PL5501  High Efficiency 4-Switch Buck-Boost Controller
1 Features
 Buck-Boost Controller for Step-Up/Step-Down
DC/DC Conversion
 Dynamical programming of Output current and
Output voltage using PWM signal or analog signal  2V to 32 V wide output range
 Comprehensive protection features including
Output Short Protection (OSP), Cycle-by-Cycle
input and output Peak Current Limit, thermal
regulation, thermal shutdown, input UVLO, input
OVP, output OVP etc.  Adjustable Switching Frequency using resistor  Frequency dithering for good EMI performance
 Integrated 2-A MOSFET Gate Drivers
 Input or Output Average Current Limiting with
stable CC loop
 5V/55mA low Iq LDO to power system MCU
 Available in QFN4x4-32 Package
2 Applications
 Automotive Start-Stop Systems
 Industrial PC Power Supplies
 USB Power Delivery
 Car charger  HUB Power
3 Description
    PL5501 is a synchronous 4-switch Buck-Boost controller capable of regulating the output voltage at above or below the input voltage. PL5501 operates over a wide input voltage range of 3.6 V to 32 V (36 V maximum) to support a variety of applications. PL5501 employs Constant ON time control in buck, boost and buck-boost operation modes for superior load and line regulation. The switching frequency could be set to 150kHz, 300kHz, 600kHz or 1200kHz based on different resistor value between FREQ pinand GND pin. The device also features a programmable soft-start function and offers all kinds of protection features including cycle-by-cycle current limiting, input under voltage lockout (UVLO), output over voltage protection (OVP), input Over Voltage Protection, thermal shutdown and output short protection etc. VADJ, IADJ pins are used to program output VBUSvoltage and output current limit, provides voltage control loop, constant current loop, thermal regulation loop, temperature sensing, which makes PL5501 an excellent option for USB Power Delivery (PD) application.
4、Website：www.baitaishengshi.com
5、Typical Application Schematic