SC4521
SC4521 is 3A Step-Down Switching Regulator manufactured by SEMTECH.
Description
The SC4521 is a current mode switching regulator with an integrated switch, operating at 600k Hz with programmable soft start and enable functions. The integrated switch allows for cost effective low power solutions (peak switch current 3 amps). High frequency operation allows for very small passive ponents. Current mode operation allows for fast dynamic response and instantaneous duty cycle adjustment as the input varies (ideal for CPE applications where the input is a .. wall plug power). The low shutdown current makes it ideal for portable applications where battery life is important. The SC4521 is an 600k Hz switching regulator with a low pin count. The SC4521 allows customers to use large capacitive loads because its programmable soft start limits the dv/ dt of the output at start up.
Features
Wide operating voltage range: 4.4V to 24V Integrated 3 Amp switch 600k Hz frequency of operation Programmable soft start funchion Current mode control Precision enable threshold SO-8 EDP Lead-free package, fully WEEE and Ro HS pliant
Applications
XDSL modems CPE equipment DC-DC point of load applications Portable equipment Digtial consumer electronics
Typical Application Circuit
D1
1 VIN Enable C3 2 5 8 BST IN EN SS SW 3 6
C1 L1 VOUT
GND 4
FB P
R1 7 D2 R2 C2
C6
C4 R3
Revision: October 5, 2007
.semtech.
POWER MANAGEMENT Absolute Maximum Ratings
Exceeding the specifications below may result in permanent damage to the device, or device malfunction. Operation outside of the parameters specified in the Electrical Characteristics section is not implied. Exposure to Absolute Maximum rated conditions for extended periods of time may affect device reliability.
Parameter Input Supply Voltage Boost Pin Above VSW Boost Pin Voltage EN Pin Voltage
..
Symbol VIN (VBST
- VSW) V BST V EN V FB IFB V SS θJA TJ TSTG TLEAD ESD
Limits -0.3 to +28 16 -0.3 to +32 -0.3 to +24 -0.3 to +6 1 +3 36.5 150 -65 to +150 300...
