TECHNICAL NOTE

High-performance Regulator IC Series for PCs

Ultra Low Dropout

Linear Regulators(4A) for Desktop PC

BD3522EFV, BD35221EFV, BD35222EFV

● Description

BD3522EFV / BD35221EFV / BD35222EFV ultra low-dropout linear chipset regulator operates from a very low input supply,

and offers ideal performance in low input voltage to low output voltage applications. It incorporates a built-in N-MOSFET

dropout voltage in this way, the regulator realizes high current output (Iomax=4.0A) with reduced conversion loss, and

thereby obviates the switching regulator and its power transistor, choke coil, and rectifier diode. Thus, BD3522EFV /

BD35221EFV / BD35222EFV designed to enable significant package profile downsizing and cost reduction. In BD3522EFV,

an external resistor allows the entire range of output voltage configurations between 0.65 and 2.7V, while the NRCS (soft

start) function enables a controlled output voltage ramp-up, which can be programmed to whatever power supply sequence

is required.

● Features

1) Internal high-precision reference voltage circuit(0.65V±1%)

2) Internal high-precision output voltage circuit <BD35221EFV/BD35222EFV>

3) Built-in VCC undervoltage lockout circuit (VCC=3.80V)

4) NRCS (soft start) function reduces the magnitude of in-rush current

5) Internal Nch MOSFET driver offers low ON resistance (28mΩ typ)

6) Built-in short circuit protection (SCP)

7) Built-in current limit circuit (4.0A min)

8) Built-in thermal shutdown (TSD) circuit

9) Variable output

(0.65～2.7V) <BD3522EFV>

10) High-power package HTSSOP-B20 : 6.5mm x 6.4mm x 1.0mm

11) Tracking function

● Applications

Notebook computers, Desktop computers, LCD-TV, DVD, Digital appliances

● Line-up

Maximum Output Voltage

Package

Product name

Adjustable (0.65～2.7V)

HTSSOP-B20

BD3522EFV

1.2V (fixed)

BD35221EFV

1.5V (fixed)

BD35222EFV

Oct. 2008