ISL6269CRZ

The ISL6269CRZ belongs to the ISL6269, the IC is a single-phase synchronous-buck PWM controller featuring intersil's robust ripple regulator (R3) technology that delivers truly superior dynamic response to input voltage and output load transients. Integrated MOSFET drivers, 5V LDO, and bootstrap diode result infewer components and smaller implementation area. Intersil's R3 technology combines the best features of fixed-frequency PWM and hysteretic PWM while eliminating manyof their shortcomings. R3 technology employs an innovativemodulator that synthesizes an AC ripple voltage signal VR,analogous to the output inductor ripple current. The ACsignal VR enters a hysteretic comparator where the lowerthreshold is the error amplifier output VCOMP, and the upperthreshold is a programmable voltage reference VW, resultingin generation of the PWM signal. The voltage reference VWsets the steady-state PWM frequency. Both rising and fallingedges of the PWM are modulated, providing faster responseto input voltage transients and output load transients thanconventional fixed-frequency PWM controllers. Unlike aconventional hysteretic converter, the ISL6269CRZ has an erroramplifier that provides ±1% voltage regulation at the FB pin.The ISL6269CRZ  has a 1.5ms digital soft-start and can bestarted into a pre-biased output voltage. A resistor divider isused to program the output voltage setpoint. The ISL6269CRZ can be configured to operate in forced-continuous-conduction-mode (FCCM) or in diode-emulation-mode(DEM), which improves light-load efficiency. In FCCM thecontroller always operates as a synchronous rectifier,switching the low-side MOSFET regardless of the outputload, however with DEM enabled, the low-side MOSFET isdisabled preventing negative current flow from the outputinductor during low load operation. An audio filter preventsthe PWM switching frequency from entering the audiblespectrum due to extremely light load while in DEM. A PGOOD pin indicates when the converter is capable ofsupplying regulated voltage. The ISL6269CRZ  features a uniquefault-identification capability that can drastically reducetrouble-shooting time and effort. The pull-down resistance ofthe PGOOD pin is 30 for an overcurrent fault, 60 for anovervoltage fault, or 90 for either an undervoltage fault orduring soft-start. The overcurrent protection is accomplishedby measuring the voltage drop across the rDS(ON) of thelow-side MOSFET. A single resistor programs theovercurrent and short-circuit points. Overvoltage andundervoltage protection is monitored at the FB voltagefeedback pin.

The features of ISL6269CRZ are (1)high performance synthetic ripple regulation; (2)extremely fast transient response; (3)external type-two loop compensation; (4)±1% regulation accuracy: -10°C to +100°C; (5)Pb-Free plus anneal available (RoHS compliant); (6)starts into a pre-biased output; (7)wide input voltage range: +7.0V to +25.0V; (8)wide output voltage range: +0.6V to +3.3V; (9)wide output load range: 0A to 25A; (10)programmable PWM frequency: 200kHz to 600kHz; (11)power good monitor; (12)fault identification by PGOOD pull down resistance; (13)integrated MOSFET drivers with shoot-through protection; (14)internal digital soft-start; (15)internal 5V LDO regulator; (16)configure forced continuous conduction or diode: emulation for increased light load efficiency; (17)PWM minimum frequency above audible spectrum; (18)integrated boot-strap diode; (19)low-side MOSFET rDS(ON) overcurrent protection; (20)undervoltage protection; (21)soft crowbar overvoltage protection; (22)over-temperature protection.

The absolute maximum ratings of ISL6269CRZ are (1)ISEN, VIN to GND: -0.3V to +28V; (2)VCC, PGOOD to GND: -0.3V to +7.0V; (3)PVCC to PGND:-0.3V to +7.0V; (4)GND to PGND: -0.3V to +0.3V; (5)EN, FCCM: -0.3V to GND, VCC +3.3V; (6)PHASE to GND: (DC) -0.3V to +28V (<100ns Pulse Width, 10µJ) -5.0V; (7)BOOT to GND, or PGND: -0.3V to +33V; (8)BOOT to PHASE: -0.3V to +7V; (9)UG: (DC) -0.3V to PHASE, BOOT +0.3V(<200ns pulse width, 20µJ) -4.0V; (10)LG: (DC) -0.3V to PGND, PVCC +0.3V (<100ns pulse width, 4µJ) -2.0V; (11)ESD classification: level 1 (HBM = 2kV); (12)thermal information(junction temperature range: -55°C to +150°C; operating temperature range :-10°C to +100°C; storage temperature: -65°C to +150°C; lead temperature: (soldering, 10s)+300°C); (13)ambient temperature range: -10°C to 100°C; (14)supply voltage (VIN to GND): 7V to 25V.