EN23F0QI Datasheet, PDF (14/26 Pages) Enpirion, Inc. – 15A Voltage Mode Synchronous Buck PWM

Functional Block Diagram
M/S S_OUT S_IN
BTMP
PG
UVLO
Thermal Limit
Current Limit
Digital I/O
To PLL
Gate Drive
EN23F0QI
PVIN
Linear
Regulator
AVINO
NC(SW)
VOUT
FADJ
(-)
PWM
Comp
(+)
PLL/Sawtooth
Generator
ENABLE
SS
180k
Soft Start
Compensation
Network
(-)
Error
Amp
(+)
Compensation
Network
Power
Good
Logic
300k
Voltage Reference Generator
Band Gap
Reference
BGND
PGND
VDDB
EAIN
VFB
POK
AVIN
AGND
Figure 4: Functional Block Diagram
Functional Description
Synchronous Buck Converter
The EN23F0QI is a highly integrated synchronous,
buck converter with integrated controller, power
MOSFET switches and integrated inductor. The
nominal input voltage (PVIN) range is 4.5V to 14V
and can support up to 15A of continuous output
current. The output voltage is programmed using
an external resistor divider network. The control
loop utilizes a Type IV Voltage-Mode compensation
network and maximizes on a low-noise PWM
topology. Much of the compensation circuitry is
internal to the device. However, a phase lead
capacitor is required along with the output voltage
feedback resistor divider to complete the Type IV
compensation network.. The high switching
frequency of the EN23F0QI enables the use of
small size input and output capacitors, as well as a
wide loop bandwidth within a small foot print.
Protection Features:
The power supply has the following protection
features:
• Programmable Over-Current Protection
• Thermal Shutdown with Hysteresis
• Under-Voltage Lockout Protection
Additional Features:
• Switching Frequency Synchronization
• Programmable Soft-Start
• Power OK Output Monitoring
Power Up Sequence
The EN23F0QI is designed to be powered by either
a single input supply (PVIN) or two separate
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Enpirion Confidential
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