Analog Devices Inc./Maxim Integrated

The LTC3409 is a high efficiency, monolithic synchronous buck regulator using a constant frequency, current mode architecture. The output voltage is adjusted via an external resistor divider.Fixed switching frequencies of 1.7MHz and 2.6MHz are supported. Alternatively, an internal PLL will synchronize to an external clock in the frequency range of 1MHz to 3MHz. This range of switching frequencies allows the use of small surface mount inductors and capacitors, including ceramics.Supply current during Burst Mode operation is only 65µA dropping to <1µA in shutdown. The 1.6V to 5.5V input voltage range makes the LTC3409 ideally suited for single cell Li-Ion, Li-Metal and 2-cell alkaline, NiCd or NiMH battery-powered applications. 100% duty cycle capability provides low dropout operation, extending battery life in portable systems. Burst Mode operation can be user enabled, increasing efficiency at light loads, further extending battery life.The internal synchronous switch increases efficiency and eliminates the need for an external Schottky diode. Internal soft-start offers controlled output voltage rise time at start-up without the need for external components.Protected by U.S. Patents, including 5481178, 6580258, 6304066, 6127815, 6498466, 6611131.Vout RangeLTC3409±5%LTC3409A±3%ApplicationsCellular PhonesDigital CamerasMP3 Players

The LTC3409A is a high efficiency, monolithic synchronous buck regulator using a constant frequency, current mode architecture. The LTC3409A improves upon the LTC3409’s light load regulation in Burst Mode operation. The output voltage is adjusted via an external resistor divider.Fixed switching frequencies of 1.7MHz and 2.6MHz are supported. Alternatively, an internal PLL will synchronize to an external clock in the frequency range of 1MHz to 3MHz. This range of switching frequencies allows the use of small surface mount inductors and capacitors, including ceramics.Supply current during Burst Mode operation is only 65μA dropping to <1μA in shutdown. The 1.6V to 5.5V input voltage range makes the LTC3409A ideally suited for single cell Li-Ion, Li-Metal and 2-cell alkaline, NiCd or NiMH battery-powered applications. 100% duty cycle capability provides low dropout operation, extending battery life in portable systems. Burst Mode operation can be user-enabled, increasing efficiency at light loads, further extending battery life.The internal synchronous switch increases efficiency and eliminates the need for an external Schottky diode. Internal soft-start offers controlled output voltage rise time at startup without the need for external components.VREFToleranceLTC3409VREFToleranceLTC3409A±3%ApplicationsCellular PhonesDigital CamerasMP3 Players

The LTC3410B is a high efficiency monolithic synchronous buck regulator using a constant frequency, current mode architecture. The device is available in adjustable and fixed output voltage versions. Supply current during operation is only 200µA, dropping to <1µA in shutdown. The 2.5V to 5.5V input voltage range makes the LTC3410B ideally suited for single Li-Ion battery-powered applications.100% duty cycle provides low dropout operation, extending battery life in portable systems. PWM pulse skipping mode operation provides very low output ripple voltage for noise sensitive applications.Switching frequency is internally set at 2.25MHz, allowing the use of small surface mount inductors and capacitors. The LTC3410B is specifically designed to work well with ceramic output capacitors, achieving very low output voltage ripple and a small PCB footprint.The internal synchronous switch increases efficiency and eliminates the need for an external Schottky diode. Low output voltages are easily supported with the 0.8V feedback reference voltage. The LTC3410B is available in a tiny, low profile SC70 package.VoutBurst ModeLTC3410Adj. Down To 0.8VYesLTC3410BAdj. Down To 0.8VNoLTC3410-1.875Fixed 1.875VYesApplicationsCellular TelephonesPersonal Information AppliancesWireless and DSL ModemsDigital Still CamerasMP3 PlayersPortable Instruments

