R1245S003C-E2-FE [RICOH]
Switching Regulator, Current-mode, 2.7A, 550kHz Switching Freq-Max, CMOS, PDSO8, ANTIMONY AND HALOGEN FREE, ROHS COMPLIANT, HSOP-8;
| 型号： | R1245S003C-E2-FE |
| 厂家： | 
RICOH ELECTRONICS DEVICES DIVISION |
| 描述： | Switching Regulator, Current-mode, 2.7A, 550kHz Switching Freq-Max, CMOS, PDSO8, ANTIMONY AND HALOGEN FREE, ROHS COMPLIANT, HSOP-8 开关 光电二极管 输出元件 |
| 文件： | 总38页 (文件大小：960K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
R1245x SERIES
1.2A, 30V Step Down DC/DC converter
NO.EA-269-130322
OUTLINE
The R1245x series are CMOS-based Step-down DC/DC converter with internal N-channel high side Tr. The
ON resistance of the built-in high-side transistor is 0.35Ω and the R1245 can provide the maximum 1.2A output
current. Each of the ICs consists of an oscillator, a PWM control circuit, a voltage reference unit, an error
amplifier, a phase compensation circuit, a slope compensation circuit, a soft-start circuit, protection circuits, an
internal voltage regulator, and a switch for bootstrap circuit. The ICs can make up a step-down DC/DC converter
with an inductor, resistors, a diode, and capacitors.
The R1245x series are current mode operating type DC/DC converters without an external current sense
resistor, and realizes fast response and high efficiency. As an output capacitor, a ceramic type capacitor can be
used with the R1245X series. The options of the internal oscillator frequency are preset at 330kHz for version A
and B, 500kHz for version C and D, 1000kHz for version E and F, 2400kHz for version G and H.
As for protection, an Lx peak current limit circuit cycle by cycle, a thermal shutdown function and an under
voltage lockout (UVLO) function are built in. Furthermore, there are two types for short protection, for A/C/E/G
version, a latch protection function which makes the output latch off if the output voltage keeps lower than the set
output voltage for a certain time after detecting current limit is built in, for B/D/F/H version, a fold-back protection
function which changes the oscillator frequency slower after detecting short circuit or equivalent.
As for the packages of the R1245 series, HSOP-8E, DFN(PLP)2020-8, SOT23-6W are available.
FEATURES
● Operating Voltage ················································ 4.5V~30V
● Internal N-channel MOSFET Driver························· RON=0.35Ω Typ.
● Adjustable output voltage with external resistor ······ 0.8V or more
● Feedback voltage and tolerance ····························· 0.8V±1.0%
● Peak current limit····················································· Typ. 2.0A
● UVLO function released voltage······························ Typ. 4.0V
● Operating frequency················································ 330kHz (A/B version), 500kHz (C/D version),
1000kHz (E/F version), 2400kHz (G/H version)
● Fold-back protected frequency································ 170kHz (B/D version), 250kHz (F version),
400kHz (H version)
● Latch protection delay time······································ Typ. 4ms for A/C/E/G version
● Ceramic capacitors recommended for input and output.
● Stand-by current ······················································ Typ. 0μA
● Packages································································· SOT-23-6W, DFN(PLP)2020-8, HSOP-8E
APPLICATIONS
● Power source for digital home appliance such as digital TV, DVD players.
● Power source for 5V PSU or 2-cell or more Li-ion battery powered communication equipment, cameras,
video instruments such as VCRs, camcorders.
● Power source for high voltage battery-powered equipment.
● Power source for office equipment such as printers and fax machines.
1
R1245x
BLOCK DIAGRAMS
V IN
Thermal Shutdown
5V
CE
UVLO
Regulator
Regulator
BST
Shutdown
SETPULSE
S
D
Oscil lator
*1
FB
Lx
MAXDUTY
R
-
+
Reference
-
+
Soft Start
0.8V
Circuit(1ms)
Limit Latch
Circuit (4ms)
*1
Current Slope
Circui
t
GND
Peak Current
Limit Circuit
*1
Version
Oscillator frequency
Short protection type
A
B
C
D
E
F
330kHz
330kHz
500kHz
500kHz
1000kHz
1000kHz
2400kHz
2400kHz
Latch
Fold-back
Latch
Fold-back
Latch
Fold-back
Latch
G
H
Fold-back
2
R1245x
SELECTION GUIDE
In the R1245x Series, the package, type of short protection (Latch or Fold back), and the oscillator frequency
can be selected with the user’s request.
Product code
R1245S003∗-E2-FE
R1245K003∗-TR
Package
HSOP-8E
Quantity per reel
1,000
Pb free
Yes
Halogen free
Yes
Yes
DFN(PLP)2020-8
5,000
Yes
SOT-23-6W
3,000
Yes
Yes
R1245N001∗-TR-FE
∗: Designation of the oscillator frequency and the protection function option.
