RH5RI521B-T2 [RICOH]
Switching Regulator, Voltage-mode, 0.25A, 100kHz Switching Freq-Max, CMOS, PSSO3, SOT-89, 3 PIN;
| 型号： | RH5RI521B-T2 |
| 厂家： | 
RICOH ELECTRONICS DEVICES DIVISION |
| 描述： | Switching Regulator, Voltage-mode, 0.25A, 100kHz Switching Freq-Max, CMOS, PSSO3, SOT-89, 3 PIN 开关 |
| 文件： | 总24页 (文件大小：210K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
VFM STEP-UP DC/DC CONVERTER
RH5RI××1B/××2B/××3B SERIES
APPLICATION MANUAL
NO.EA-025-0006
VFM STEP-UP DC/DC CONVERTER
RH5RI××1B/××2B/××3B SERIES
OUTLINE
The RH5RI××1B/××2B/××3B Series are VFM (Chopper) Step-up DC/DC converter ICs with ultra low supply
current by CMOS process.
The RH5RI××1B IC consists of an oscillator, a VFM control circuit, a driver transistor (Lx switch), a reference
voltage unit, an error amplifier, resistors for voltage detection, and an Lx switch protection circuit. A low ripple,
high efficiency step-up DC/DC converter can be constructed of this RH5RI××1B IC with only three external com-
ponents, that is, an inductor, a diode and a capacitor.
The RH5RI××2B IC uses the same chip as that employed in the RH5RI××1B IC and is provided with a drive
pin (EXT) for an external transistor instead of an Lx pin, so that a power transistor with a low saturation voltage
can be externally provided, whereby a large current can be caused to flow through the inductor and accordingly a
large current can be obtained. Therefore, the RH5RI××2B IC is recommendable to the user who need a current
as large as several tens mA toseveral hundreds mA.
The RH5RI××3B IC also includes an internal chip enable circuit so that it is possible to set the standby sup-
ply current at MAX. 0.5µA.
These RH5RI××1B/××2B/××3B ICs are suitable for use with battery-powered instruments with low noise
and ultra low supply current.
FEATURES
..........
•
××
Small Number of External Components
Only an inductor, a diode and a capacitor (RH5RI 1B)
...................................
.........................
•
•
•
•
•
Ultra Low Input Current
TYP. 4µA (RH5RI301B/303B at no load,with 1.5V input)
±2.5%
High Output Voltage Accuracy
Low Ripple and Low Noise
......................
Low Start-up Voltage (When the output current is 1mA)
...................................................
MAX. 0.9V
High Efficiency
TYP.80%
..........................
•
•
Low Temperature-Drift Coefficient of Output Voltage
...................................................
TYP. ±50 ppm/˚C
××
××
Small Packages
SOT-89 (RH5RI 1B, RH5RI 2B)
SOT-89-5 (RH5RI××3B)
APPLICATIONS
•
Power source for battery-powered equipment.
•
Power source for cameras, camcorders, VCRs, PDAs, electronic data banks,and hand-held communication
equipment.
•
Power source for appliances which require higher cell voltage than that of batteries used in the appliances.
1
RH5RI
BLOCK DIAGRAM
VLX limiter
Buffer
Vref
–
Lx
LxSW
OUT
Vss
VFM Control
OSC 100kHz
Chip Enable
+
Error Amp.
EXT
CE
............
(Note) Lx Pin
only for RH5RI××1B and RH5RI××3B
only for RH5RI××2B and RH5RI××3B
only for RH5RI××3B
.........
EXT Pin
...........
CE Pin
SELECTION GUIDE
In RH5RI Series, the output voltage, the driver, 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 :
RH5RI×××× – ×× ← Part Number
↑
↑
↑
a b
c
Code
Contents
Setting Output Voltage (VOUT):
a
Stepwise setting with a step of 0.1V in the range of 2.5V to 7.5V is possible.
Designation of Driver:
1B: Internal Lx Tr. Driver (Oscillator Frequency 100kHz)
2B: External Tr. Driver (Oscillator Frequency 100kHz)
3B: Internal Tr./External Tr. (selectively available) (Oscillator Frequency 100kHz, with chip
enable function)
b
c
Designation of Taping type :
Ex. SOT-89 : T1, T2
SOT-89-5 : T1, T2
(refer to Taping Specification)
“T1” is prescribed as a standard.