The LTC3410-1.875 is a high efficiency monolithic synchronous buck regulator using a constant frequency, current mode architecture. Supply current during operation is only 26µA, dropping to <1µA in shutdown. The 2.5V to 5.5V input voltage range makes the LTC3410-1.875 ideally suited for single Li-Ion battery-powered applications. 100% duty cycle provides low dropout operation, extending battery life in portable systems.Switching frequency is internally set at 2.25MHz, allowing the use of small surface mount inductors and capacitors. The LTC3410-1.875 is specifically designed to work well with ceramic output capacitors, achieving very low output voltage ripple and a small PCB footprint.The internal synchronous switch increases efficiency and eliminates the need for an external Schottky diode. The LTC3410-1.875 is available in a tiny, low profile SC70 package.VoutBurst ModeLTC3410Adj. Down To 0.8VYesLTC3410BAdj. Down To 0.8VNoLTC3410-1.875Fixed 1.875VYesApplicationsCellular TelephonesWireless and DSL ModemsDigital CamerasMP3 PlayersPortable Instruments

The LTC3410B is a high efficiency monolithic synchronous buck regulator using a constant frequency, current mode architecture. The device is available in adjustable and fixed output voltage versions. Supply current during operation is only 200µA, dropping to <1µA in shutdown. The 2.5V to 5.5V input voltage range makes the LTC3410B ideally suited for single Li-Ion battery-powered applications.100% duty cycle provides low dropout operation, extending battery life in portable systems. PWM pulse skipping mode operation provides very low output ripple voltage for noise sensitive applications.Switching frequency is internally set at 2.25MHz, allowing the use of small surface mount inductors and capacitors. The LTC3410B is specifically designed to work well with ceramic output capacitors, achieving very low output voltage ripple and a small PCB footprint.The internal synchronous switch increases efficiency and eliminates the need for an external Schottky diode. Low output voltages are easily supported with the 0.8V feedback reference voltage. The LTC3410B is available in a tiny, low profile SC70 package.VoutBurst ModeLTC3410Adj. Down To 0.8VYesLTC3410BAdj. Down To 0.8VNoLTC3410-1.875Fixed 1.875VYesApplicationsCellular TelephonesPersonal Information AppliancesWireless and DSL ModemsDigital Still CamerasMP3 PlayersPortable Instruments

The LTC3411A is a constant frequency, synchronous step-down DC/DC converter. Intended for medium power applications, it operates from a 2.5V to 5.5V input voltage range and has a user configurable operating frequency up to 4MHz, allowing the use of tiny, low cost capacitors and inductors 1mm or less in height. The output voltage is adjustable from 0.8V to 5.5V. Internal synchronous power switches provide high efficiency. The LTC3411A’s current mode architecture and external compensation allow the transient response to be optimized over a wide range of loads and output capacitors.The LTC3411A can be configured for automatic power saving Burst Mode operation (IQ= 40µA) to reduce gate charge losses when the load current drops below the level required for continuous operation. For reduced noise and RF interference, the SYNC/MODE pin can be configured to skip pulses or provide forced continuous operation.To further maximize battery life, the P-channel MOSFET is turned on continuously in dropout (100% duty cycle). In shutdown, the device draws <1µA.ApplicationsNotebook ComputersDigital CamerasCellular PhonesHandheld InstrumentsBoard Mounted Power Supplies

The LTC3411A is a constant frequency, synchronous step-down DC/DC converter. Intended for medium power applications, it operates from a 2.5V to 5.5V input voltage range and has a user configurable operating frequency up to 4MHz, allowing the use of tiny, low cost capacitors and inductors 1mm or less in height. The output voltage is adjustable from 0.8V to 5.5V. Internal synchronous power switches provide high efficiency. The LTC3411A’s current mode architecture and external compensation allow the transient response to be optimized over a wide range of loads and output capacitors.The LTC3411A can be configured for automatic power saving Burst Mode operation (IQ= 40µA) to reduce gate charge losses when the load current drops below the level required for continuous operation. For reduced noise and RF interference, the SYNC/MODE pin can be configured to skip pulses or provide forced continuous operation.To further maximize battery life, the P-channel MOSFET is turned on continuously in dropout (100% duty cycle). In shutdown, the device draws <1µA.ApplicationsNotebook ComputersDigital CamerasCellular PhonesHandheld InstrumentsBoard Mounted Power Supplies