Oscillator
frequency
Latch
protection
Fold back
protection
Symbol
A
B
C
D
E
F
330kHz
330kHz
500kHz
500kHz
1000kHz
1000kHz
2400kHz
2400kHz
9
9
9
9
9
9
9
9
G
H
3
R1245x
PIN CONFIGURATION
• DFN(PLP)2020-8
Bottom View
6 7 8
Top View
7 6
8
5
5
1
2
3
4
4
3
2
1
• HSOP-8E
Bottom View
• SOT-23-6W
Top View
Top View
8
7
6
5
5
6 7 8
6
5
4
1
2
3
1
2
3
4
4
3 2 1
*Connect the backside heat radiation tub to GND or same as GND level (recommendation). The tub is connected
to the GND pin.
PIN DESCRIPTION
z R1245S(HSOP-8E)
Pin No.
Symbol
LX
Description
1
2
3
4
5
6
7
8
LX Switching Pin
Power Supply Pin
VIN
CE
Chip Enable Pin (Active with ”H”)
TEST pin (must be open for user side.)
Ground Pin
TEST
GND
FB
Feedback Pin
NC
No connection
BST
Bootstrap Pin
*Connect the backside heat radiation tub to GND or same as GND level (recommendation). The tub is connected
to the GND pin.
4
R1245x
z R1245K (DFN(PLP)2020-8)
Pin No.
Symbol
LX
Description
1
2
3
4
5
6
7
8
LX Switching Pin
Power Supply Pin
Power Supply Pin
VIN
VIN
CE
Chip Enable Pin (Active with ”H” )
Ground Pin
GND
FB
Feedback Pin
TEST
BST
Test Pin ( must be open for user side.)
Bootstrap Pin
*Connect the backside heat radiation tub to GND or same as GND level (recommendation). The tub is connected
to the GND pin.
z R1245N (SOT23-6W)
Pin No.
Symbol
BST
GND
FB
Description
1
2
3
4
5
6
Bootstrap Pin
Ground Pin
Feedback Pin
CE
Chip Enable Pin (Active with ”H” )
Power Supply Pin
VIN
LX
LX Switching Pin
ABSOLUTE MAXMUM RATINGS
(GND=0V)
Symbol
VIN
Item
Rating
-0.3 to 32.0
Unit
Input Voltage
V
V
V
V
V
V
VBST
VLX
BST Pin Voltage
LX Pin Voltage
VLX-0.3 to VLX+6.0
-0.3 to VIN+0.3
-0.3 to VIN+0.3
-0.3 to VIN+0.3
-0.3 to 6.0
VCE
CE Pin Input Voltage
CE Pin input Voltage
Feedback Pin Voltage
VCE
VFB
HSOP-8E
Standard Land Pattern*
2900
880
PD
Power Dissipation DFN(PLP)2020-8
SOT-23-6W
Standard Land Pattern*
Standard Land Pattern*
mW
430
Ta
Operating Temperature Range
Storage Temperature Range
-40 to 105
-55 to 125
ºC
ºC
Tstg
*For Power Dissipation, refer to the PACKAGE INFORMATION on the web site.
ABSOLUTE MAXIMUM RATINGS
Electronic and mechanical stress momentarily exceeded absolute maximum ratings may cause the permanent
damages and may degrade the lifetime and safety for both device and system using the device in the field.
The functional operation at or over these absolute maximum ratings is not assured.
5
R1245x
ELECTRICAL CHARACTERISTICS
(Unless otherwise specified, VIN= 12V, Ta=25ºC)
Symbol
VIN
Item
Conditions
MIN.
TYP. MAX. Unit
4.5
30
V
Operating Input Voltage
VIN Consumption Current
IIN
0.5
1.0
mA
VIN=30V, VFB=1.0V
VUVLO2 VUVLO2
Specified VIN falling
edge
VUVLO1
VUVLO2
3.6
3.8
V
V
UVLO Detect Voltage
-0.2
-0.1
4.0
4.2
UVLO Released Voltage
Specified rising edge
VFB
0.792 0.800 0.808
±100
V
VFB Voltage Tolerance
∆VFB/∆T
ppm/ºC
VFB Voltage Temperature Coefficient
-40ºC ≤ Ta ≤ 105ºC
Version A/B
Version C/D
Version E/F
Version G/H
Version B/D
300
450
900
330
500
360
550
fosc
kHz
kHz
Oscillator Frequency
1000
1100
2600
2200 2400
170
fFLB
Fold back Frequency
VFB<0.56V
Version F
250
400
Version H
Version A/B/C/D
Version E/F
92
88
76
1
Maxduty
%
Oscillator Maximum. Duty Cycle
Version G/H
tSS
tDLY
ms
ms
Ω
Soft-start Time
VFB=0.72V
4
Delay Time for Latch Protection
LX High Side Switch ON Resistance
Version A/C/E/G
VBST-VLX=4.5V
RLXH
ILXHOFF
ILIMLXH
VCEL
VCEH
IFB
0.35
0
5
μA
A
LX High Side Switch Leakage Current VIN=30V, VCE=0V
1.5
2.0
2.7
0.3
LX High Side Switch Limited Current
CE “L” Input Voltage
VBST-VLX=4.5V
VIN=30V
V
1.6
-1.0
-1.0
-1.0
V
CE “H” Input Voltage
VFB Input Current
VIN=30V
1.0
1.0
1.0
μA
μA
μA
VIN=30.0V, VFB=1.0V
VIN=30V, VCE=0V
VIN=30V, VCE=30V
ICEL
CE “L” Input Current
ICEH
CE “H” Input Current
Thermal Shutdown Detect
Temperature
TTSD
160
0
ºC
Hysteresis 30ºC
VIN=30V
Istandby
5
μA
Standby Current
RECOMMENDED OPERATING CONDITIONS (ELECTRICAL CHARACTERISTICS)
All of electronic equipment should be designed that the mounted semiconductor devices operate within the
recommended operating conditions. The semiconductor devices cannot operate normally over the recommended
operating conditions, even if when they are used over such conditions by momentary electronic noise or surge. And the
semiconductor devices may receive serious damage when they continue to operate over the recommended operating
conditions.
