Intersil Unveils New DC/DC Converters for Powering Cellphone Amplifiers

Intersil Corp, a provider of high-performance analog semiconductors, has unveiled a new DC/DC converter for powering cell phone RF power amplifiers — ISL9109. The new DC/DC converter is optimized for quick turn-on with only 22 Micro amps of quiescent current.

 

According to Intersil, the new DC/DC converter features excellent transient load response in a compact 2mm x 3mm DFN package. It is a 1.6MHz synchronous step-down regulator specially designed to resolve the inefficiencies that can be seen with mobile RF power amps — particularly at low output levels. The device also features power switches that deliver 1.5A current output. 

 

The ISL9109 that features rapid startup provides light load efficiency while reducing power drawn and thereby maximizing battery life, says company. It operates at 90-95% efficiency in powering an RF PA, when powered from a lithium-ion battery.

 

The ISL9109's supply voltage ranges from 2.7V to 5.5V. This facilitates designers to use a single Li+ cell, three NiMH cells or a regulated 5V input. Its 1.6MHz pulse-width modulation (PWM) switching frequency also requires use of small external components. When in standby mode - its band-gap reference is powered up.

 

Other features of the ISL9109 include soft-start, over current protection, thermal shutdown, 100 percent maximum duty cycle for lowest dropout, peak current limiting with short circuit protection, and over-temperature protection. The converter is also lead-free and RoHS-compliant.

 

The ISL9109 that features small 2mm x 3mm DFN form factor occupies less than one centimeter squared helps in saving space, in any cell phone or modem card design.

 

Intersil's family of power management ICs ranges from building blocks such as charge pumps, to highly-integrated, multiple-output and multiphase PWMs, to quad-voltage hot-swap controllers.

 

Intersil also supplies PWM controller ICs that addresses a broad range of power management requirements for applications that include computing, communications, peripherals, display, networking, telecommunications, industrial, instrumentation and battery-powered products.