For example, the product with Output Voltage 5.0V, the External Driver (the Oscillator Frequency 100kHz)
and Taping Type T1, is designated by Part Number RH5RI502B-T1.
2
RH5RI
PIN CONFIGURATION
•
•
SOT-89-5
SOT-89
5
4
(mark side)
2
(mark side)
1 2
1
3
3
××1A/××2B
PIN DESCRIPTION
Pin No.
Symbol
Description
××1B
××2B
××3B
1
2
1
2
5
2
4
3
1
VSS
OUT
Lx
Ground Pin
Step-up Output Pin, Power Supply (for device itself)
Switching Pin (Nch Open Drain)
3
—
3
—
—
EXT
CE
External Tr. Drive Pin (CMOS Output)
Chip Enable Pin (Active Low)
—
3
RH5RI
ABSOLUTE MAXIMUM RATINGS
Vss=0V
Symbol
VOUT
VLX
Item
Rating
+12
Unit
V
Note
Output Pin Voltage
Lx Pin Voltage
+12
V
Note1
Note2
Note3
VEXT
VCE
EXT Pin Voltage
–0.3 to VOUT+0.3
–0.3 to VOUT+0.3
250
V
CE Pin Voltage
V
ILX
Lx Pin Output Current
EXT Pin Current
mA Note1
IEXT
±50
mA Note2
PD
Power Dissipation
500
mW
˚C
Topt
Tstg
Tsolder
Operating Temperature Range
Storage Temperature Range
Lead Temperature (Soldering)
–30 to +80
–55 to +125
260˚C,10s
˚C
(Note 1) Applicable to RH5RI××1A and RH5RI××3B.
(Note 2) Applicable to RH5RI××2B and RH5RI××3B.
(Note 3) Applicable to RH5RI××3B.
ABSOLUTE MAXIMUM RATINGS
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.
4
RH5RI
ELECTRICAL CHARACTERISTICS
• RH5RI301B
VOUT=3.0V
Symbol
VOUT
VIN
Item
Output Voltage
Input Voltage
Conditions
MIN.
TYP.
MAX.
Unit
V
Note
2.925 3.000 3.075
8
V
Vstart
Vhold
Start-up Voltage
Hold-on Voltage
IOUT=1mA,VIN:0→2V
IOUT=1mA,VIN:2→0V
0.8
0.9
V
0.7
V
To be measured at VIN
at no load
IIN1
IIN2
Input Current 1
Input Current 2
4
2
8
5
µA
µA
To be measured at VIN
VIN=3.5V
ILX
Lx Switching Current
Lx Leakage Current
VLX=0.4V
60
80
mA
µA
ILXleak
VLX=6V,VIN=3.5V
0.5
Maximum Oscillator
Frequency
100
120
kHz
fosc
Maxdty
Oscillator Duty Cycle
Efficiency
on (VLX “L” ) side
Lx Switch On
65
70
75
80
85
%
%
V
η
VLXlim
VLX Voltage Limit
0.65
0.8
1.0
Note
Unless otherwise provided, VIN=1.8V, Vss=0V, IOUT=10mA, Topt=25˚C, and use External Circuit of Typical
Application (FIG. 1).
(Note) ILX is gradually increased by the external inductor after Lx Switch is turned ON. In accordance with the increase of ILX, VLX is also increased.
When VLX reaches VLXlim, Lx Switch is turned OFF by Lx Switch Protection Circuit. The time period from the time at which VLX reaches VLXlim to
the time at which Lx Switch is turned OFF is about 3µs.
5
RH5RI
•
RH5RI501B
VOUT=5.0V
Symbol
VOUT
VIN
Item
Output Voltage
Input Voltage
Conditions
MIN.
TYP.
MAX.