6
R1245x
TYPICAL APPLICATION
R1245x00xA/B 330kHz VOUT=1.2V VIN=24V
V
IN
V
IN
BST
24V
R1
6kΩ
C
BST
C
470pF
SPD
C
10µF
IN
0.47µF
L 10µH
FB
Lx
C
47µF
OUT
D
R2
12kΩ
TEST
CE
R
CE
“H”active
10kΩ
GND
(recommended)
R1245x00xC/D 500kHz VOUT=3.3V VIN=24V
V
24V
IN
V
IN
BST
C
SPD
C
BST
R1
3.75kΩ
C
10µF
IN
1000pF
0.47µF
L 10µH
FB
Lx
C
22µF
OUT
D
R2
1.2kΩ
TEST
CE
RCE
“H”active
10kΩ
(recommended)
GND
*TEST pin must be open.
7
R1245x
R1245x00xE/F 1000kHz VOUT=3.3V VIN=12V
V
IN
12V
V
IN
BST
C
470pF
SPD
R1
3.75kΩ
C
BST
CIN
0.47µF
4.7µF
L 4.7µH
FB
Lx
C
10µF
OUT
D
R2
TEST
CE
1.2kΩ
RCE
“H”active
10kΩ
(recommended)
GND
R1245x00xG/H 2400kHz VOUT=5.0V VIN=12V
V
IN
V
IN
BST
12V
C
470pF
SPD
C
BST
R1
6.3kΩ
CIN
0.47µF
L 2.2µH
2.2µF
FB
Lx
C
4.7µF
OUT
D
R2
1.2kΩ
TEST
CE
R
10kΩ
CE
“H”active
GND
(recommended)
*TEST pin must be open.
TECHNICAL NOTES
*External components must be connected as close as possible to the ICs and make wiring as short as possible.
Especially, the capacitor connected in between VIN pin and GND pin must be wiring the shortest. If their
impedance is high, internal voltage of the IC may shift by the switching current, and the operating may be
unstable. Make the power supply and GND lines sufficient. In the wiring of the power supply, GND, LX, VOUT and
the inductor, large current by switching may flow. To avoid the bad influence, the wiring between the resistance,
“Rup” for setting the output voltage and loading, and the wiring between the inductor and loading must be
separated.
*The ceramic capacitors have low ESR (Equivalent Series Resistance) and recommended for the ICs. The
recommendation of CIN capacitor between VIN and GND is 10μF or more for A/B/C/D version, 4.7μF or more for
E/F version, and 2.2μF or more for G/H version. Verify the bias dependence and the temperature characteristics
of the ceramic capacitors. Recommendation conditions are written based on the case which the
recommendation parts are used with the R1245.
*The R1245 series are designed with the recommendation inductance value and ceramic capacitor value and
phase compensation has been made. If the inductance value is large, due to the lack of current sensing amount
of the current mode, unstable operation may result. On the contrary, if the inductance value is small, the current
sensing amount may increase too much, low frequency oscillation may occur when the on duty ratio is beyond
8
R1245x
50%. Not only that, if the inductance value is small, according to the increase of the load current, the peak
current of the switching may increase, as a result, the current may reach the current limit value and the current
limit may work.
*As for the diode, use the Schottky diode with small capacitance between terminals. The reference characteristic
of the capacitance between terminals is around 100pF or less at 10V. If the capacitance between terminals is
large, excess switching current may flow and the operation of the IC may be unstable. If the capacitance
between terminals of the Scottky diode is beyond 100pF at 10V or unknown, verify the load regulation, line
regulation, and the load transient response.
*Output voltage can be set by adjustment of the values of R1 and R2. The equation of setting the output voltage
is VOUT=VFB × (R1+R2)/R2. If the values of R1 and R2 are large, the impedance of FB pin increases, and pickup
the noise may result. The recommendation value range of R2 is approximately between 1.0kΩ to 16kΩ. If the
operation may be unstable, reduce the impedance of FB pin.
*For the CE pin, as an ESD protection element, a diode to VIN pin is formed internal of the IC. If CE pin voltage
may become higher than VIN pin voltage, to prevent flowing large current from CE pin to VIN pin, connect 10kΩ or
more resistor between CE and VIN pin.
