Analog Devices Inc./Maxim Integrated

MAX1846/MAX1847 high-efficiency PWM inverting controllers allow designers to implement compact, low-noise, negative-output DC-DC converters for telecom and networking applications. Both devices operate from +3V to +16.5V input and generate -500mV to -200V output. To minimize switching noise, both devices feature a current-mode, constant-frequency PWM control scheme. The operating frequency can be set from 100kHz to 500kHz through a resistor.The MAX1846 is available in an ultra-compact 10-pin µMAX® package. Operation at high frequency, compatibility with ceramic capacitors, and inverting topology without transformers allow for a compact design. Compatibility with electrolytic capacitors and flexibility to operate down to 100kHz allow users to minimize the cost of external components. The high-current output drivers are designed to drive a P-channel MOSFET and allow the converter to deliver up to 30W.The MAX1847 features clock synchronization and shutdown functions. The MAX1847 can also be configured to operate as an inverting flyback controller with an N-channel MOSFET and a transformer to deliver up to 70W. The MAX1847 is available in a 16-pin QSOP package.Current-mode control simplifies compensation and provides good transient response. Accurate current-mode control and over current protection are achieved through low-side current sensing.ApplicationsCellular Base StationsCO DSL Line Driver SuppliesIndustrial Power SuppliesNetwork EquipmentOptical Networking EquipmentServersSLIC SuppliesVOIP Supplies

MAX1846/MAX1847 high-efficiency PWM inverting controllers allow designers to implement compact, low-noise, negative-output DC-DC converters for telecom and networking applications. Both devices operate from +3V to +16.5V input and generate -500mV to -200V output. To minimize switching noise, both devices feature a current-mode, constant-frequency PWM control scheme. The operating frequency can be set from 100kHz to 500kHz through a resistor.The MAX1846 is available in an ultra-compact 10-pin µMAX® package. Operation at high frequency, compatibility with ceramic capacitors, and inverting topology without transformers allow for a compact design. Compatibility with electrolytic capacitors and flexibility to operate down to 100kHz allow users to minimize the cost of external components. The high-current output drivers are designed to drive a P-channel MOSFET and allow the converter to deliver up to 30W.The MAX1847 features clock synchronization and shutdown functions. The MAX1847 can also be configured to operate as an inverting flyback controller with an N-channel MOSFET and a transformer to deliver up to 70W. The MAX1847 is available in a 16-pin QSOP package.Current-mode control simplifies compensation and provides good transient response. Accurate current-mode control and over current protection are achieved through low-side current sensing.ApplicationsCellular Base StationsCO DSL Line Driver SuppliesIndustrial Power SuppliesNetwork EquipmentOptical Networking EquipmentServersSLIC SuppliesVOIP Supplies

The MAX1852/MAX1853 monolithic, CMOS charge-pump voltage inverters in the ultra-small SC70 package feature a low 15Ω output resistance, permitting loads up to 30mA with maximum efficiency. The MAX1852/MAX1853 are available with operating frequencies of 50kHz and 200kHz, respectively, allowing optimization of supply current or external component size. Small external components and micropower shutdown mode make these devices ideal for both battery-powered and board-level voltage conversion applications.Oscillator control circuitry and four power-MOSFET switches are included on-chip. Applications include generating a negative supply from a +5V or +3.3V logic supply to power analog circuitry. Both versions come in a 6-pin SC70 package that is 40% smaller than a SOT23.ApplicationsBattery-Powered ApplicationsGaAsFET Bias SuppliesHandy-Terminals, PDAsNegative Supply from +5V or +3.3V Logic SuppliesSmall LCD Panels