Can pledge FD. Refer to the last note:

For Public Bank Fixed Deposit (FD) customers who opt to apply PB Credit Card secured by FD, the
credit line assigned will be based on the FD pledged amount at a ratio of 1:1. To apply, please
personally submit your application at your FD account holding branch and bring along your FD
certificate for verification and photostat copy of your NRIC (both sides).

Source: http://www.pbebank.com/en/en_content/image...gnature_new.pdf