*Connect the backside heat radiation tub of the DFN(PLP)2020-9/HSOP-8E to the GND. As for multi-layered
boards, to make better power dissipation, putting some thermal vias on the thermal pad in the land pattern and
radiation of the heat to another layer is effective.
*After the soft-start operation, the latch function is enabled for version A/C/E/G. The latch protection starts the
internal counter when the internal current limit protection circuit detects the current limit. When the internal
counter counts up to the latch timer limit, typically 4ms, the output is latched off. To reset the latch function, make
the CE pin “L”, or make VIN pin voltage lower than UVLO detector threshold. Then in the case that the output
voltage or FB voltage becomes setting voltage within the latch timer preset time, counter is initialized. If the slew
rate of the power supply is too slow and after the soft-start time, the output voltage does not reach the set output
voltage even if the latch timer preset time is over, the latch function may work unexpectedly.
*After the soft-start operation, fold back protection function is enabled for version B/D/F/H. The fold back function
will limit the oscillator frequency if the FB pin voltage becomes lower than typically 0.56V. For B/D version, the
oscillator frequency will be reduced typically into 170kHz, for F version, into 250kHz, for H version, into 400kHz.
If the slew rate of the power supply is too slow, and even after the soft-start time, the output voltage is still less
than 70% of the set output voltage, or FB pin voltage is less than typically 0.56V, then this function may work
unexpectedly.
The performance of power circuit using this IC largely depends on external components. Selection of external
components is very important, especially, do not exceed each rating value (voltage/current/power).
9
R1245x
Recommended values for each output voltage
R1245x00xA/B: 330kHz
0.8 to
1.2
1.2 to
2.5
2.5 to
5.0
VOUT (V)
5.0 ≤
R1(RUP) (kΩ)
R2(RBOT) (kΩ)
CSPD (pF)
=(VOUT / 0.8-1) × R2
16
12
1.20
1.20
open
470
2200
1000
COUT (μF)
47
47
10
22
15
22
33
L(μH)
4.7
R1245x00xC/D：500kHz
0.8 to
1.2
1.2 to
1.5
1.5 to
2.0
2.0 to
5.0
5.0 to
12.0
VOUT (V)
12.0 ≤
R1(RUP) (kΩ)
=(VOUT / 0.8-1) × R2
R2(RBOT) (kΩ)
CSPD (pF)
COUT (μF)
L(μH)
16
open
100
4.7
16
100
100
4.7
16
100
22
1.2
1000
22
1.2
1000
22
1.2
470
22
10
10
15
15
R1245x00xE/F：1000kHz
0.8 to
1.0
1.0 to
1.2
1.2 to
1.5
1.5 to
2.5
2.5 to
5.0
VOUT (V)
5.0 ≤
R1(RUP) (kΩ)
=(VOUT / 0.8-1) × R2
R2(RBOT) (kΩ)
CSPD (pF)
COUT (μF)
L(μH)
16
open
100
2.2
16
100
100
2.2
16
100
47
16
100
22
1.2
470
10
1.2
470
10
2.2
2.2
4.7
10
R1245x00xG/H：2400kHz
1.2 to
1.8
1.8 to
2.5
2.5 to
5.0
VOUT (V)
5.0 ≤
R1(RUP) (kΩ)
=(VOUT / 0.8-1) × R2
R2(RBOT) (kΩ)
CSPD (pF)
COUT (μF)
L(μH)
16
100
10
12
100
10
1.2
470
4.7
2.2
1.2
470
4.7
4.7
1.0
1.5
10
R1245x
*Divider resisters values and possible setting range of input /output
Input Voltage range [V]
VOUT
R1(RUP)
R2(RBOT)
[V]
[kΩ]
[kΩ]
Ver.AB
Ver.CD
Ver.EF
4.5 to 7
Ver.GH
-
0
0
open
16
4.5 to
13.5
0.8
4.5 to 20
4.5 to
25.5
4.5 to 17
4.5 to 20
4.5 to 8.5
4.5 to 10
-
-
1
4
8
16
16
12
12
16
16
12
16
1.2
16
12
1.2
1.2
4.5 to 30
4.5 to 30
4.5 to 30
4.5 to 30
6
4.5 to
12.5
4.5 to
5.5
10.5
14
1.5
1.8
2
4.5 to 25
4.5 to 30
4.5 to 30
20
4.5 to
6.5
4.5 to 15
4.5 to 17
15
24
4.5 to 7
1.8
34
2.5
4.5 to 30
4.5 to 30
4.5 to 30
4.5 to 30
4.5 to 21
4.5 to 9
25.5
2.55
4.5 to
27.5
4.5 to
12
3.3
5
3.75
6.3
1.2
1.2
1.2
1.2
1.2
1.2
1.2
5.5 to 30
6.5 to 30
10 to 30
13 to 30
5.5 to 30
6.5 to 30
10 to 30
13 to 30
6 to 30
7 to 30
7 to 17
8 to 20
6
7.8
11 to 30
14 to 30
17 to 30
12 to 30
16 to 30
20 to 30
30
9
12.3
16.8
12
15
24
16.5 to 30 16.5 to 30
21.3
34.8
26.5 to 30 26.5 to 30 27.5 to 30
11
R1245x
Recommended external Components examples (Considering all the range)
Characteristics
Value
Parts Name
MFR
Symbol
TAIYO YUDEN
MURATA
CIN
50V/X5R
50V/X7R
10μF
4.7μF
2.2μF
10μF
UMK325BJ106MM-T
GRM31CR71H475KA12L
GRM31CR71H225KA88L
UMK325BJ106MM-T
MURATA
50V/X7R
50V/X5R
TAIYO YUDEN
COUT
50V/X7R
25V/X7R
10V/X7R
Nippon Chemi-Con
MURATA
10μF
10μF
KTS500B106M55N0T00
GRM31CR71E106K
GRM31CR71A226M
MURATA
22μF
GRM32EB31C476KE15
GRM32ER71A476KE15
MURATA
MURATA
16V B
10V/X7R
47μF
47μF
NOTE: The value of COUT depends on the setting
output voltage.
