Miniature overvoltage clamp protects PMICs in portable applications

July 03, 2012 // By Paul Buckley
Diodes Incorporated has introduced an overvoltage clamp for the protection of power management ICs (PMIC) in portable applications. 

Provided in the small form factor 1.1 mm x 1.4 mm x 0.8 mm W-DFN1114-3 package, the AP9060 is suitable for the latest generation battery-backed products including smart phones, tablets and ultra mobile PCs.

Supporting a wide battery charger output range of 3 V to 30 V, the device will pass the voltage through to the PMIC only up to a safe clamp voltage limit, factory set at 11V.  AP9060's feedback loop maintains the clamped output voltage level by backing off the drive to its p-channel MOSFET switch.  With an ultra low bias current, the device also minimizes self-heating, thereby further increasing product reliability.

In addition, AP9060's use of a low resistance p-channel MOSFET as the pass element ensures that any EMI issues are removed. This is achieved by avoiding noise generation on the input supply circuit normally associated with the charge pump of alternative n-channel MOSFET solutions.

To increase its application flexibility, the AP9060 will also support reverse-current operation, allowing it to pass up to a maximum of 1 A from the PMIC to a load connected to a USB port, therefore meeting the needs of USB On-The-Go (OTG) enabled products.