EP53F8QI Datasheet, PDF (7/11 Pages) Enpirion, Inc. – 1500 mA Synchronous Buck PWM DC-DC Converter with Integrated Inductor

Functional Block Diagram
POK
PVIN
EP53F8QI
ENABLE
UVLO
Thermal Limit
Current Limit
Soft Start
(-)
PWM
Comp
(+)
Sawtooth
Generator
POK
Logic
P-Drive
N-Drive
Compensation
Network
NC (SW)
VOUT
PGND
(-)
VFB
Error
Amp
(+)
VREF
DAC
BIAS
AVIN
Package Boundary
Figure 4: Functional Block Diagram
Functional Description
The EP53F8QI leverages advanced CMOS
technology to provide high switching
frequency, while also maintaining high
efficiency.
Packaged in a 3 mm x 3 mm x 1.1 mm QFN,
the EP53F8QI provides a high degree of
flexibility in circuit design while maintaining a
very small footprint. High switching frequency
allows for the use of very small MLCC input
and output filter capacitors.
The converter uses voltage mode control to
provide high noise immunity, low output
impedance and excellent load transient
response. Most compensation components are
integrated into the device, requiring only a
single external compensation capacitor.
Output voltage is programmed via an external
resistor divider. Output voltage can be
programmed from 0.6V to V_IN-V_DROPOUT.
POK monitors the output voltage and signals if
it is within ±10% of nominal. Protection
features include under voltage lockout (UVLO),
over current protection, short circuit protection,
and thermal overload protection.
Stability over Wide Range of Operating
Conditions
The EP53F8QI utilizes an internal
compensation network and is designed to
provide stable operation over a wide range of
operating conditions. To improve transient
performance or reduce output voltage ripple
with dynamic loads you have the option to add
supplementary capacitance to the output. The
EP53F8QI is stable with up to 60 µF of output
capacitance without compensation adjustment.
Additional output capacitance above 60 µF can
be accommodated with compensation
adjustment depending on the application. The
high switching frequency allows for a wide
control loop bandwidth.
©Enpirion 2009 all rights reserved, E&OE
7
www.enpirion.com
01542
4/3/2009
Rev:A