ISL95808HRZ-T

DATASHEET ISL95808 FN8689 Rev 2.00 May 25, 2016 High Voltage Synchronous Rectified Buck MOSFET Driver The ISL95808 is a high frequency, dual MOSFET driver with low shutdown current, optimized to drive two N-Channel power MOSFETs in a synchronous-rectified buck converter topology. It is especially suited for mobile computing applications that require high efficiency and excellent thermal performance. The driver, combined with an Intersil multiphase Buck PWM controller, forms a complete single-stage core-voltage regulator solution for advanced mobile microprocessors. The ISL95808 features a 4A typical sinking current for the lower gate driver. This current is capable of holding the lower MOSFET gate off during the rising edge of the phase node. This prevents shoot-through power loss caused by the high dv/dt of phase voltages. The operating voltage matches the 30V breakdown voltage of the MOSFETs commonly used in mobile computer power supplies. Features • Dual MOSFET drivers for synchronous rectified bridge • Adaptive shoot-through protection • 0.5Ω ON-resistance and 4A sink current capability • Supports high switching frequency up to 2MHz - Fast output rise and fall time - Low propagation delay • Three-state PWM input for power stage shutdown • Internal bootstrap Schottky diode • Low shutdown supply current (5V, 3µA) • Diode emulation for enhanced light-load efficiency and prebiased start-up applications • VCC POR (Power-On Reset) feature integrated The ISL95808 also features a three-state PWM input. This PWM input, working together with Intersil’s multiphase PWM controllers, will prevent negative voltage output during CPU shutdown. This feature eliminates a protective Schottky diode usually seen in microprocessor power systems. • Low three-state shutdown hold-off time (typical 160ns) • DFN package • Pb-free (RoHS compliant) MOSFET gates can be efficiently switched up to 2MHz using the ISL95808. Each driver is capable of driving a 3000pF load with propagation delays of 8ns and transition times under 10ns. Bootstrapping is implemented with an internal Schottky diode. This reduces system cost and complexity, while allowing for the use of higher performance MOSFETs. Adaptive shoot--through protection is integrated to prevent both MOSFETs from conducting simultaneously. A diode emulation feature is integrated in the ISL95808 to enhance converter efficiency at light load conditions. This feature also allows for monotonic start-up into prebiased outputs. When diode emulation is enabled, the driver will allow discontinuous conduction mode by detecting when the inductor current reaches zero and subsequently turning off the low-side MOSFET gate. Applications • Core voltage supplies for Intel® and AMD™ mobile microprocessors • High frequency low profile DC/DC converters • High current low output voltage DC/DC converters • High input voltage DC/DC converters Related Literature • TB389, “PCB Land Pattern Design and Surface Mount Guidelines for MLFP Packages” • TB447, “Guidelines for Preventing Boot-to-Phase Stress on Half-Bridge MOSFET Driver ICs” The ISL95808 also features very low shutdown supply current (5V, 3µA) to ensure the low power consumption. VCC BOOT FCCM UGATE SHOOTTHROUGH PROTECTION PWM 10kΩ CONTROL LOGIC PHASE VCC LGATE GND THERMAL PAD FIGURE 1. BLOCK DIAGRAM FN8689 Rev 2.00 May 25, 2016 Page 1 of 9 ISL95808 Ordering Information PART NUMBER (Notes 1, 2, 3) PART MARKING TEMP. RANGE (°C) TAPE AND REEL (UNITS) PACKAGE (RoHS Compliant) PKG. DWG. # ISL95808HRZ-T 08 -10 to +100 6k 8 Ld 2x2 DFN L8.2x2D ISL95808IRZ-T 08I -40 to +100 6k 8 Ld 2x2 DFN L8.2x2D NOTES: 1. Please refer to TB347 for details on reel specifications. 2. These Intersil Pb-free plastic packaged products employ special Pb-free material sets, molding compounds/die attach materials, and 100% matte tin plate plus anneal (e3 termination finish, which is RoHS compliant and compatible with both SnPb and Pb-free soldering operations). Intersil Pbfree products are MSL classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020. 3. For Moisture Sensitivity Level (MSL), please see product information page for ISL95808. For more information on MSL, please see tech brief TB363. Pin Configuration ISL95808 (8 LD 2x2 DFN) TOP VIEW UGATE 1 86 PHASE BOOT 2 7 FCCM PWM 3 66 VCC GND 4 5 LGATE Pin Descriptions PIN NUMBER PIN NAME 1 UGATE The UGATE pin is the upper gate drive output. Connect to the gate of high-side power N-Channel MOSFET. 2 BOOT BOOT is the floating bootstrap supply pin for the upper gate drive. Connect the bootstrap capacitor between this pin and the PHASE pin. The bootstrap capacitor provides the charge to turn on the upper MOSFET. See “Internal Bootstrap Diode” on page 7 for guidance in choosing the appropriate capacitor value. 3 PWM The PWM signal is the control input for the driver. The PWM signal can enter three distinct states during operation. See “Three-State PWM Input” on page 6 for further details. Connect this pin to the PWM output of the controller. 4 GND GND is the ground pin for the IC. 5 LGATE 6 VCC Connect the VCC pin to a +5V bias supply. Place a high quality bypass capacitor from this pin to GND. The VCC pin of the driver(s) and related VCC or +5V bias supply pin of the Intersil controller must share a common +5V supply. 7 FCCM The FCCM pin enables or disables diode emulation. When FCCM is LOW, diode emulation is allowed. When FCCM is HIGH, continuous conduction mode is forced. See “Diode Emulation” on page 6 for more detail. High impedance on the input of FCCM will shut down ISL95808. 8 PHASE Connect the PHASE pin to the source of the upper MOSFET and the drain of the lower MOSFET. This pin provides a return path for the upper gate driver. FN8689 Rev 2.00 May 25, 2016 DESCRIPTION LGATE is the lower gate drive output. Connect to gate of the low-side power N-Channel MOSFET. Page 2 of 9 ISL95808 i Absolute Maximum Ratings Thermal Information Supply Voltage (VCC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 7V Input Voltage (VFCCM, VPWM) . . . . . . . . . . . . . . . . . . . . -0.3V to VCC + 0.3V BOOT Voltage (VBOOT-GND) . . . . . . . . . . . . . . . -0.3V to 33V or 36V (