Unit
V
Note
4.875 5.000 5.125
8
V
→
Vstart
Vhold
Start-up Voltage
Hold-on Voltage
IOUT=1mA,VIN:0 2V
0.8
0.9
V
→
IOUT=1mA,VIN:2 0V
0.7
V
To be measured at VIN
at no load
IIN1
IIN2
Input Current 1
Input Current 2
6
2
12
5
µA
µA
To be measured at VIN
VIN=5.5V
ILX
Lx Switching Current
Lx Leakage Current
VLX=0.4V
80
80
mA
µA
ILXleak
VLX=6V,VIN=5.5V
0.5
Maximum Oscillator
Frequency
fosc
100
120
kHz
Maxdty
Oscillator Duty Cycle
Efficiency
on (VLX “L” ) side
Lx Switch On
65
70
75
80
85
%
%
V
η
VLX
lim
VLX Voltage Limit
0.65
0.8
1.0
Note2
Unless otherwise provided, VIN=3V, Vss=0V, IOUT=10mA, Topt=25˚C, and use External Circuit of Typical
Application (FIG. 1).
(Note) ILX is gradually increased by the external inductor after Lx Switch is turned ON. In accordance with the increase of ILX, VLX is also increased.
When VLX reaches VLXlim, Lx Switch is turned OFF by Lx Switch Protection Circuit. The time period from the time at which VLX reaches VLXlim to
the time at which Lx Switch is turned OFF is about 3µs.
6
RH5RI
• RH5RI302B
VOUT=3.0V
Conditions
MIN.
TYP.
MAX.
Unit
V
Note
Symbol
VOUT
VIN
Item
Output Voltage
2.925 3.000 3.075
8
Input Voltage
V
→
Vstart
Oscillator Start-up Voltage
Supply Current 1
EXT at no load,VOUT:0 2V
EXT at no load,VOUT=2.88V
EXT at no load,VOUT=3.5V
VEXT=VOUT–0.4V
0.7
30
2
0.8
50
V
IDD
µA
µA
mA
mA
1
2
IDD
Supply Current 2
5
IEXTH
IEXTL
EXT “H” Output Current
EXT “L” Output Current
–1.5
VEXT=0.4V
1.5
80
Maximum Oscillator
Frequency
fosc
100
75
120
85
kHz
%
Maxdty
Oscillator Duty Cycle
VEXT “H” side
65
Unless otherwise provided, VIN=1.8V, Vss=0V, IOUT=10mA, Topt=25˚C, and use External Circuit of Typical
Application (FIG. 2).
• RH5RI502B
VOUT=5.0V
Conditions
MIN.
TYP.
MAX.
Unit
V
Note
Symbol
VOUT
VIN
Item
Output Voltage
4.875 5.000 5.125
8
Input Voltage
V
→
Vstart
Oscillator Start-up Voltage
Supply Current 1
EXT at no load,VOUT:0 2V
EXT at no load,VOUT=4.8V
EXT at no load,VOUT=5.5V
VEXT=VOUT–0.4V
0.7
60
2
0.8
90
5
V
IDD
µA
µA
mA
mA
1
2
IDD
Supply Current 2
IEXTH
IEXTL
EXT “H” Output Current
EXT “L” Output Current
–2
VEXT=0.4V
2
Maximum Oscillator
Frequency
fosc
80
100
75
120
85
kHz
%
Maxdty
Oscillator Duty Cycle
VEXT “H” side
65
Unless otherwise provided, VIN=3V, Vss=0V, IOUT=10mA, Topt=25˚C, and use External Circuit of Typical
Application (FIG. 2).
7
RH5RI
• RH5RI303B
Symbol
VOUT=3.0V
Item
Output Voltage
Input Voltage
Start-up Voltage
Hold-on Voltage
Efficiency
Conditions
MIN.
TYP.
MAX.
