Analog Devices Inc./Maxim Integrated

The MAX16425/MAX16425A are fully-integrated, highly efficient step-down DC-DC switching regulators. These devices operate from 4.5V to 16V input supplies, and the output can be adjusted from 0.6V to 3.3V, delivering up to 25A of load current. These single-chip regulators provide a compact high-efficiency, power-delivery solution for precision outputs that demand fast transient responseThe two devices have different programmability options (see Table 3a and 3b for details) to enable a wide range of configurations. The programmable features include: internal/external reference voltage, output voltage set-point, switching frequency, overcurrent protection level (OCP), and soft-start timing. Discontinuous current mode (DCM) operation can be enabled through pin-strapping to improve light-load efficiency.The MAX16425/MAX16425A include multiple protection and measurement features. Positive and negative cycleby- cycle OCP, short-circuit protection and overtemperature protection (OTP) ensure robust design. Input undervoltage and overvoltage lockout shut down the regulator to prevent damage when the input voltage is out of specification. Regulation is halted in case of an output overvoltage (OVP) event. A status pin indicates that the output voltage is within range and the output voltage is in regulation. The device has an analog output that can be configured to report output current or junction temperature with ±5% and ±8°C accuracy, respectively.The devices are available in a 27-bump (2.2mm x 3.8mm) WLCSP package that provides low thermal resistance and minimizes the PCB area.APPLICATIONSServers/μServersI/O and Chipset SuppliesGPU Core SupplyDDR Memory: VDDQ, VPP and VTTPoint-of-Load (PoL) Applications

The MAX1644 constant-off-time, PWM step-down DC-DC converter is ideal for use in applications such as PC cards, CPU daughter cards, and desktop computer bus-termination boards. The device features internal synchronous rectification for high efficiency and reduced component count. It requires no external Schottky diode. The internal 0.10Ω PMOS power switch and 0.10Ω NMOS synchronous-rectifier switch easily deliver continuous load currents up to 2A. The MAX1644 produces a preset +3.3V or +2.5V output voltage or an adjustable output from +1.1V to VIN. It achieves efficiencies as high as 95%.The MAX1644 uses a unique current-mode, constant-off-time, PWM control scheme, which includes an Idle Mode™ to maintain high efficiency during light-load operation. The programmable constant-off-time architecture sets switching frequencies up to 350kHz, allowing the user to optimize performance trade-offs between efficiency, output switching noise, component size, and cost. The device also features an adjustable soft-start to limit surge currents during start-up, a 100% duty cycle mode for low-dropout operation, and a low-power shutdown mode that disconnects the input from the output and reduces supply current below 1µA. The MAX1644 is available in a 16-pin SSOP package.Applications+3.3V PC Card and CardBus Applications+5V to +3.3V/+2.5V ConversionCPU Daughter Card SupplyCPU I/O SuppliesDesktop Bus-Termination BoardsNotebook and Subnotebook Computers

The MAX1645B is a high-efficiency battery charger capable of charging batteries of any chemistry type. It uses the Intel System Management Bus (SMBus™) to control voltage and current-charge outputs.When charging lithium-ion (Li+) batteries, the MAX1645B automatically transitions from regulating current to regulating voltage. The MAX1645B can also limit line input current so as not to exceed a predetermined current drawn from the DC source. A 175s charge safety timer prevents "runaway charging" should the MAX1645B stop receiving charging voltage/current commands.The MAX1645B employs a next-generation synchronous buck control circuitry that lowers the minimum input-to-output voltage drop by allowing the duty cycle to exceed 99%. The MAX1645B can easily charge one to four series Li+ cells.ApplicationsNotebook ComputersPersonal Digital AssistantsPoint-of-Sale Terminals

The MAX1647/MAX1648 provide the power control necessary to charge batteries of any chemistry. In the MAX1647, all charging functions are controlled through the Intel® System Management Bus (SMBus™) interface. The SMBus 2-wire serial interface sets the charge voltage and current, and provides thermal status information. The MAX1647 functions as a level 2 charger, compliant with the Duracell®/Intel Smart Battery Charger Specification. The MAX1648 omits the SMBus serial interface, and instead sets the charge voltage and current proportional to the voltage applied to external control pins.In addition to the feature set required for a level 2 charger, the MAX1647 generates interrupts to signal the host when power is applied to the charger or a battery is installed or removed. Additional status bits allow the host to check whether the charger has enough input voltage, and whether the voltage on or current into the battery is being regulated. This allows the host to determine when lithium-ion batteries have completed charge without interrogating the battery.The MAX1647 is available in a 20-pin SSOP with a 2mm profile height. The MAX1648 is available in a 16-pin SO package.ApplicationsCharger Base StationsNotebook ComputersPDAs and Other Handheld DevicesPhones

The MAX1649/MAX1651 BiCMOS, step-down, DC-DC switching controllers provide high efficiency over loads ranging from 1mA to more than 2.5A. A unique, current-limited pulse-frequency-modulated (PFM) control scheme gives these devices the benefits of pulse-width-modulation (PWM) converters (high efficiency at heavy loads), while using only 100µA of supply current (vs. 2mA to 10mA for PWM converters). Dropout performance down to 300mV is provided by a high switch duty cycle (96.5%) and a low current-sense threshold (110mV).A high switching frequency (up to 300kHz) allows these devices to use miniature external components.The MAX1649/MAX1651 have dropout voltages less than 0.3V at 500mA and accept input voltages up to 16V. Output voltages are preset at 5V (MAX1649), or 3.3V (MAX1651). They can also be adjusted to any voltage from 1.5V to the input voltage by using two resistors.These step-down controllers drive external P-channel MOSFETs at loads greater than 12.5W. If less power is required, use the MAX639/MAX640/MAX653 step-down converters with on-chip FETs, which allow up to a 225mA load current.Applications5V to 3.3V Green PC ApplicationsBattery-Powered ApplicationsHigh-Efficiency Step-Down RegulationPDAs

The MAX16491 is a fully integrated, highly efficient, step-down DC-DC switching regulator. The device operates from 4.5V to 16V input supplies, and the output can be adjusted from 0.6V to 5.5V, delivering up to 9A of load current. This single-chip regulator provides compact high-efficiency power delivery for precision outputs that demand fast transient response.The device has different programmability options to enable a wide range of configurations. The programmable features include: internal/external reference voltage, output voltage set-point, switching frequency, overcurrent-protection level (OCP), and soft-start timing. Discontinuous current mode (DCM) operation can be enabled using pin-strapping to improve light-load efficiency.The MAX16491 includes multiple protection and measurement features. Positive and negative cycle-by-cycle OCP, short-circuit protection and overtemperature protection (OTP) ensure robust design. Input undervoltage and overvoltage lockout shut down the regulator to prevent damages when the input voltage is out of specification. Regulation is halted in case of an output overvoltage (OVP) event. A status pin indicates that the output voltage is within range and the outputvoltage is in regulation. The device has an analog output that can be configured to report output current or junction temperature.The device is available in a 19-bump (2.2mm x 2.8mm) WLCSP package that provides low thermal resistance and minimizes the printed circuit board area.APPLICATIONSServers/μServersI/O and Chipset SuppliesGPU Core SupplyDDR Memory: VDDQ, VPP, and VTTPoint-of-Load (PoL) Applications

5µs, 8-Bit ADC with Track/Hold and Reference