May 9, 2012 – Linear Technology Korea (CEO Hong Sa-kwak) announced the launch of new high-voltage charge pump products LTC3260 and LTC3261 with diverse functionality. The LTC3261 is a high-voltage inverting charge pump capable of providing maximum output current of 100mA. The LTC3260 features the same charge pump as the LTC3261 but additionally includes both positive and negative LDO regulators, each capable of sourcing maximum output current of 50mA. The negative LDO post-regulator is powered from the inverting charge pump output. The positive and negative LDO output voltages can be adjusted to as low as 1.2V and -1.2V respectively using external resistive dividers. Both devices operate over a wide input voltage range of 4.5V to 32V.
The internal charge pump of LTC3260 and LTC3261 operates at maximum efficiency of 88% in low quiescent current Burst Mode® operation or low-noise fixed frequency mode. During Burst Mode operation, the charge pump output regulates to –0.94 • VIN. Additionally, in Burst Mode operation, the LTC3261 has quiescent current consumption of only 60μA, while the LTC3260 consumes only 100μA of power even with both LDOs running. Fixed frequency operation provides low input and output ripple. In this mode, the charge pump generates output equivalent to –VIN and operates at fixed 500kHz or at values programmed within the 50kHz to 500kHz range using an external resistor. Other features include minimal external component usage based on stability with ceramic capacitors, a soft-start circuit to prevent excessive current flow during startup, and short-circuit and thermal protection functions. The LTC3260 and LTC3261 are used in various applications such as low-noise bias generators for high-voltage industrial and instrumentation, low-noise bipolar/inverting supplies for portable medical equipment and automotive infotainment systems.
The LTC3260 is available in low-profile (0.75mm) 3mm x 4mm 14-pin DFN and 16-pin MSOP packages, with both packages featuring thermal pads on the back side. The LTC3261 is available in a 12-pin MSOP package with thermal pad on the back side. Both devices have temperature range of -40°C to +125°C for E and I grades. E-grade pricing starts at $3.40 for LTC3260 and $2.87 for LTC3261 in quantities of 1,000 units. These products are currently available for immediate purchase, and detailed product information can be found at www.linear.com/product/LTC3260 and www.linear.com/product/LTC3261.

Photo Description: Low-Noise High-Voltage Inverting Charge Pump

LTC3260: Dual Supply Inverting Charge Pump
• VIN Range: 4.5V to 32V
• Inverting Charge Pump Generates –VIN
• Charge Pump Output Current Maximum 100mA
• Low-Noise Negative LDO Post-Regulator (ILDO- = 50mA Maximum)
• Low-Noise Separate Positive LDO Regulator (ILDO+ = 50mA Maximum)
• Quiescent Current Consumption of 100μA in Burst Mode with Both LDO Regulators Running
• LDO Dropout = 300mV at 50mA
• 50kHz to 500kHz Programmable Oscillator Frequency
• Stable Operation with Ceramic Capacitors
• Short-Circuit/Thermal Protection Functions
• Low-Profile 3mm × 4mm 14-pin DFN and Enhanced Thermal Performance 16-pin MSOP Package

LTC3261: Inverting Charge Pump
• VIN Range: 4.5V to 32V
• Inverting Charge Pump Generates –VIN
• Charge Pump Output Current Maximum 100mA
• Quiescent Current Consumption of 60mA in Burst Mode
• 50kHz to 500kHz Programmable Oscillator Frequency
• Short-Circuit/Thermal Protection Functions
• Low-Profile 12-pin MSOP Package with Enhanced Thermal Performance