Unit
V
Note
VOUT
VIN
2.925 3.000 3.075
8
V
Vstart
Vhold
η
IOUT=1mA,VIN:0→2V
IOUT=1mA,VIN:2→0V
0.8
0.9
V
0.7
70
V
80
4
%
To be measured at VIN
at no load
IIN1
IIN2
Input Current 1
Input Current 2
8
5
µA
To be measured at VIN
VIN=3.5V
µ
A
2
ILX
Lx Switching Current
Lx Leakage Current
EXT “H” Output Current
EXT “L” Output Current
CE “H” Level 1
VLX=0.4V
VLX=6V,VIN=3.5V
VEXT=VOUT–0.4V
VEXT=0.4V
60
mA
µA
mA
mA
V
ILXleak
IEXTH
IEXTL
VCEH1
VCEL1
VCEH2
VCEL2
ICEH
0.5
–1.5
1.5
VOUT≥1.5V
VOUT–0.4
CE “L” Level 1
VOUT≥1.5V
0.4
V
CE “H” Level 2
0.8V≤VOUT<1.5V
0.8V≤VOUT<1.5V
CE=3V
V
OUT–0.1
V
CE “L” Level 2
0.1
0.5
V
CE “H” Input Current
CE “L” Input Current
µA
µA
ICEL
CE=0V
–0.5
80
Maximum Oscillator
Frequency
fosc
100
120
kHz
Maxdty
VLXlim
Oscillator Duty Cycle
VLX Voltage Limit
on (VLX “L” )side
Lx Switch on
65
75
85
%
V
0.65
0.8
1.0
Note
Unless otherwise provided, VIN=1.8V, VSS=0V, IOUT=10mA, Topt=25˚C, and use External Circuit of Typical
Application (FIG. 3).
(Note) ILX is gradually increased by the external inductor after Lx Switch is turned ON. In accordance with the increase of ILX, VLX is also increased.
When VLX reaches VLXlim, Lx Switch is turned OFF by Lx Switch Protection Circuit. The time period from the time at which VLX reaches VLXlim to
the time at which Lx Switch is turned OFF is about 3µs.
8
RH5RI
• RH5RI503B
Symbol
VOUT=5.0V
Item
Output Voltage
Input Voltage
Start-up Voltage
Hold-on Voltage
Efficiency
Conditions
MIN.
TYP.
MAX.
Unit
V
Note
VOUT
VIN
4.875 5.000 5.125
8
V
Vstart
Vhold
η
IOUT=1mA,VIN:0→2V
IOUT=1mA,VIN:2→0V
0.8
0.9
V
0.7
70
V
85
6
%
To be measured at VIN
at no load
IIN1
IIN2
Input Current 1
Input Current 2
12
5
µA
µA
To be measured at VIN
VIN=5.5V
2
ILX
Lx Switching Current
Lx Leakage Current
EXT “H” Output Current
EXT “L” Output Current
CE “H” Level 1
VLX=0.4V
VLX=6V,VIN=5.5V
VEXT=VOUT–0.4V
VEXT=0.4V
80
mA
µA
mA
mA
V
ILXleak
IEXTH
IEXTL
VCEH1
VCEL1
VCEH2
VCEL2
ICEH
0.5
–2.0
2.0
VOUT≥1.5V
VOUT–0.4
CE “L” Level 1
VOUT≥1.5V
0.4
V
CE “H” Level 2
0.8V≤VOUT<1.5V
0.8V≤VOUT<1.5V
CE=5V
V
OUT–0.1
V
CE “L” Level 2
0.1
0.5
V
CE “H” Input Current
CE “L” Input Current
µA
µA
ICEL
CE=0V
–0.5
80
Maximum Oscillator
Frequency
fosc
100
120
kHz
Maxdty
VLXlim
Oscillator Duty Cycle
VLX Voltage Limit
on (VLX “L” )side
Lx Switch on
65
75
85
%
V
0.65
0.8
1.0
Note
Unless otherwise provided, VIN=3V, VSS=0V, IOUT=10mA, Topt=25˚C and use External Circuit of Typical
Application (FIG. 3).
(Note) ILX is gradually increased by the external inductor after Lx Switch is turned ON. In accordance with the increase of ILX, VLX is also increased.
When VLX reaches VLXlim, Lx Switch is turned OFF by Lx Switch Protection Circuit. The time period from the time at which VLX reaches VLXlim to
the time at which Lx Switch is turned OFF is about 3µs.
9
RH5RI
OPERATION OF STEP-UP DC/DC CONVERTER
Step-up DC/DC Converter charges energy in the inductor when Lx Transistor (LxTr) is on, and discharges the
energy with the addition of the energy from Input Power Source thereto, so that a higher output voltage than the
input voltage is obtained.
The operation will be explained with reference to the following diagrams :
< Basic Circuits >
< Current through L >
IL
i2
SD
ILmax
ILmin
IOUT
topen
L
VIN
VOUT
i1
t
Lx Tr
CL
toff
ton
T=1/fosc
Step 1 : LxTr is turned ON and current IL (=i1 ) flows, so that energy is charged in L. At this moment, IL(=i1 )
is increased from ILmin (=0) to reach ILmax in protection to the on-time period (ton) of LxTr.