TAIYO YUDEN
TDK
CBST
16V/X7R
1.8A
0.47μF
10μH
EMK212B7474KD-T
SLF6045T-100M1R6-3PF
SLF7045T-4R7M2R0-PF
NR4018T-4R7M2R0-PF
NR6020T4R7M
L
1.65A
1.7A
TDK
4.7μH
4.7μH
4.7μH
10μH
15μH
22μH
33μH
2.2μH
2.2μH
1.5μH
TDK
2.4A
TAIYO YUDEN
TAIYO YUDEN
TAIYO YUDEN
TAIYO YUDEN
TAIYO YUDEN
TDK
1.9A
NR6028T100M
2.3A
NR6045T150M
1.9A
NR6045T220M
1.9A
NR8040T330M
1.7A
VLCF4020T-2R2N1R7
NR4012T2R2M
1.65A
1.8A
TAIYO YUDEN
TAIYO YUDEN
TAIYO YUDEN
Panasonic
TOSHIBA
NR3015T1R5N
1.8A
1.0μH
0.42V
0.37V
0.55V
NR4010T1R0N
30V/1.5A
30V/2.0A
40V/2.0A
40V/2.0A
D
MA22D28
CMS06
TOSHIBA
CMS11
0.43V
0.32V
MA24D60
Panasonic
15V/2.0A
SBS010M
SANYO
RCE
An UP DIODE is formed between the CE pin and the VIN pin as an ESD protection element.
If the CE pin may become higher than the voltage of the VIN pin, connect the 10kohm resistance between the
CE pin and VIN pin, to prevent a large current from flowing into the VIN pin from the CE pin.
12
R1245x
Operation of the Buck Converter and the Output Current
The DC/DC converter charges energy in the inductor when the switch turns on, and discharges the energy from
the inductor when the switch turns off and controls with less energy loss, so that a lower output voltage than the
input voltage is obtained. Refer to the following figures.
<Basic Circuit>
<Current through the inductor>
IL
ILmax
i1
VOUT
ILmin
topen
L
Switch
Diode
VIN
i2
COUT
GND
ton
toff
T=1/fosc
Step 1: The switch turns on and current IL (=i1) flows, and energy is charged into COUT. At this moment, IL
increases from ILmin (=0) to reach ILmax in proportion to the on-time period (ton) of the switch.
Step 2: When the switch turns off, the diode turns on in order to maintain IL at ILmax, and current IL (=i2)
flows.
Step 3: IL (=i2) decreases gradually and reaches IL=ILmin=0 after a time period of topen, and the diode
turns off. This case is called as discontinuous mode. If the output current becomes large, next switching
cycle starts before IL becomes 0 and the diode turns off. In this case, IL value increases from ILmin (>0),
and this case is called continuous mode.
In the case of PWM control system, the output voltage is maintained by controlling the on-time period (ton), with
the oscillator frequency (fosc) being maintained constant.
Output Current and Selection of External Components
The relation between the output current and external components is as follows:
When the switch of LX turns on:
(Wherein, the peak to peak value of the ripple current is described as IRP, the ON resistance of the switch is
described as RONH, and the diode forward voltage as VF, and the DC resistance of the inductor is described as
RL, and on time of the switch is described as ton)
VIN = VOUT + (RONH + RL) × IOUT + L × IRP / ton ································································ Equation 1
When the switch turns off (the diode turns on) as toff:
L × IRP / toff = VF + VOUT + RL × IOUT ··············································································· Equation 2
Put Equation 2 to Equation 1 and solve for ON duty of the switch, ton / ( toff + ton) = DON,
DON = (VOUT + VF + RL × IOUT)/(VIN + VF - RONH × IOUT)···················································· Equation 3
13
R1245x
Ripple Current is as follows:
IRP = (VIN − VOUT − RONH × IOUT − RL × IOUT) × DON / fosc / L·············································Equation 4
wherein, peak current that flows through L, and the peak current ILmax is as follows:
ILmax = IOUT + IRP / 2······································································································Equation 5
As for the valley current ILmin,
ILmin = IOUT - IRP / 2 ·······································································································Equation 6
If ILmin<0, the step-down DC/DC converter operation becomes current discontinuous mode.
