Pre-Term is used to program both the precharge current and the termination current threshold, on the BQ2405x. The precharge current level is a factor of two higher than the termination current level. The termination can be set between 5 and 50% of the programmed output current level set by ISET. If left floating the termination and precharge are set internally at 10/20%, respectively. The precharge-to-fast-charge, V_lowv threshold is set to 2.5 V.

Where:

%Term is the percent of fast charge current where termination occurs;
%Pre-CHG is the percent of fast charge current that is desired during precharge;
K_TERM and K_PRE-CHG are gain factors found in the electrical specifications.