VFM STEP-UP DC/DC CONVERTER WITH
VOLTAGE REGULATOR AND DETECTOR
1
RS5RJ SERIES
OUTLINE
The RS5RJ series are step-up DC/DC converter ICs equipped with a voltage regulator (VR) and a voltage
detector (VD) by CMOS process. Each of these step-up DC/DC converter ICs consists of a VFM DC/DC convert-
er, a linear regulator and a voltage detector. These ICs are output-voltage-fixed type regulators which function
as a linear regulator when input voltage is high, and as step-up DC/DC converter + linear regulator when input
voltage is low, by using an inductor, a diode and a capacitor as external parts for the ICs.
Since a voltage detector is built in these ICs, the potentials such as the output voltage of DC/DC converters can
be monitored.
In addition, these step-up DC/DC converter ICs are suitable for battery-powered and hand-held instruments
because internal circuits can be turned off by the chip enable function so that the standby current can be mini-
mized.
Low Supply Current...........................................TYP. 15A (RS5RJ3624A : V
IN
=3.0V,at no load)
Standby Mode .....................................................Istandby=MAX. 1.0A (RS5RJ
A)
Istandby=MAX. 10.0A (RS5RJ
B)
Low Voltage Operation Possible .......................Operating Voltage V
IN
=1.2V to 10V
High Output Voltage Accuracy .........................Fixed Output Voltage Accuracy2.5%
High Detector Threshold Accuracy...................2.5%
Output Voltage can be set at User's request (refer to Selection Guide).
Voltage close to battery's voltage can be output because these ICs are of a step-up / step-down type
(Ex. a fixed voltage of 3V can be output by a 3V battery).
Built-in Protection Circuits for Lx Driver
Pin for External Driver is equipped, and a large current output can be obtained.
Small Package ....................................................8pin SOP
FEATURES
APPLICATIONS
Power source for cameras, camcorders, and hand-held audio equipment.
Power source for small OA apparatus such as note type personal computers,and word processors.
Power source for hand-held communication appliances such as pagers,cordless telephones, and cellular phones.
2
SELECTION GUIDE
In the RS5RJ Series, the output voltage, the detector threshold, the version symbols, and the taping type for
the ICs can be selected at the user's request.
The selection can be made by designating the part number as shown below:
For example, the product with Output Voltage 5.0V, Detector Threshold 4.5V, Version A, and Taping Type T1,
is designated by Part Number RS5RJ5045A-T1.
RS5RJ
BLOCK DIAGRAM
+
+
+
V
SS
CE
VD
OUT
VD
IN
Vref1
Vref2
VFM
OSC
1
2
3
4
5
6
7
8
L
X
EXT
V
DD
V
OUT
V
LX
Limiter
RS5RJ
Part Number
a b c
d
}
Code
Contens
Setting Output Voltage (V
OUT
):
a
Stepwise setting with a step of 0.6V in the range of 1.5V to 6.0V is possible.
b
Setting Detector Threshold Voltage (V
DET
):
Stepwise setting with a step of 0.1V in the range of 1.2V to 5.0V is possible.
Designation of Version Symbols:
c
A:
Operation of all the internal circuits is stopped by setting CE pin at V
DD
level.
B:
Operation of only Step-up DC/DC converter is stopped by setting CE pin atV
DD
level.
Designation of Taping Type:
d
Ex. 8pin SOP : T1, T2
(refer to Taping Specification)
"T2" is prescribed as a standard.
}
}
4
Topt=25C,Vss=0V
RS5RJ
ABSOLUTE MAXIMUM RATINGS
Symbol
Item
V
DD
Supply Voltage
V
LX
L
X
Pin Voltage
V
EXT
Output Voltage
EXT Pin Voltage
V
OUT
V
OUT
Pin Voltage
VD
OUT
VD
OUT
Pin Voltage
V
CE
Input Voltage
CE Pin Voltage
VD
IN
VD
IN
Pin Voltage
A Version
B Version
I
LX
Inductor Drive Output Current
Lx Pin Current
I
EXT
EXT Pin Current
P
D
Power Dissipation
Topt
Operating Temperature Range
Tstg
Storage Temperature Range
Tsolder
Lead Temperature (Soldering)
Rating
Unit
0.3 to +12
V
Vss0.3 to +12
V
Vss 0.3 to V
DD
+0.3
V
Vss 0.3 to V
DD
+0.3
V
Vss 0.3 to +12
V
Vss 0.3 to V
DD
+0.3
V
Vss 0.3 to V
DD
+0.3
V
Vss 0.3 to +12
250
mA
50
mA
300
mW
30 to +80
C
55 to +125
C
260C, 10s
Absolute Maximum ratings are threshold limit values that must not be exceeded even for an instant under any
conditions. Moreover, such values for any two items must not be reached simultaneously. Operation above
these absolute maximum ratings may cause degradation or permanent damage to the device. These are stress
ratings only and do not necessarily imply functional operation below these limits.
ABSOLUTE MAXIMUM RATINGS