ZHCSMS4B November 2020 – September 2021 TPS25864-Q1 , TPS25865-Q1
PRODUCTION DATA
The TPS2586x-Q1 is in active mode when VEN is above the precision enable threshold and VSENSE is above its respective UVLO levels. The simplest way to enable the TPS2586x-Q1 is to connect the EN pin to SENSE pin. This connection allows self startup when the input voltage is in the operating range (5.5 V to 26 V) and a UFP detection is made.
In active mode, the TPS25865-Q1 buck regulator does not operate unless CFG1/3 resistors are attached, the TPS25854-Q1 buck regulator operates even though CFG1/3 resistors are not attached. Then the buck regulator operates with Forced Pulse Width Modulation (FPWM), also referred to as Forced Continuous Conduction Mode (FCCM). This operation ensures the buck regulator switching frequency remains constant under all load conditions. FPWM operation provides low output voltage ripple, tight output voltage regulation, and constant switching frequency. Built-in spread-spectrum modulation aids in distributing spectral energy across a narrow band around the switching frequency programmed by the FREQ/SYNC pin. Under light load conditions the inductor current is allowed to go negative. A negative current limit of IL-NEG-LS is imposed to prevent damage to the regulator's low side FET. During operation, the TPS2586x-Q1 synchronizes to any valid clock signal on the FREQ/SYNC input.