IR Unveils IRF7811 and IRF7809 Low-Voltage HEXFET Power MOSFETs
International Rectifier (IR, El Segundo, CA) introduced its new IRF7811 and IRF7809, a pair of low-voltage HEXFET power MOSFETs. The chip set is claimed to be the industry's first solution to achieve the 90 percent overall efficiency for the CPU core plus peripheral dc/dc converters recommended by Intel's Mobile Power Guidelines 2000 specification. "Using our knowledge of low-voltage dc/dc converter applications and their synchronous rectification topology, we modeled and then optimized our MOSFET technology to maximize system performance demanded to power future mobile CPUs operating as low as 1.3V and in excess of 12A power consumption," stated Gene Sheridan, vice president of IR's processor power group. "We developed two new silicon technologies that deliver devices with the best overall performance within the application-specific power supply topology."The MOSFETs incorporate IR's new "CopperStrap" interconnect technology, which is claimed to reduce junction operating temperatures by as much as 20 percent and eliminate the need for paralleled devices. The 30Vds, +/-12Vgs CopperStrap devices are capable of current ratings over 17A and power dissipation of 3.5W at 25 degrees C ambient. The IRF7811 offers a typical on-resistance of 9 milliohms (11 milliohms max) at Vgs=4.5V with Qg=17nC and Qswitch= 5.8nC. The IRF7809 is claimed to provide the lowest Rds(on) ever achieved at Vgs=4.5V in an SO-8 with typical ratings of 6 milliohms (7.5 milliohms max), along with a total gate charge characteristic of 60nC.The IRF7809, which uses an advanced trench process, serves as the synchronous MOSFET to minimize Rds(on) while increasing Cdv/dt immunity to prevent spurious turn-on and resulting efficiency loss, according to IR. The IRF7811 is the control MOSFET and uses an advanced planar process to offer low gate charge and facilitate high-frequency switching operation. Available in SO-8 surface mount packages, the new chip set is priced at $1.30 for the pair in quantities of 100,000.