Step 2 : When LxTr is turned OFF, Schottky diode (SD) is turned on in order that L maintains IL at ILmax, so that
current IL (=i2) is released.
Step 3 : IL (=i2) is gradually decreased, and IL reaches ILmin (=0) after a time period of topen, so that SD is
turned OFF.
In the case of VFM control system, the output voltage is maintained constant by controlling the oscillator fre-
quency (fosc) with the on-time period (ton) being maintained constant.
In the above two diagrams, the maximum value (ILmax) and the minimum value (ILmin) of the current which
flows through the inductor are the same as those when LxTr is ON and also when LxTr is OFF.
The difference between ILmax and ILmin, which is represented by ∆I, is:
..........................................
Equation 1
∆I=ILmax–ILmin=VIN · ton/L=(VOUT–VIN) · topen/L
wherein T=1/fosc=ton+toff
duty (%)=ton/T · 100=ton · fosc · 100
topen≤toff
In Equation 1,VIN · ton/L and (VOUT–VIN) · topen/L are respectively the change in the current at ON, and the
change in the current at OFF.
In the VFM system, topen < toff as illustrated in the above diagram. In this case, the energy charged in the
inductor during the time period of ton is discharged in its entirely during the time period of toff, so that ILmin
becomes zero (ILmin=0).
10
RH5RI
SELECTION OF PERIPHERAL COMPONENTS
When LxTr is on, the energy PON charged in the inductor is provided by Equation 2 as follows :
ton
2
PON=∫0ton (VIN · IL (t)) dt=∫0 (VIN · t/L) dt
2
2
....................................................................................................
=VIN · ton /(2 · L)
Equation 2
In the case of the step-up DC/DC converter, the energy is also supplied from the input power source at the time
of OFF.
Thus, POFF =∫0topen(VIN · IL (t)) dt=∫0topen (VIN · (VOUT–VIN) · t/L)dt
=VIN · (VOUT–VIN) · topen2/(2 · L)
Here, topen=VIN · ton/(VOUT–VIN) from Equation 1, and when this is substituted into the above equation.
3
2
............................................................................
=VIN · ton /(2 · L · (VOUT–VIN))
Input power PIN is (PON+POFF)/T. When this is converted in its entirely to the output.
PIN=(PON+POFF)/T=VOUT · IOUT=POUT .........................................................................
Equation 3
Equation 4
Equation 5 can be obtained as follows by solving Equation 4 for IOUT by substituting Equation 2 and 3 into
Equation 4 :
IOUT=VIN · ton2/(2 · L · T · (VOUT–VIN)
2
2
2
...................................................
=VIN · maxdty /(20000 · fosc · L · (VOUT–VIN))
Equation 5
The peak current which flows through L · LxTr · SD is
..........................................................................................................
ILmax=VIN · ton/L
Equation 6
Therefore, it is necessary that the setting of the input/output conditions and the selection of peripheral compo-
nents be made with ILmax taken into consideration.
HINTS
The above explanation is directed to the calculation in an ideal case where it is supposed that there is no
energy loss in the external components and LxSW. In an actual case, the maximum output current will be 50
to 80% of the above calculated maximum output current. In particular, care must be taken because VIN is
decreased in an amount corresponding to the voltage reduction caused by LxSW when IL is large or VIN is
small. Furthermore, It is required that with respect to VOUT, Vf of the diode (about 0.3V in the case of a
Schottky type diode) be taken into consideration.
When ILX and VLX exceed their respective ratings, use RH5RI××2B and RH5RI××3B ICs with the attach-
ment of an external transistor with a low saturation voltage thereto.
