MAX8649 Datasheet, PDF (1/31 Pages) Maxim Integrated Products – 1.8A Step-Down Regulator with Differential Remote Sense in 2mm x 2mm WLP

19-4504; Rev 0; 9/09
1.8A Step-Down Regulator with Differential
Remote Sense in 2mm x 2mm WLP
General Description
The MAX8649 high-efficiency DC-to-DC step-down
switching regulator delivers up to 1.8A of output current.
The device operates from a 2.5V to 5.5V input voltage
range, making it future proof for next-generation battery
technologies. The output voltage is I²C programmable
from 0.75V to 1.38V. Fully differential remote sense
ensures precise DC regulation at the load. Total output
error is less than 2% over load, line, and temperature.
The MAX8649 operates at a 3.25MHz fixed frequency.
The high operating frequency minimizes the size of exter-
nal components. The switching frequency of the converter
can be synchronized to the master clock of the applica-
tion. When synchronizing to an external clock, the
MAX8649 measures the frequency of the external clock to
ensure that the clock is stable before changing the
switching frequency to the external clock frequency.
An on-board DAC allows adjustment of the output volt-
age in 10mV steps. The output voltage can be pro-
grammed directly through the I²C interface, or by
preloading a set of on-board registers and using the
two VID logic signals to select the appropriate register.
Other features include internal soft-start control circuitry
to reduce inrush current, output overvoltage, overcur-
rent, and overtemperature protection.
Applications
Cell Phones and Smartphones
PDAs and MP3 Players
+ ^IN1
A1
SNS+
B1
SNS-
C1
V_DD
D1
Pin Configuration
TOP VIEW
(BUMPS ON BOTTOM
AGND
VID1
A2
A3
EN
LX
B2
B3
VID0
PGND
C2
C3
SDA
SCL
D2
D3
IN2
A4
LX
B4
PGND
C4
SYNC
D4
Features
o 1.8A Guaranteed Output Current
o I²C Programmable V_OUT (750mV to 1.38V in 10mV
Steps)
o Operates from 2.5V to 5.5V Input Supply
o On-Chip FET and Synchronous Rectifier
o Fixed 3.25MHz PWM Switching Frequency
o Synchronizes to 13MHz, 19.2MHz, or 26MHz
System Clock when Available
o Small 1.0µH Inductor
o Initial Accuracy 0.5% at 1.25V Output
o 2% Output Accuracy Over Load, Line, and
Temperature
o Power-Save Mode Increases Light Load Efficiency
o Overvoltage and Overcurrent Protection
o Thermal Shutdown Protection
o 400kHz I²C Interface
o < 1µA Shutdown Current
o 16-Bump, 2mm x 2mm WLP Package
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX8649EWE+T -40°C to +85°C
16 Bump WLP
(0.5mm pitch)
+Denotes a lead(Pb)-free/RoHS-compliant package.
Typical Operating Circuit
0V TO
4.0V
2.5V TO
5.5V
0.1μF
11Ω
2.2μF 0.1μF
MAX8649 _IN2
V_DD
LX
SCL
SDA
PGND
IN1
FSYNC
EN
SNS+
VID0
VID1
AGND ^SNS-
1μH
10μF
2.5V TO
5.5V
10μF
0.1μF
V_OUT
0.1μF
(0.75V TO
1.38V)
CPU
WLP 0.5mm PITCH
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.