Therefore the current condition of the current discontinuous mode, the next formula is true.
IOUT < IRP / 2 ··················································································································Equation 7
Consider ILmax and ILmin, conditions of input and output and select external components.
*The above explanation is based on the calculation in an ideal case in continuous mode.
14
R1245x
Ripple Current and Lx current limit
The ripple current of the inductor may change according to the various reasons. In the R1245x series, as an
Lx current limit, Lx peak current limit is used. Therefore the upper limit of the inductor current is fixed.
The peak current limit is not the average current of the inductor (output current). If the ripple current is large,
peak current becomes also large. The characteristic is used for the fold back current limit of version B/D/F/H.
In other words, the peak current limit is maintained and the switching frequency is reduced, as a result, the
average current of the inductor is reduced. To release this condition, at 170kHz for version B/D, at 250kHz
for version F, at 400kHz for version H must not be beyond the peak current limit. In the fig.1, the sequence of
the Lx current limit function is described.
Fig.1 LX Limit function sequence
Latch protection function for version A/C/E/G
The latch function works after detecting current limit and if the output voltage becomes low for a certain time,
the output is latched off. Refer to the TECHNICAL NOTES.
Fold back protection function for version B/D/F/H
If FB voltage becomes lower than approximately 0.56V, the fold back protection function limits the oscillator
frequency to typically 170kHz for version B/D, typically 250kHz fir version F, typically 400kHz for version H.
By reducing frequency, the ripple current increases. The R1245x has the peak current limit function,
therefore as in the equation 8, the Lx average current decreases by the increase of the ripple current.
IOUT =ILmax + IRP / 2
Equation 8
If FB voltage becomes less than 0.56V, the oscillator frequency is reduced. At heavy load, if the R1245x
becomes into the fold back protection mode, the situation may not be released by increase the ripple current.
In terms of other notes on this protection function, refer to the TECHNICAL NOTES.
15
R1245x
MAXIMUM OUTPUT CURRENT
The output current of the R1245x is limit by the power dissipation PD of the package and the maximum
specification 1.2A. The loss of the IC includes the switching loss, and it is difficult to estimate. To estimate the
maximum output, using the efficiency data is one method.
By using the efficiency data, the loss including the external components can be calculated with the equation,
(100/efficiency(%)-1)x(VOUT(V)xIOUT(V)). From this equation, by reducing the loss of external components, the
loss of the IC can be estimated. The main loss of the external components is composed by the rectifier diode
and DCR of the inductor. Supposed that the forward voltage of the diode is described as VF, the loss of the
diode can be described as follows:
(VIN(V)-RON(Ω)xIOUT(A)-VOUT(V)-VF(V)))/VIN(V)xVF(V)xIOUT(A)
The loss by the DCR of the inductor can be calculated by the formula DCR(Ω)xIOUT2(A).
Thus,
The loss of the IC = (100 / efficiency(%) -1) x (VOUT(V) x IOUT(A) - (VIN(V) - RON(Ω) x IOUT(A) - VOUT(V) -VF(V)) /
VIN(V) x VF(V) xIOUT(A) - DCR(Ω) x IOUT2(A)
The efficiency of the R1245 at Ta=25°C, VIN=12V, VOUT=3.3V, IOUT=600mA is approximately 89.5% for version
A/B(Oscillator frequency 330kHz). Supposed that the On resistance of the internal driver is 0.35Ω, the DCR of
the inductor is 65mΩ, the VF of the rectifier diode is 0.3V and applied to the formula above,
The loss of the IC = (100% / 89.5% - 1) x (3.3V x 0.6A) - (12V - 0.35Ω x 0.6A - 3.3V - 0.3V) / 12V x 0.3V x 0.6A
- 0.065Ωx0.62A=86mW
The power dissipation PD of the package is specified at Ta=25°C based on the Tjmax=125°C. Thus the thermal
resistance of the package θja=(Tjmax(°C)-Ta(°C))/PD(W), therefore the thermal resistance of the each
available package is as follows:
HSOP-8E: (125°C-25°C)/2.9W=34.5°C/W
DFN(PLP)2020-8: (125°C-25°C)/0.88W=114°C/W
SOT-23-6W: (125°C-25°C)/0.43W=233°C/W
Due to the loss of the IC is 86mW for this example, therefore Tj increase of the each package is as follows:
HSOP-8E: 34.5°C/Wx86mW=2.96°C
DFN(PLP)2020-8: 114°C/Wx86mW=9.80°C
SOT-23-6W: 233°C/Wx86mW=20.0°C
For all the packages, even if the ambient temperature is at 105°C, Tj can be suppressed less than 125°C. By
the increase of the temperature, on resistance and switching loss increases, therefore, temperature margin is
not enough, measure the efficiency at the actual maximum temperature and recalculation is necessary.
At the same condition, if the preset frequency is 2400kHz, the efficiency will be down to approximately 81%.