11
RH5RI
TYPICAL CHARACTERISTICS
1) Output Voltage vs. Output Current
RH5RI351B
RH5RI351B
L=82µH
L=120µH
3.0V
4.0
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
3.5
3.0V
3.0
2.0V
1.0V
2.5
1.0V
VIN=0.9V
2.0V
VIN=0.9V
2.0
1.5
1.0
0.5
0
20
40
60
80
100
0
20
40
60
80
100
0
Output Current IOUT(mA)
Output Current IOUT(mA)
RH5RI501B
RH5RI501B
L=82µH
L=120µH
6
5
4
3
2
1
0
6
5
4
3
2
1
0
4.0V
3.0V
4.0V
3.0V
1.5V
1.5V
2.0V
2.0V
VIN=0.9V
VIN=0.9V
0
20
40
60
80
100
0
20
40
60
80
100
Output Current IOUT(mA)
Output Current IOUT(mA)
RH5RI352B
RH5RI502B
L=28µH
3.0V
L=28µH
4.0V
4.0
3.5
3.0
2.5
2.0
1.5
1.0
6
5
4
3
2.0V
1.0V
VIN=0.9V
3.0V
2.0V
VIN=0.9V
1.5V
2
1
0
0.5
0
0
200
400
600
0
200
400
600
Output Current IOUT(mA)
Output Current IOUT(mA)
12
RH5RI
2) Efficiency vs. Output Current
RH5RI351B
RH5RI351B
L=82µH
3.0V
L=120µH
100
90
100
90
80
70
60
50
40
30
20
10
0
80
3.0V
70
2.0V
2.0V
1.0V
VIN=0.9V
60
50
40
30
20
10
0
1.0V
VIN=0.9V
0
20
40
60
80
100
0
20
40
60
80
100
Output Current IOUT(mA)
Output Current IOUT(mA)
RH5RI501B
RH5RI501B
L=120µH
4.0V
L=82µH
4.0V
100
90
80
70
60
100
90
80
70
60
50
40
3.0V
3.0V
1.5V
VIN=0.9V
1.5V
2.0V
2.0V
50
40
VIN=0.9V
30
20
10
0
30
20
10
0
0
20
40
60
80
100
0
20
40
60
80
100
Output Current IOUT(mA)
Output Current IOUT(mA)
RH5RI352B
RH5RI502B
L=28µH
L=28µH
4.0V
100
100
90
80
70
60
50
40
30
20
90
80
70
60
3.0V
3.0V
2.0V
1.0V
VIN=0.9V
2.0V
1.5V
50
40
30
20
VIN=0.9V
10
0
10
0
0
200
400
600
0
200
400
Output Current IOUT(mA)
600
Output Current IOUT(mA)
13
RH5RI
3) Output Current vs.Ripple Voltage
RH5RI351A
RH5RI351B
L=82µH
3.0V
L=120µH
3.0V
120
120
100
80
60
40
20
0
100
80
60
2.0V
1.5V
1.5V
40
2.0V
20
VIN=0.9V
0
VIN=0.9V
20
0
20
40
60
80
100
0
40
60
80
100
Output Current IOUT(mA)
Output Current IOUT(mA)
RH5RI501B
RH5RI501B
L=82µH
4.0V
L=120µH
4.0V
120
100
80
60
40
20
0
140
120
100
80
3.0V
3.0V
60
2.0V
2.0V
40
20
VIN=0.9V
20
VIN=0.9V
20
0
0
0
40
60
80
100
40
60
80
100
Output Current IOUT(mA)
Output Current IOUT(mA)
RH5RI352B
RH5RI502B
L=28µH
3.0V
L=28µH
4.0V
200
180
160
140
120
100
80
250
200
150
100
50
2.0V
1.5V
3.0V
2.0V
60
40
20
VIN=0.9V
VIN=0.9V
100
Output Current IOUT(mA)
0
0
0
200
300
400
0
200
400
600
Output Current IOUT(mA)
14
RH5RI
4) Start-up/Hold-on Voltage vs. Output Current
RH5RI351B
RH5RI501B
L=82µH
L=82µH
1.6
1.4
1.2
1.2
1.0
Vstart
0.8
1.0
0.8
0.6
0.4
0.2
0
Vstart
0.6
Vhold
0.4
Vhold
0.2
0
5
0
10
15
0
5
10
15
Output Current IOUT(mA)
Output Current IOUT(mA)
RH5RI352B
RH5RI502B
L=28µH
L=28µH
2.5
2.5
2.0
1.5
1.0
0.5
0
2.0
1.5
1.0
Vstart
Vhold
Vstart
Vhold
0.5
0
0
100
150
200
50
150
Output Current IOUT(mA)
200
0
50
100
Output Current IOUT(mA)
5) Output Voltage vs. Temperature
6) Start-up Voltage vs. Temperature
RH5RI501B
RH5RI501B
5.20
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
5.15
5.10
5.05
5.00
4.95
4.90
4.85
4.80
–40
–20
0
20
40
60
80
–40 –20
