated at this point. There are no pipeline delays associated with the part.The AD7276/AD7277/AD7278 use advanced design techniques to achieve very low power dissipation at high throughput rates. The reference for the part is taken internally from VDD. This allows the widest dynamic input range to the ADC; therefore, the analog input range for the part is 0 to VDD. The conversion rate is determined by the SCLK.PRODUCT HIGHLIGHTS3 MSPS ADCs in a 6-lead TSOT packageAD7476/AD7477/AD7478 and AD7476A/AD7477A/ AD7478A pin-compatibleHigh throughput with low power consumptionFlexible power/serial clock speed management. This allows maximum power efficiency at low throughput ratesReference derived from the power supplyNo pipeline delay. The parts feature a standard successive approximation ADC with accurate control of the sampling instant via aCSinput and once-off conversion control.

The AD7280A contains all the functions required for general-purpose monitoring of stacked lithium ion batteries as used in hybrid electric vehicles, battery backup applications, and power tools. The part has multiplexed cell voltage and auxiliary ADC measurement channels for up to six cells of battery management. An internal ±3 ppm reference is provided that allows a cell voltage accuracy of ±1.6 mV. The ADC resolution is 12 bits and allows conversion of up to 48 cells within 7 μs.The AD7280A operates from just one VDDsupply that has a range of 8 V to 30 V (with an absolute maximum rating of 33 V). The part provides six differential analog input channels to accommodate large common-mode signals across the full VDDrange. Each channel allows an input signal range, VIN(+) − VIN(−), of 1 V to 5 V. The input pins assume a series stack of six cells. In addition, the part includes six auxiliary ADC input channels that can be used for temperature measurement or system diagnostics.The AD7280A includes on-chip registers that allow a sequence of channel measurements to be programmed to suit the applications requirements.The AD7280A also includes a dynamic alert function that can detect if the cell voltages or auxiliary ADC inputs exceed an upper or lower limit defined by the user. The AD7280A has cell balancing interface outputs designed to control external FET transistors to allow discharging of individual cells.The AD7280A includes a built in self-test feature that internally applies a known voltage to the ADC inputs.There is a daisy-chain interface that allows up to eight parts to be stacked without the need for individual device isolation.The AD7280A requires only one supply pin that takes 6.5 mA under normal operation, while converting at 1 MSPS.All this functionality is provided in a 48-lead LQFP package operating over a temperature range of −40°C to +105°C.APPLICATIONSLithium ion battery monitoringElectric and hybrid electric vehiclesPower supply back upPower tools

The AD7284 contains all the functions required for the general-purpose monitoring of stacked Li-Ion batteries, as used in hybrid electric vehicles and battery backup applications.The AD7284 has multiplexed cell voltage and auxiliary, analog-to-digital converter (ADC) measurement channels supporting four to eight cells of battery management. The device provides a maximum total unadjusted error, TUE, (cell voltage accuracy) of ±3 mV that includes all the internal errors from input to output. The primary ADC resolution is 14 bits.The AD7284 also includes an integrated secondary measurement path that validates the data on the primary ADC. Other diagnostic features include the detection of open inputs, communication, and power supply related faults.The AD7284 cell balancing interface outputs control the external field effect transistors (FETs) to allow discharging of individual cells.There are two on-chip 2.5 V voltage references: one reference for the primary measurement path, and one for the secondary measurement path.The AD7284 operates from one VDDsupply, ranging from 10 V to 40 V. The device provides eight differential analog input channels to accommodate large common-mode signals across the full VDDrange. Each channel allows an input signal range, VPINx − VPIN(x − 1) and VSINx – VSIN(x − 1), of 0 V to 5 V, where x = 0 to 8. The input pins assume a series stack of eight cells. The AD7284 includes four auxiliary ADC input channels that can be used for temperature measurement or system diagnostics.The AD7284 has a differential daisy-chain interface that allows multiple devices to be stacked without the need for individual device isolation. By design, this interface allows both device to device communication within the same module and communication between devices on different modules.ApplicationsLi-Ion battery monitoringElectric and hybrid electric vehiclesStationary power applications

