DATASHEET ISL8023, ISL8024 FN7812 Rev 3.00 Compact Synchronous Buck Regulator March 24, 2014 The ISL8023, ISL8024 are highly efficient, monolithic, Features synchronous step-down DC/DC converters that can deliver 3A 2.7V to 5.5V input voltage range (ISL8023) or 4A (ISL8024) of continuous output current from a 2.7V to 5.5V input supply. The devices use current mode control Very low on-resistance FETs - P-Channel 45m and architecture to deliver very low duty cycle operation at high N-Channel 19m typical values frequency with fast transient response and excellent loop stability. High efficiency synchronous buck regulator with up to 95% The ISL8023 and ISL8024 integrate a very low On-resistance efficiency P-Channel (45m ) high side FET and N-Channel (19m) low 0.8% reference accuracy over-temperature/load/line side FET to maximize efficiency and minimize external Complete BOM with as few as 3 external parts component count. The 100% duty-cycle operation allows less than 200mV dropout voltage at 4A output current. The Start-up with pre-biased output operation frequency of the pulse-width modulator (PWM) is Internal soft-start - 1ms or adjustable adjustable from 500kHz to 4MHz. The default switching Soft-stop output discharge during disabled frequency of 1MHz is set by connecting the FS pin high, which allows for the use of small external components. Adjustable frequency from 500kHz to 4MHz - default at 1MHz (8023/24), 2MHz (8023A/24A) The ISL8023, ISL8024 can be configured for discontinuous or forced continuous operation at light load. Forced continuous External synchronization up to 4MHz operation reduces noise and RF interference while Over-temperature, Overcurrent, Overvoltage and negative discontinuous mode provides higher efficiency by reducing overcurrent protection switching losses at light loads. Tiny 3x3 QFN package Fault protection is provided by internal hiccup mode current limiting during short circuit and overcurrent conditions. Other Applications protection, such as overvoltage and over-temperature are also DC/DC POL modules integrated into the device. A power-good output voltage C/P, FPGA and DSP power monitor indicates when the output is in regulation. Plug-in DC/DC modules for routers and switchers The ISL8023, ISL8024 offer a 1ms Power-Good (PG) timer at power-up. When in shutdown, ISL8023, ISL8024 discharges Portable instruments the output capacitor through an internal soft-stop switch. Other Test and measurement systems features include internal fixed or adjustable soft-start and Li-ion battery powered devices internal/external compensation. The ISL8023 and ISL8024 are offered in a space saving 16 Ld Related Literature 3x3 Pb-free QFN package with an exposed pad for improved See AN1759, 3A/4A Low Quiescent Current High Efficiency thermal performance and 1mm maximum height. The Synchronous Buck Regulator 2 complete converter occupies less than 0.22 in area. Various fixed output voltages are available upon request. See the Ordering Information on page 4 for more details. 100 90 3.3V PFM OUT 80 3.3V PWM 70 OUT 60 50 40 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 I (A) OUT FIGURE 1. EFFICIENCY T = +25C, V = 5V IN FN7812 Rev 3.00 Page 1 of 20 March 24, 2014 EFFICIENCY (%)ISL8023, ISL8024 NOTE: Full solution in size board. The full schematic and Gerber files are available for down load from Intersil.com. FN7812 Rev 3.00 Page 2 of 20 March 24, 2014