0
20
40
60
80
Temperature Topt(˚C)
Temperature Topt(˚C)
15
RH5RI
7) Hold-on Voltage vs. Temperature
8) Supply Current 1 vs.Temperature
RH5RI501B
RH5RI502B
60
0.8
50
0.7
0.6
0.5
40
30
20
10
0
0.4
0.3
0.2
–40
–20
0
20
40
60
80
–40
–20
0
20
40
60
80
Temperature Topt(˚C)
Temperature Topt(˚C)
10) Lx Switching Current vs.Temperature
9) Input Current 2 vs.Temperature
RH5RI501B
RH5RI501B
1.8
200
180
160
140
120
100
80
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
60
40
20
0
–40
–20
0
20
40
60
80
–40 –20
0
20
40
60
80
Temperature Topt(˚C)
Temperature Topt(˚C)
11) Lx Leakage Current vs.Temperature
12) Maximum Oscillator Frequency vs.Temperature
RH5RI501B
RH5RI501B
160
0.30
140
120
100
80
0.25
0.20
0.15
0.10
0.05
0
60
40
20
0
–40
–20
0
20
40
60
80
–40
–20
0
20
40
60
80
Temperature Topt(˚C)
Temperature Topt(˚C)
16
RH5RI
13) Oscillatar Duty Cycle vs. Temperature
14) Vlx Voltage Limit vs. Temperature
RH5RI501B
RH5RI501B
100
1.00
0.95
0.90
90
80
70
60
50
0.85
0.80
0.75
0.70
0.65
0.60
0.55
0.50
–40
–20
0
20
40
60
80
–40
–20
0
20
40
60
80
Temperature Topt(˚C)
Temperature Topt(˚C)
15) Output Current vs. Temperature
16) Output Current vs. Temperature
RH5RI502B
RH5RI502B
5.0
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
–20
0
20
40
60
80
–40
–40
–20
0
20
Temperature Topt(˚C)
40
60
80
Temperature Topt(˚C)
17
RH5RI
TYPICAL APPLICATIONS
• RH5RI××1B
Diode
Inductor
VOUT
Lx
OUT
Vss
+
VIN
Capacitor
Components Inductor (L)
Diode (D)
: 82µH (Sumida Electric Co., Ltd.)
: MA721 (Matsushita Electronics Corporation, Schottky Type)
Capacitor (CL) : 22µF (Tantalum Type)
FIG. 1
• RH5RI××2B
Inductor
Diode
VOUT
Cb
Rb
OUT
EXT
Vss
+
VIN
Capacitor
Tr
Components Inductor (L)
Diode (D)
: 28µH (Troidal Core)
: HRP22 (Hitachi, Schottky Type)
: 100µF (Tantalum Type)
: 2SD1628G
Capacitor (CL)
Transistor (Tr)
Base Resistor (Rb)
: 300Ω
Base Capacitor (Cb) : 0.01µF
FIG. 2
18
RH5RI
• RH5RI××3B
Diode
Inductor
VOUT
Lx
OUT
NC
EXT
CE
Vss
+
VIN
Capacitor
Components Inductor (L)
Diode (D)
: 82µH (Sumida Electric Co., Ltd.)
: MA721 (Matsushita Electronics Corporation, Schottky Type)
Capacitor (CL) : 22µF (Tantalum Type)
FIG. 3
Inductor
Diode
VOUT
NC
Lx
Cb
OUT
EXT
CE Vss
+
VIN
Rb
Capacitor
Tr
Components Inductor (L)
Diode (D)
: 28µH (Troidal Core)
: HRP22 (Hitachi, Schottky Type)
: 100µF (Tantalum Type)
: 2SD1628G
Capacitor (CL)
Transistor (Tr)
Base Resistor (Rb) : 300Ω
Base Capacitor (Cb) : 0.01µF
FIG. 4
19
RH5RI
• CE pin Drive Circuit
Diode
Inductor
RH5RI××3B
VOUT
Lx
OUT
NC
EXT
CE
Vss
Pull-up
resistor
+
Capacitor
VIN
CE
Tr
FIG. 5
20
RH5RI
APPLICATION CIRCUITS
• 12V Step-up Circuit
Inductor
Diode
VOUT
ZD:6.8V
RH5RI502B
Cb
Rb
OUT
+
Capacitor
VIN
EXT
Vss
RZD
Tr
Starter Circuit
(Note) When the Output Current is small or the Output Voltage is unstable,use the Rzd for flowing the bias current through the Zener diode ZD.
