4A Highly Integrated SupIRBuckTM
IR3897
Single‐Input Voltage, Synchronous Buck Regulator
- 1 -
FEATURES
DESCRIPTION
integrated and highly efficient DC/DC regulator.
The onboard PWM controller and MOSFETs make
IR3897 a space‐efficient solution, providing accurate
power delivery.
The IR3897 SupIRBuckTM is an easy‐to‐use, fully
Single 5V to 21V application
Wide Input Voltage Range from 1.0V to 21V with
external Vcc
Output Voltage Range: 0.5V to 0.86× Vin
Enhanced Line/Load Regulation with Feed‐Forward
Programmable Switching Frequency up to 1.5MHz
Internal Digital Soft‐Start/Soft‐Stop
IR3897 is a versatile regulator which offers
programmability of switching frequency and internal
current limit while operates in wide input and output
voltage range.
Enable input with Voltage Monitoring Capability
The switching frequency is programmable from 300kHz
to 1.5MHz for an optimum solution.
Thermally Compensated Current Limit with robust
hiccup mode over current protection
Smart Internal LDO to improve light load and full load
It also features important protection functions, such as
Pre‐Bias startup, thermally compensated current limit,
over voltage protection and thermal shutdown to give
required system level security in the event of fault
conditions.
efficiency
External Synchronization with Smooth Clocking
Enhanced Pre‐Bias Start‐Up
Precision Reference Voltage (0.5V+/‐0.5%) with
margining capability
Vp for Tracking Applications (Source/Sink Capability
+/‐4A)
APPLICATIONS
Netcom Applications
Integrated MOSFET drivers and Bootstrap Diode
Thermal Shut Down
Embedded Telecom Systems
Server Applications
Programmable Power Good Output with tracking
Storage Applications
capability
Distributed Point of Load Power Architectures
Monotonic Start‐Up
Operating temp: ‐40oC < Tj < 125oC
Small Size: 4mm x 5mm PQFN
Lead‐free, Halogen‐free and RoHS Compliant
BASIC APPLICATION
97
95
93
91
89
87
85
83
81
79
77
12Vin,Internal bias,Frequency 600KHz
2.4 2.8 3.2 3.6 4
75
73
0.4
0.8
1.2
1.6
2
Load Current (A)
1.2Vout
3.3Vout
Figure 2:IR3897 Efficiency
Figure 1: IR3897 Basic Application Circuit
1
June 24, 2014 |DATA SHEET | Rev 3.6