The result of the loss calculation is 310mW, therefore the Tj increase of each package is,
HSOP-8E: 34.5°C/Wx310mW=11°C
DFN(PLP)2020-8: 114°C/Wx310mW=35°C
SOT-23-6W: 233°C/Wx310mW=72°C
HSOP-8E can be used at the ambient temperature 105°C, DFN(PLP)2020-8 can be used at the ambient
temperature up to 90°C, SOT-23-6W can be used at the ambient temperature up to 53°C. Note that the result
is different by the frequency.
16
R1245x
The next graphs are the output current and estimated ambient temperature limit.
Maximum output current
VIN=12V , VOUT=3.3V , fosc=330kHz
-40°C
105°C
1400
1200
1000
800
600
400
200
0
SOT-23-6W
DFN2020-8
HSOP-8E
-50
0
50
100
150
Ta[°C]
VIN=12V , VOUT=3.3V , fosc=2400kHz
-40°C
1400
105°C
1200
1000
800
600
400
200
0
SOT-23-6W
DFN2020-8
HSOP-8E
-50
0
50
100
150
Ta[°C]
17
R1245x
INTERNAL EQUIVALENT CIRCUIT FOR EACH PIN
<BST pin>
<Lx pin>
Regulator
VIN
BST
LX
LX
<FB pin>
<CE pin>
Regulator
VIN
CE
FB
<TEST pin>
Regulator
TEST
18
R1245x
TYPICAL CHARACTERISTICS
1) FB voltage vs. Temperature
2)Driver On resistance vs. Temperature
R1245x00xx
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
R1245x00xx
(VIN=12V)
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
(VIN=12V)
500
450
400
350
300
250
200
0.808
0.806
0.804
0.802
0.8
0.798
0.796
0.794
0.792
-50 -25
0
25 50 75 100 125
Ta (
-50 -25
0
25 50 75 100 125
Ta (
)
)
℃
℃
3) Oscillator frequency vs. Temperature
R1245x00xA/R1245x00xB
R1245x00xC/R1245x00xD
(VIN=12V)
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
(VIN=12V)
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
550
360
350
340
330
320
310
300
525
500
475
450
-50 -25
0
25 50 75 100 125
Ta (
-50 -25
0
25 50 75 100 125
Ta (
)
)
℃
℃
R1245x00xE/R1245x00xF
(VIN=12V)
R1245x00xG/R1245x00xH
(VIN=12V)
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
2640
2560
2480
2400
2320
2240
2160
1100
1050
1000
950
900
-50 -25
0
25 50 75 100 125
Ta (
-50 -25
0
25 50 75 100 125
Ta (
)
)
℃
℃
19
R1245x
4) Maximum duty cycle vs. Temperature
R1245x00xA/R1245x00xB
R1245x00xC/R1245x00xD
(VIN=12V)
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
(VIN=12V)
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
99
98
97
96
95
94
93
92
99
98
97
96
95
94
93
92
-50 -25
0
25 50 75 100 125
Ta (
-50 -25
0
25 50 75 100 125
Ta (
)
)
℃
℃
R1245x00xE/R1245x00xF
(VIN=12V)
R1245x00xG/R1245x00xH
(VIN=12V)
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
96
95
94
93
92
91
90
89
86
85
84
83
82
81
80
79
-50 -25
0
25 50 75 100 125
Ta (
-50 -25
0
25 50 75 100 125
Ta (
)
)
℃
℃
20
R1245x
5) Fold back frequency vs. Temperature
R1245x00xB
R1245x00xD
(VIN=12V)
(VIN=12V)
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
240
220
200
180
160
140
120
100
80
240
220
200
180
160
140
120
100
80
-50 -25
0
25 50 75 100 125
Ta (
-50 -25
0
25 50 75 100 125
Ta (
)
)
℃
℃
R1245x00xF
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
R1245x00xH
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
(VIN=12V)
(VIN=12V)
420
370
320
270
220
170
120
720
620
520
420
320
220
120
-50 -25
0
25 50 75 100 125
Ta (
-50 -25
0
25 50 75 100 125
Ta (
)
)
℃
℃
6) High side switch current limit vs. Temperature
R1245x00xx
(VIN=12V)
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
2.7
2.5
2.3
2.1
1.9
1.7
1.5
-50 -25
0
25 50 75 100 125
Ta (
)
℃
21
R1245x
7) UVLO detector threshold vs. Temperature
