The ADP1870 / ADP1871?are versatile current-mode, synchronous step-down controllers that provide superior transient response, optimal stability, and current-limit protection by using a constant on-time, pseudo-fixed frequency with a programmable current limit, current-control scheme. In addition, these devices offer optimum performance at low duty cycles by utilizing valley current-mode control architecture. This allows the ADP1870 / ADP1871 to drive all N-channel power stages to regulate output voltages as low as 0.6 V.The ADP1871 is the power saving mode (PSM) version of the device and is capable of pulse skipping to maintain output regulation while achieving improved system efficiency at light loads (see the Power Saving Mode (PSM) Version (ADP1871) section for more information).Available in three frequency options (300 kHz, 600 kHz, and 1.0 MHz, plus the PSM option), the ADP1870 / ADP1871 are well suited for a wide range of applications that require a single-input power supply range from 2.95 V to 20 V. Low voltage biasing is supplied via a 5 V internal LDO.In addition, an internally fixed soft start period is included to limit input in-rush current from the input supply during startup and to provide reverse current protection during soft start for a precharged output. The low-side current-sense, current-gain scheme and integration of a boost diode, along with the PSM/forced pulse width modulation (PWM) option, reduce the external part count and improve efficiency.The ADP1870 / ADP1871 operate over the -40?C to +125?C junction temperature range and are available in 10-lead MSOP package.

The ADP1872?/ ADP1873 are versatile current-mode, synchronous step-down controllers that provide superior transient response, optimal stability, and current limit protection by using a constant on-time, pseudo-fixed frequency with a programmable current-sense gain, current-control scheme. In addition, these devices offer optimum performance at low duty cycles by utilizing valley current-mode control architecture. This allows the ADP1872 /ADP1873 to drive all N-channel power stages to regulate output voltages as low as 0.6 V.The ADP1873 is the power-saving mode (PSM) version of the device and is capable of pulse skipping to maintain output regulation while achieving improved system efficiency at light loads.Available in three frequency options (300 kHz, 600 kHz, and 1.0 MHz), the ADP1872 / ADP1873 are well suited for a wide range of applications. These ICs not only operate from a 2.75 V to 5.5 V bias supply, but also can accept a power input as high as 20 V.In addition, an internally fixed soft start period is included to limit input in-rush current from the input supply during startup and to provide reverse current protection during soft start for a pre-charged output. The low-side current-sense, current-gain scheme, along with the PSM/forced pulse-width modulation (PWM) option, reduces the external part count and improves efficiency. The ADP1872 / ADP1873 operate over the ?40?C to +125?C junction temperature range and are available in a 10-lead MSOP.APPLICATIONS Telecom and networking systems Mid to High End servers Set-top boxes DSP core power supplies

The ADP1882?/ ADP1883 are versatile current-mode, synchronous step-down controllers that provide superior transient response, optimal stability, and current-limit protection by using a constant on-time, pseudo-fixed frequency with a programmable current-limit, current-control scheme. In addition, these devices offer optimum performance at low duty cycles by using valley current-mode control architecture. This allows the ADP1882 / ADP1883 to drive all N-channel power stages to regulate output voltages as low as 0.8 V.The ADP1883 is the power saving mode (PSM) version of the device and is capable of pulse skipping to maintain output regulation while achieving improved system efficiency at light loads (see the Power Saving Mode (PSM) Version (ADP1883) section for more information).Available in three frequency options (300 kHz, 600 kHz, and 1.0 MHz, plus the PSM option), the ADP1882/ADP1883 are well suited for a wide range of applications. These ICs not only operate from a 2.75 V to 5.5 V bias supply, but they also can accept a power input as high as 20 V.In addition, an internally fixed soft start period is included to limit input in-rush current from the input supply during startup and to provide reverse current protection during soft start for a pre-charged output. The low-side current-sense, current-gain scheme and integration of a boost diode, along with the PSM/forced pulse-width modulation (PWM) option, reduce the external part count and improve efficiency.The ADP1882 / ADP1883 operate over the -40?C to +125?C junction temperature range and are available in a 10-lead MSOP.

The ADP1882?/ ADP1883 are versatile current-mode, synchronous step-down controllers that provide superior transient response, optimal stability, and current-limit protection by using a constant on-time, pseudo-fixed frequency with a programmable current-limit, current-control scheme. In addition, these devices offer optimum performance at low duty cycles by using valley current-mode control architecture. This allows the ADP1882 / ADP1883 to drive all N-channel power stages to regulate output voltages as low as 0.8 V.The ADP1883 is the power saving mode (PSM) version of the device and is capable of pulse skipping to maintain output regulation while achieving improved system efficiency at light loads (see the Power Saving Mode (PSM) Version (ADP1883) section for more information).Available in three frequency options (300 kHz, 600 kHz, and 1.0 MHz, plus the PSM option), the ADP1882/ADP1883 are well suited for a wide range of applications. These ICs not only operate from a 2.75 V to 5.5 V bias supply, but they also can accept a power input as high as 20 V.In addition, an internally fixed soft start period is included to limit input in-rush current from the input supply during startup and to provide reverse current protection during soft start for a pre-charged output. The low-side current-sense, current-gain scheme and integration of a boost diode, along with the PSM/forced pulse-width modulation (PWM) option, reduce the external part count and improve efficiency.The ADP1882 / ADP1883 operate over the -40?C to +125?C junction temperature range and are available in a 10-lead MSOP.

