The ISL8023, ISL8024IRTAJZ-T7 are highly efficient, monolithic, synchronous step-down DC/DC converters that can deliver 3A (ISL8023) or 4A (ISL8024) of continuous output current from a 2.7V to 5.5V input supply. The devices use current mode control architecture to deliver very low duty cycle operation at high frequency with fast transient response and excellent loop stability.The ISL8023 and ISL8024IRTAJZ-T7 integrate a very low On-resistance P-Channel (45mΩ) high side FET and N-Channel (19mΩ) low side FET to maximize efficiency and minimize external component count. The 100% duty-cycle operation allows less than 200mV dropout voltage at 4A output current. The operation frequency of the pulse-width modulator (PWM) is adjustable from 500kHz to 4MHz. The default switching frequency of 1MHz is set by connecting the FS pin high, which allows for the use of small external components.The ISL8023, ISL8024IRTAJZ-T7 can be configured for discontinuous or forced continuous operation at light load. Forced continuous operation reduces noise and RF interference while discontinuous mode provides higher efficiency by reducing switching losses at light loads.Fault protection is provided by internal hiccup mode current limiting during short circuit and overcurrent conditions. Other protection, such as overvoltage and over-temperature are also integrated into the device. A power-good output voltage monitor indicates when the output is in regulation. The ISL8023, ISL8024IRTAJZ-T7 offer a 1ms Power-Good (PG) timer at power-up. When in shutdown, ISL8023, ISL8024IRTAJZ-T7 discharges the output capacitor through an internal soft-stop switch. Other features include internal fixed or adjustable soft-start and internal/external compensation.The ISL8023 and ISL8024IRTAJZ-T7 are offered in a space saving 16 Ld 3x3 Pb-free QFN package with an exposed pad for improved thermal performance and 1mm maximum height. The complete converter occupies less than 0.22 in2 area. Various fixed output voltages are available upon request. See the “Ordering Information” on page 4 for more details.
Feature
- 2.7V to 5.5V input voltage range
- Very low on-resistance FET’s - P-Channel 45mΩ and N-Channel 19mΩ typical values
- High efficiency synchronous buck regulator with up to 95% efficiency
- 0.8% reference accuracy over-temperature/load/line
- Complete BOM with as few as 3 external parts
- Start-up with pre-biased output
- Internal soft-start - 1ms or adjustable
- Soft-stop output discharge during disabled
- Adjustable frequency from 500kHz to 4MHz - default at 1MHz (8023/24), 2MHz (8023A/24A)
- External synchronization up to 4MHz
- Over-temperature, Overcurrent, Overvoltage and negative overcurrent protection
- Tiny 3x3 QFN package