资 源 简 介
The ISL97522 represents a 4-channel supply control IC foruse in large panel TFT-LCD displays. SupporTIng inputs from4.5V to 13V, the ISL97522 includes a boost controller toachieve the required AVDD output voltage. Both VON andVOFF are generated using off-chip charge-pumps which arethen post regulated using on-board LDO controllers.The logic supply is generated using an internal nonsynchronousbuck controller. This controller runs at 180° outof phase with the AVDD supply to minimize input noise.The AVDD, VOFF, and VON outputs are automaTIcallysequenced as AVDD, VOFF, and VON. By using an opTIonalexternal series transistor with AVDD (Q1), the start-upsequence can be adjusted to VOFF, AVDD and then VON. AVON slicing circuit is also included to reduce LCD flicker.The ISL97522 also incorporates a fault protecTIon circuit thatcan disable the IC and turn off all outputs when an outputshort is detected. (Note that to protect AVDD a singleexternal transistor is required).