The ADP197 is a high-side load switch designed for operation between 1.8 V and 5.5 V. This load switch provides power domain isolation, helping extended power domain isolation. The device contains a low on-resistance, N-channel MOSFET that supports more than 3 A of continuous current and minimizes power loss. The low 18 ?A quiescent current and ultralow shutdown current make the ADP197 ideal for battery-operated portable equipment. The built-in level shifter for enable logic makes the ADP197 compatible with many processors and GPIO controllers.Overtemperature protection circuitry activates if the junction temperature exceeds 125?C, thereby protecting itself and downstream circuits from potential damage.In addition to operating performance, the ADP197 occupies minimal printed circuit board (PCB) space with an area of less than 1.5 mm2 and a height of 0.60 mm.The ADP197 is available in an ultrasmall, 1 mm ? 1.5 mm, 6-ball, 0.5 mm pitch WLCSP.

The ADP2105 / ADP2106 / ADP2107 are low quiescent current,synchronous, step-down dc-to-dc converters in a compact 4 mm ?4 mm LFCSP package. At medium to high load currents, thesedevices use a current mode, constant frequency pulse-widthmodulation (PWM) control scheme for excellent stability andtransient response. To ensure the longest battery life in portableapplications, the ADP2105 / ADP2106 / ADP2107 use a pulsefrequency modulation (PFM) control scheme under light loadconditions that reduces switching frequency to save power.The ADP2105 / ADP2106 / ADP2107 run from input voltages of2.7 V to 5.5 V, allowing single Li+/Li? polymer cell, multiplealkaline/NiMH cells, PCMCIA, and other standard power sources.The output voltage of ADP2105 / ADP2106 / ADP2107 is adjustablefrom 0.8 V to the input voltage (indicated by ADJ), whereas theADP2105 / ADP2106 / ADP2107 are available in preset outputvoltage options of 3.3 V, 1.8 V, 1.5 V, and 1.2 V (indicated by x.x V).Each of these variations is available in three maximum currentlevels: 1 A (ADP2105), 1.5 A (ADP2106), and 2 A (ADP2107).The power switch and synchronous rectifier are integrated forminimal external part count and high efficiency. During logiccontrolled shutdown, the input is disconnected from the output,and it draws less than 0.1 ?A from the input source. Other keyfeatures include undervoltage lockout to prevent deep batterydischarge and programmable soft start to limit inrush current atstartup.Applications Mobile handsets PDAs and palmtop computers Telecommunication/networking equipment Set top boxes Audio/video consumer electronics

The ADP2108 is a high efficiency, low quiescent current step-down dc-to-dc converter manufactured in two different packages. The total solution requires only three tiny external components. It uses a proprietary, high speed current mode, constant frequency PWM control scheme for excellent stability and transient response. To ensure the longest battery life in portable applications, the ADP2108 has a power save mode that reduces the switching frequency under light load conditions.The ADP2108 runs on input voltages of 2.3 V to 5.5 V, which allows for single lithium or lithium polymer cell, multiple alkaline or NiMH cell, PCMCIA, USB, and other standard power sources. The maximum load current of 600 mA is achievable across the input voltage range.The ADP2108 is available in fixed output voltages of 3.3 V, 3.0 V, 2.5 V, 2.3 V, 1.82 V, 1.8 V, 1.5 V, 1.3 V, 1.2 V, 1.1 V, and 1.0 V. All versions include an internal power switch and synchronous rectifier for minimal external part count and high efficiency. The ADP2108 has an internal soft start and is internally compensated. During logic controlled shutdown, the input is disconnected from the output and the ADP2108 draws less than 1 ?A from the input source.Other key features include undervoltage lockout to prevent deep battery discharge and soft start to prevent input current over-shoot at startup. The ADP2108 is available in 5-ball WLCSP and 5-lead TSOT packages. The ADP2109 provides the same features and operations as the ADP2108 and has the additional function of a discharge switch in the WLCSP package.APPLICATIONS PDAs and palmtop computers Wireless handsets Digital audio, portable media players Digital cameras, GPS navigation units

The ADP2118 is a low quiescent current, synchronous, step-down dc-to-dc regulator in a compact 4mm ? 4mm LFCSP package. It uses a current mode, constant frequency pulse-width modulation (PWM) control scheme for excellent stability and transient response. Under light loads, the ADP2118 can be configured to operate in pulse frequency modulation (PFM) mode that reduces switching frequency to save power. The ADP2118 runs from input voltages of 2.3 V to 5.5 V. The output voltage of the ADP2118ACPZ-R7 is adjustable from 0.6 V to input voltage (VIN), and the ADP2118ACPZ-x.x-R7 are available in preset output voltage options of 1.2 V and 3.3 V. The ADP2118 requires minimal external parts and provides a high efficiency solution with its integrated power switch, synchronous rectifier, and internal compensation. The IC draws less than 3 ?A from the input source when it is disabled. Other key features include undervoltage lockout (UVLO), integrated soft start to limit inrush current at startup, overvoltage protection (OVP), overcurrent protection (OCP), and thermal shutdown (TSD).APPLICATIONS Point of load conversion Communications and networking equipments Industrial and instrumentation Consumer electronics Medical appliances

