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ROHM Semiconductor |
TECHNICAL NOTE
High-performance Regulator IC Series for PCs
Ultra Low Dropout
Linear Regulators for PC
BD3550HFN, BD3551HFN, BD3552HFN
(0.5~2.0A)
● Description
BD3550HFN,BD3551HFN,BD3552HFN ultra low-dropout linear chipset regulator operates from a very low input supply, and
offers ideal performance in low input voltage to low output voltage applications. It incorporates a built-in N-MOSFET power
transistor to minimize the input-to-output voltage differential to the ON resistance (RON=100mΩ <BD3552HFN>) level. By
lowering the dropout voltage in this way, the regulator realizes high current output (Iomax=2.0A <BD3552HFN>) with
reduced conversion loss, and thereby obviates the switching regulator and its power transistor, choke coil, and rectifier
diode. Thus, BD3550HFN,BD3551HFN,BD3552HFN is designed to enable significant package profile downsizing and cost
reduction. An external resistor allows the entire range of output voltage configurations between 0.65 and 2.7V, while the
NRCS (soft start) function enables a controlled output voltage ramp-up, which can be programmed to whatever power
supply sequence is required.
● Features
1) Internal high-precision reference voltage circuit(0.65V±1%)
2) Built-in VCC undervoltage lockout circuit
3) NRCS (soft start) function reduces the magnitude of in-rush current
4) Internal Nch MOSFET driver offers low ON resistance (100mΩ <BD3552HFN typ>)
5) Built-in current limit circuit
6) Built-in thermal shutdown (TSD) circuit
7) Variable output (0.65~2.7V)
8) Small package HSON8 : 2.9×3×0.6(mm)
9) Tracking function
● Applications
Notebook computers, Desktop computers, LCD-TV, DVD, Digital appliances
● Line-up
It is available to select power supply voltage and maximum output voltage.
Maximum Output Voltage
0.5A
1.0A
2.0A
Package
HSON8
Vcc=5V
BD3550HFN
BD3551HFN
BD3552HFN
Oct. 2008
●Absolute maximum ratings
◎BD3550HFN,BD3551HFN,BD3552HFN
Parameter
Input Voltage 1
Input Voltage 2
Enable Input Voltage
Power Dissipation 1
Power Dissipation 2
Power Dissipation 3
Operating Temperature Range
Storage Temperature Range
Maximum Junction Temperature
Symbol
VCC
VIN
Ven
Pd1
Pd2
Pd3
Topr
Tstg
Tjmax
BD3550HFN
Limit
BD3551HFN
+6.0 *1
+6.0 *1
-0.3~+6.0
0.63 *2
1.35 *3
1.75 *4
-10~+100
-55~+150
+150
BD3552HFN
Unit
V
V
V
W
W
W
℃
℃
℃
*1 Should not exceed Pd.
*2 Reduced by 5.04mW/℃ for each increase in Ta≧25℃ (when mounted on a 70mm×70mm×1.6mm glass-epoxy board, 1-layer)
On less than 0.2% (percentage occupied by copper foil.
*3 Reduced by 10.8mW/℃ for each increase in Ta≧25℃ (when mounted on a 70mm×70mm×1.6mm glass-epoxy board, 1-layer)
On less than 7.0% (percentage occupied by copper foil.
*4 Reduced by 14.0mW/℃ for each increase in Ta≧25℃ (when mounted on a 70mm×70mm×1.6mm glass-epoxy board, 1-layer)
On less than 65.0% (percentage occupied by copper foil.
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