ISL8105B

Features:

• Operates from +5V or +12V Bias Supply Voltage
- 1.0V to 12V Input Voltage Range (up to 20V possible
with restrictions; see Input Voltage Considerations)
- 0.6V to V_IN Output Voltage Range
• 0.6V Internal Reference Voltage
- ±1.0% Tolerance Over the Commercial Temperature Range (0to +70)
- ±1.5% Tolerance Over the Industrial Temperature Range (-40 to +85).
• Integrated MOSFET Gate Drivers that Operate from V_BIAS (+5V to +12V)
- Bootstrapped High-side Gate Driver with Integrated Boot Diode
- Drives N-Channel MOSFETs
• Simple Voltage-Mode PWM Control
• Fast Transient Response
- High-Bandwidth Error Amplifier
- Full 0% to 100% Duty Cycle
• Fixed 300kHz Operating Frequency
• Fixed Internal Soft-Start with Pre-biased Load Capability
• Lossless, Programmable Overcurrent Protection
- Uses Bottom-side MOSFET's r_DS(ON)
• Enable/Disable Function Using COMP/EN Pin
• Output Current Sourcing and Sinking Currents
• Pb-Free Plus Anneal Available (RoHS Compliant)




Application

• 5V or 12V DC/DC Regulators
• Industrial Power Systems
• Telecom and Datacom Applications
• Test and Measurement Instruments
• Distributed DC/DC Power Architecture
• Point of Load Modules




Pinout






Specifications

Bias Voltage, V_BIAS . . . . . . . . . . . . . .. . . GND - 0.3V to +15.0V
Boot Voltage, V_BOOT. . . . . . . . . . . . . . . . GND - 0.3V to +36.0V
TGATE Voltage, V_TGATE . . . . . . . . . . V_LX - 0.3V to V_BOOT + 0.3V
BGATE/BSOC Voltage, V_BGATE/BSOC . .GND - 0.3 to V_BIAS + 0.3V
LX Voltage, V_LX . . . . . . . . . . . . . . . GND - 0.3V to _VBOOT + 0.3V
Upper Driver Supply Voltage, V_BOOT - V_LX . . . . . . . . . . . . . .15V
Clamp Voltage, V_BOOT - V_BIAS . . . . . . . . . . . . . . . . . . . . .. .24V
FB, COMP/EN Voltage . . . . . . . . . . . . . . . . . . . GND - 0.3V to 6V
ESD Classification, HBM . . . . . . . . . . . . . . . . . . . . . . . . . . 1.5kV
ESD Classification, MM . . . . . . . . . . . . . . . . . . . . . . .. . .. . .150V
ESD Classification, CDM . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0kV

CAUTION: Stresses above those listed in "Absolute Maximum Ratings" may cause permanent damage to the device. This is a stress only rating and operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
NOTE:
1. _JA is measured in free air with the component mounted on a high effective thermal conductivity test board with "direct attach" features.
2. For _JC, the "case temp" location is the center of the exposed metal pad on the package underside.
3. Test conditions are guaranteed by design simulation.

Description

The ISL8105B is a simple single-phase PWM controller for a synchronous buck converter. It operates from +5V or +12V bias supply voltage. With integrated linear regulator, boot diode, and N-Channel MOSFET gate drivers, the ISL8105B reduces external component count and board space requirements. These make the IC suitable for a wide range of applications. Utilizing voltage-mode control, the output voltage can be precisely regulated to as low as 0.6V. The 0.6V internal reference features a maximum tolerance of 1.0% over the commercial temperature range, and 1.5% over the industrial temperature range. The controller operates with a fixed switching frequency of 300kHz. The ISL8105B features the capability of safe start-up with pre-biased load. It also provides overcurrent protection by monitoring the ON-resistance of the bottom-side MOSFET to inhibit PWM operation appropriately. During start-up interval, the resistor connected to BGATE/BSOC pin is employed to program overcurrent protection condition. This approach simplifies the implementation and does not deteriorate converter efficiency.