The AD736 is a low power, precision, monolithic true rms-to-dc converter. It is laser trimmed to provide a maximum error of ?0.3 mV ? 0.3% of reading with sine wave inputs. Furthermore, it maintains high accuracy while measuring a wide range of input waveforms, including variable duty-cycle pulses and triac (phase)-controlled sine waves. The low cost and small size of this converter make it suitable for upgrading the performance of non-rms precision rectifiers in many applications. Compared to these circuits, the AD736 offers higher accuracy at an equal or lower cost.The AD736 can compute the rms value of both ac and dc input voltages. It can also be operated as an ac-coupled device by adding one external capacitor. In this mode, the AD736 can resolve input signal levels of 100 ?V rms or less, despite variations in temperature or supply voltage. High accuracy is also maintained for input waveforms with crest factors of 1 to 3. In addition, crest factors as high as 5 can be measured (introducing only 2.5% additional error) at the 200 mV full-scale input level.The AD736 has its own output buffer amplifier, thereby pro-viding a great deal of design flexibility. Requiring only 200 ?A of power supply current, the AD736 is optimized for use in portable multimeters and other battery-powered applications.The AD736 allows the choice of two signal input terminals: a high impedance FET input (1012 ?) that directly interfaces with High-Z input attenuators and a low impedance input (8 k?) that allows the measurement of 300 mV input levels while operating from the minimum power supply voltage of +2.8 V, ?3.2 V. The two inputs can be used either single ended or differentially.The AD736 has a 1% reading error bandwidth that exceeds 10 kHz for the input amplitudes from 20 mV rms to 200 mV rms while consuming only 1 mW.The AD736 is available in four performance grades. The AD736J and AD736K grades are rated over the 0?C to +70?C and ?20?C to +85?C commercial temperature ranges. The AD736A and AD736B grades are rated over the ?40?C to +85?C industrial temperature range. The AD736 is available in three low cost, 8-lead packages: PDIP, SOIC, and CERDIP.PRODUCT HIGHLIGHTS The AD736 is capable of computing the average rectified value, absolute value, or true rms value of various input signals. Only one external component, an averaging capacitor, is required for the AD736 to perform true rms measurement. The low power consumption of 1 mW makes the AD736 suitable for many battery-powered applications. A high input impedance of 1012 ? eliminates the need for an external buffer when interfacing with input attenuators. A low impedance input is available for those applications that require an input signal up to 300 mV rms operating from low power supply voltages.

The AD737 is a low power, precision, monolithic, true rms-to-dc converter. It is laser trimmed to provide a maximum error of ?0.2 mV ? 0.3% of reading with sine wave inputs. Furthermore, it maintains high accuracy while measuring a wide range of input waveforms, including variable duty cycle pulses and triac (phase) controlled sine waves. The low cost and small physical size of this converter make it suitable for upgrading the performance of non-rms precision rectifiers in many applications. Compared to these circuits, the AD737 offers higher accuracy at equal or lower cost.The AD737 computes the rms value of both the ac and dc input voltages, and is ac-coupled by adding an input capacitor. In this mode, the AD737 can resolve input signal levels of 100 ?V rms or less, despite variations in temperature or supply voltage. High accuracy is maintained for input waveforms with crest factors of 1 to 3 and crest factors at 2.5% or less with respect to full-scale input level.The AD737 has no output buffer amplifier, thereby significantly reducing dc offset errors occurring at the output, which makes the device highly compatible with high input impedance ADCs.Requiring only 160 ?A of power supply current, the AD737 is optimized for use in portable multimeters and other battery-powered applications. In power-down mode, the standby supply current in is typically 25 ?A.The AD737 has both high (1012 ?) and low impedance input options. The high-Z FET input connects high source impedance input attenuators, and a low impedance (8 k?) input accepts rms voltages of up to 0.9 V while operating from the minimum power supply voltage of ?2.5 V. The two inputs can be used either single ended or differentially.The AD737 achieves 1% of reading error bandwidth, exceeding 10 kHz for input amplitudes from 20 mV rms to 200 mV rms, while consuming only 0.72 mW.The AD737 is available in two performance grades. The AD737J and AD737K grades operate over the commercial temperature range of 0?C to 70?C. The AD737JR-5 is tested with supply voltages of ?2.5 V dc. The AD737A grade operates over the industrial temperature range of ?40?C to +85?C. The AD737 is available in two low cost, 8-lead packages: PDIP and SOIC_N.PRODUCT HIGHLIGHTS Computes average rectified, absolute, or true rms value of a signal regardless of waveform. Only one external component, an averaging capacitor, is required for the AD737 to perform true rms measurement. The standby power consumption of 125 ?W makes the AD737 suitable for battery-powered applications.