FIG. 6
• Step-down Circuit
Inductor
VOUT
PNP
Tr
Diode
RH5RI××1B
OUT
Rb2
Lx
VIN
Rb1
+
Vss
Capacitor
Starter Circuit
(Note) When the Lx pin Voltage is over the rating at the time PNP Tr is OFF,use a RH5RI××2B and drive the PNP Tr. by the external NPN Tr.
FIG. 7
21
RH5RI
• Step-up/Step-down Circuit with Flyback
Diode
VOUT
Trance1:1
RH5RI××1B
OUT
Lx
VIN
+
Vss
Capacitor
Starter Circuit
(Note) Use a RH5RI××2B,depend on the Output Current.
FIG. 8
The Starter Circuit is necessary for all above circuits.
*
1.For Step-up Circuit.
VOUT side
VIN side
Starter Circuit
1.For Step-down and Step-up/Step-down Circuit.
VIN side
VOUT side
Tr
RST
Starter Circuit
ZDST
ZDst 2.5V≤ZDST≤Designation of Output Voltage
Rst Input Bias Current of ZDST and Tr.
(several kΩ to several hundreds kΩ)
22
RH5RI
APPLICATION HINTS
When using these ICs, be sure to take care of the following points :
• Set external components as close as possible to the IC and minimize the connection between the com-
ponents and the IC. In particular, when an external component is connected to OUT Pin, make mini-
mum connection with the capacitor.
• Make sufficient grounding. A large current flows through Vss Pin by switching. When the impedance
of the Vss connection is high, the potential within the IC is varied by the switching current. This
mayresult in unstable operation of the IC.
• Use capacitor with a capacity of 10µF or more, and with good high frequency characteristics such as
tantalum capacitor. We recommend the use of a capacitor with an allowable voltage which is at least
three times the output set voltage. This is because there may be the case where a spike-shaped high
voltage is generated by the inductor when Lx transistor is turned off.
• Take the utmost care when choosing an inductor. Namely, choose such an inductor that has sufficient-
ly small d.c. resistance and large allowable current, and hardly reaches magnetic saturation. When
the inductance value of the inductor is small, there may be the case where ILX exceeds the absolute
maximum ratings at the maximum load. Use an inductor with an appropriate inductance (refer to
Selectionof peripheral components).
• Use a diode of a Schottky type with high switching speed, and also take care of the rated current (refer
to Selection of peripheral components).
The performance of power source circuits using these ICs largely depends upon the peripheral components. Take the utmost care
in the selection of the peripheral components. In particular, design the peripheral circuits in such a manner that the values such as volt-
age, current and power of each component, PCB patterns and the IC do not exceed their respective rated values.
23
相关型号：
SI9130DB
5- and 3.3-V Step-Down Synchronous ConvertersWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9135LG-T1
SMBus Multi-Output Power-Supply ControllerWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9135LG-T1-E3
SMBus Multi-Output Power-Supply ControllerWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9135_11
SMBus Multi-Output Power-Supply ControllerWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9136_11
Multi-Output Power-Supply ControllerWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9130CG-T1-E3
Pin-Programmable Dual Controller - Portable PCsWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9130LG-T1-E3
Pin-Programmable Dual Controller - Portable PCsWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9130_11
Pin-Programmable Dual Controller - Portable PCsWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9137
Multi-Output, Sequence Selectable Power-Supply Controller for Mobile ApplicationsWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9137DB
Multi-Output, Sequence Selectable Power-Supply Controller for Mobile ApplicationsWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9137LG
Multi-Output, Sequence Selectable Power-Supply Controller for Mobile ApplicationsWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9122E
500-kHz Half-Bridge DC/DC Controller with Integrated Secondary Synchronous Rectification DriversWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
©2020 ICPDF网 联系我们和版权申明