BD3504FVM_08 Datasheet, PDF (1/17 Pages) Rohm – Ultra Low Dropout Linear Regulator Controllers for PC Chipsets

TECHNICAL NOTE
High-performance Regulator IC Series for PCs
Ultra Low Dropout
Linear Regulator Controllers
for PC Chipsets
BD3504FVM, BD3500FVM, BD3501FVM, BD3502FVM
●Description
The BD3500/01/02/04FVM is an ultra-low dropout linear regulator controller for chipset that can achieve ultra-low voltage
input to ultra-low voltage output. By using N-MOSFET for external power transistor, the controller can be used at ultra-low
I/O voltage difference up to voltage difference generated by ON resistance. In addition, because best suited power
transistor can be chosen in accord with the output current, downsizing and cost reduction of the set can be achieved.
Because by reducing the I/O voltage difference, large current output is achieved and conversion loss can be reduced,
switching power supply can be replaced. BD3500/01/02/04FVM does not need any choke coil, diode for rectification and
power transistor which are required for switching power supply, total cost of the set can be reduced and compact size can
be achieved for the set. Using external resistors, optional output from 0.65V to 2.5V can be set. In addition, since voltage
output start-up time can be adjusted by using the NRCS terminal, it is possible to flexibly meet the power supply sequence
of the set.
●Features
1) Reduced rush current by NRCS
2) Built-in driver for external Nch h transistor
3) Adoption of MSOP8 package: 2.9 x 4.0 x 0.9 (mm)
4) Built-in timer latch short protection circuit
5) Built-in low input maloperation prevention circuit
6) Output voltage variable type
7) Built-in overheat protection circuit
●Applications
Mobile PC, desktop PC, digital home appliances
●Line up
Parameter
Output Voltage
NRCS
(Soft start)
Timer latch short
protection circuit
VIN UVLO
External FET
GATE Drive Current
BD3500FVM
1.8V (Fix)
○
(Independent Setting)
○
(Independent Setting)
Hysterisis
+1/-3mA
BD3501FVM
1.5V (Fix)
○
(Independent Setting)
○
(Independent Setting)
Hysterisis
+1/-3mA
BD3502FVM
1.2V (Fix)
○
(Independent Setting)
○
(Independent Setting)
Hysterisis
+1/-3mA
BD3504FVM
Variable(0.65～2.5V)
○
(Same Timer Latch)
○
(Same NRCS)
Detected at start-up only
(set by external resistor)
+3/-3mA
Oct. 2008