The AD7291 is a 12-bit, low power, 8-channel, successive approximation analog-to-digital converter (ADC) with an internal temperature sensor.The part operates from a single 3.3 V power supply and features an I2C-compatible interface. The part contains a 9-channel multiplexer and a track-and-hold amplifier than can handle frequencies up to 30 MHz. The device has an on-chip 2.5 V reference that can be disabled to allow the use of an external reference.The AD7291 provides a 2-wire serial interface compatible with I2C interfaces. The I2C interface supports standard and fast I2C interface modes. The AD7291 normally remains in a partial power-down state while not converting and powers up for conversions. The conversion process can be controlled by a command mode where conversions occur across I2C write operations or an autocycle mode selected through software control.The AD7291 includes a high accuracy band gap temperature sensor, which is monitored and digitized by the 12-bit ADC to give a resolution of 0.25°C.The AD7291 offers a programmable sequencer, which enables the selection of a preprogrammable sequence of channels for conversion.On-chip limit registers can be programmed with high and low limits for the conversion results; an out-of-range indicator output (ALERT) becomes active when the programmed high or low limits are violated by the conversion result. This output can be used as an interrupt.Product HighlightsIdeally suited to monitoring system variables in a variety of systems including telecommunications, process control, and industrial control.I2C-compatible serial interface. Standard and fast modes.Automatic partial power-down while not converting to maximize power efficiency.Channel sequencer operation.Integrated temperature sensor with 0.25°C resolution.Out of range indicator that can be software disabled or enabled.

The AD7293 is a PA drain current controller containing functionality for general-purpose monitoring and control of current, voltage, and temperature, integrated into a single chip solution with an SPI-compatible interface.The device features a 4-channel, 12-bit successive approximation register (SAR) ADC, eight 12-bit DACs (four bipolar and four unipolar with output ranges that can be configured to shut down under external pin control), a ±1.25°C accurate internal temperature sensor, and eight general-purpose input/output (GPIO) pins.The device also includes limit registers for alert functions and four high-side current sense amplifiers to measure current across external shunt resistors. These amplifiers can be optionally set to operate as part of four independent closed-loop drain current controllers.A high accuracy 2.5 V internal reference is provided to drive the DACs and the ADC. The 12-bit ADC monitors and digitizes the internal temperature sensor, and two inputs are included for the external diode temperature sensors.Product HighlightsFour independent closed-loop drain current controllers.Built-in monitoring, sequencing, and alert features.Compatible with both depletion mode and enhancement mode power amplifiers.ApplicationsGaN and GaAs power amplifier monitoring and controlsBase station power amplifiersGeneral-purpose system monitoring and controls

The AD7302 is a dual, 8-bit voltage out DAC that operates from a single +2.7 V to +5.5 V supply. Its on-chip precision output buffers allow the DAC outputs to swing rail to rail. The AD7302 has a parallel microprocessor and DSP-compatible interface with high speed registers and double buffered interface logic. Data is loaded to the registers on the rising edge ofCSorWRand theA/B pin selects either DAC A or DAC B.Reference selection for AD7302 can be either an internal reference derived from the VDDor an external reference applied at the REFIN pin. Both DACs can be simultaneously updated using the asynchronousLDACinput and can be cleared by using the asynchronousCLRinput.The low power consumption of this part makes it ideally suited to portable battery operated equipment. The power consumption is less than 10 mW at 3.3 V, reducing to 3 µW in powerdown mode.The AD7302 is available in a 20-pin plastic dual-in-line package, 20-lead SOIC and a 20-lead TSSOP package.APPLICATIONSPortable Battery Powered InstrumentsDigital Gain and Offset AdjustmentProgrammable Voltage and Current SourcesProgrammable AttenuatorsPRODUCT HIGHLIGHTSLow Power, Single Supply Operation. This part operates from a single +2.7 V to +5.5 V supply and typically consumes 15 mW at 5 V, making it ideal for battery powered applications.The on-chip output buffer amplifiers allow the outputs of the DACs to swing rail to rail with a settling time of typically 1.2 µs.Internal or external reference capability.High speed parallel interface.Power-Down Capability. When powered down the DAC consumes less than 1 µA at 25°C.Packaged in 20-lead DIP, SOIC and TSSOP packages.