Features: ` High Voltage Operation: Up to 100V
` Large 1 Gate Drivers
` No Current Sense Resistor Required
` Dual N-Channel MOSFET Synchronous Drive
` Extremely Fast Transient Response
` ±0.5% 0.8V Voltage Reference
` Programmable Output Voltage Tracking/Soft-Start
` Generates 10V Driver Supply from Input Supply
` Synchronizable to External Clock
` Selectable Pulse Skip Mode Operation
` Power Good Output Voltage Monitor
` Adjustable On-Time/Frequency: tON(MIN) < 100ns
` Adjustable Cycle-by-Cycle Current Limit
` Programmable Undervoltage Lockout
` Output Overvoltage Protection
` 28-Pin SSOP PackageApplication· 48V Telecom and Base Station Power Supplies
· Networking Equipment, Servers
· Automotive and Industrial Control SystemsPinout
SpecificationsSupply Voltages
INTVCC, DRVCC ...................................... 0.3V to 14V
(DRVCC - BGRTN), (BOOST - SW) ........... 0.3V to 14V
BOOST ................................................. 0.3V to 114V
BGRTN ........................................................ 5V to 0V
EXTVCC .................................................. 0.3V to 15V
(NDRV - INTVCC) Voltage ....................... 0.3V to 10V
SW, SENSE+ Voltage .............................. 1V to 100V
ION Voltage .......................................... 0.3V to 100V
SS/TRACK Voltage .................................... 0.3V to 5V
PGOOD Voltage ........................................ 0.3V to 7V
VRNG, VON, MODE/SYNC, SHDN,
UVIN Voltages ........................................ 0.3V to 14V
PLL/LPF, FB Voltages ............................. 0.3V to 2.7V
TG, BG, INTVCC, EXTVCC RMS Currents ...............50mA
Operating Temperature Range (Note 2)
LTC3810E .............................................. 40 to 85
LTC3810I.............................................. 40 to 125
Junction Temperature (Notes 3, 7)....................... 125
Storage Temperature Range ................ 65 to 150
Lead Temperature (Soldering, 10 sec) ................ 300
Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime.
Note 2: The LTC3810E is guaranteed to meet performance specifi cations from 0 to 85. Specifi cations over the 40 to 85 operating temperature range are assured by design, characterization and correlation with statistical process controls. The LTC3810I is guaranteed to meet perfomance specifi cations over the full 40 to 125 operating temperature range.
Note 3: TJ is calculated from the ambient temperature TA and power dissipation PD according to the following formula:
LTC3810: TJ = TA + (PD • 100/W)
Note 7: This IC includes overtemperature protection that is intended to protect the device during momentary overload conditions. Junction temperature will exceed 125 when overtemperature protection is active.Continuous operation above the specifi ed maximum operating junction temperature may impair device reliability.
DescriptionThe LTC3810 is a synchronous step-down switching regulator controller that can directly step-down voltages from up to 100V, making it ideal for telecom and automotive applications. The LTC3810 uses a constant on-time valley current control architecture to deliver very low duty cycles with accurate cycle-by-cycle current limit, without requiring a sense resistor.
A precise internal reference provides 0.5% DC accuracy. A high bandwidth (25MHz) error amplifi er provides very fast line and load transient response. Large 1 gate drivers allow the LTC3810 to drive multiple MOSFETs for higher current applications. The operating frequency is selected by an external resistor and is compensated for variations in VIN and can also be synchronized to an external clock for switching-noise sensitive applications. A shutdown pin allows the LTC3810 to be turned off, reducing the supply current to 240A.
Integrated bias control generates gate drive power from the input supply during start-up and when an output shortcircuit occurs, with the addition of a small external SOT23 MOSFET. When in regulation, power is derived from the output for higher effi ciency.
LTC3810 Data Sheet