8) UVLO released voltage vs. Temperature
R1245x00xx
R1245x00xx
4.1
4
4.2
4.1
4
3.9
3.8
3.7
3.6
3.9
3.8
-50 -25
0
25 50 75 100 125
Ta (
-50 -25
0
25 50 75 100 125
Ta (
)
)
℃
℃
9) Soft-start time vs. Temperature
10) Timer latch delay vs. Temperature
R1245x00xx
R1245x00xx
(VIN=12V)
(VIN=6V)
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
1.8
1.6
1.4
1.2
1
6
5
4
3
2
1
0.8
0.6
0.4
-50 -25
0
25 50 75 100 125
Ta (
-50 -25
0
25 50 75 100 125
Ta (
)
℃
)
℃
11) CE “H” Input voltage vs. Temperature
12) CE “L” Input voltage vs. Temperature
R1245x00xx
R1245x00xx
(VIN=12V)
(VIN=12V)
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
2.5
2
2.5
2
1.5
1
1.5
1
0.5
0.5
-50 -25
0
25 50 75 100 125
Ta (
-50 -25
0
25 50 75 100 125
Ta (
)
)
℃
℃
22
R1245x
13) Soft-start waveform
R1245x00xA/R1245x00xB
VOUT=3.3V , VIN=12V , IOUT=0mA , Ta=25°C
R1245x00xA/R1245x00xB
VOUT=3.3V , VIN=12V , IOUT=600mA , Ta=25°C
V
CE
V
CE
(5V/div)
(5V/div)
V
OUT
V
OUT
(1V/div)
(1V/div)
I
LX
I
LX
(200mA/div)
(200mA/div)
LX
V
LX
V
(10V/div)
(10V/div)
200µs/div
200µs/div
14) Switching operation waveform
R1245x00xA/R1245x00xB
R1245x00xA/R1245x00xB
VOUT=3.3V , VIN=12V , IOUT=0mA , Ta=25°C
VOUT=3.3V , VIN=12V , IOUT=600mA , Ta=25°C
OUT (AC)
OUT
V
V
(AC)
(20mV/div)
(20mV/div)
LX
I
ILX
(200mA/div)
(200mA/div)
LX
LX
V
V
(5V/div)
(5V/div)
2µs/div
2µs/div
R1245x00xG/R1245x00xH
R1245x00xG/R1245x00xH
VOUT=3.3V , VIN=12V , IOUT=20mA , Ta=25°C
VOUT=3.3V , VIN=12V , IOUT=600mA , Ta=25°C
V
OUT (AC)
VOUT (AC)
(20mV/div)
(20mV/div)
I
LX
I
LX
(200mA/div)
(200mA/div)
V
LX
VLX
(5V/div)
(5V/div)
200ns/div
200ns/div
23
R1245x
15) Loaf transient response waveform
R1245x00xA/R1245x00xB
R1245x00XA/R1245x00xB
VOUT=0.8V , VIN=12V , IOUT=600⇔1200mA , Ta=25°C
VOUT=3.3V , VIN=12V , IOUT=600⇔1200mA , Ta=25°C
VOUT
VOUT
(100mV/div)
(200mV/div)
IOUT
IOUT
(500mA/div)
(500mA/div)
100µs/div
100µs/div
R1245x00xG/R1245x00xH
R1245x00xG/R1245x00xH
VOUT=1.5V , VIN=4.5V , IOUT=600⇔1200mA , Ta=25°C
VOUT=3.3V , VIN=12V , IOUT=600⇔1200mA , Ta=25°C
V
OUT
V
OUT
( 100mV /div )
( 100mV /div )
I
OUT
I
OUT
( 500mA /div )
( 500mA /div )
50us/div
50us/div
24
R1245x
16) Limit latch operation waveform
R1245x00xA
17) Released waveform from limit latch
R1245x00xA
VOUT=3.3V , VIN=12V , ROUT=5.5Ω→0.05Ω, Ta=25°C
VOUT=3.3V , VIN=12V , ROUT=5.5Ω→0.05Ω→5.5Ω
, Ta=25°C
V
OUT
VOUT
(2V/div)
(2V/div)
V
LX
VLX
(10V/div)
(10V/div)
I
LX
I
LX
(1A/div)
(1A/div)
1ms/div
1ms/div
18) Fold back operation waveform
R1245x00xB
19) Released waveform from fold back
R1245x00xB
VOUT=3.3V , VIN=12V , ROUT=5.5Ω→0.05Ω
Ta=25°C
VOUT=3.3V , VIN=12V , ROUT=5.5Ω→0.05Ω→5.5Ω
Ta=25°C
V
OUT
V
OUT
(2V/div)
(2V/div)
LX
LX
V
V
(10V/div)
(10V/div)
LX
I
LX
I
(1A/div)
(1A/div)
20µs/div
20µs/div
20) Switching waveform at fold back operation
R1245x00xB
VOUT=3.3V , VIN=12V , ROUT=0.05Ω, Ta=25°C
OUT
V
(2V/div)
V
LX
(10V/div)
I
LX
(1A/div)
2µs/div
25
R1245x
21) Output current vs. Efficiency (Version A/B)
R1245x00xA/R1245x00xB
R1245x00xA/R1245x00xB
OUT=3.3V
(Ta=25 )
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ ℃
V
OUT=0.8V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
V
(Ta=25
)
℃
100
80
60
40
20
0
100
80
60
40
20
0
VIN = 4.5V
VIN = 6.0V
VIN = 18V
VIN = 4.5 V
VIN = 12 V
VIN = 24 V
0.01
0.1
1
10
100 1000 10000
0.01
0.1
1
10
100 1000 10000
IOUT (mA)
IOUT (mA)
R1245x00xA/R1245x00xB
OUT=5.0V
R1245x00xA/R1245x00xB
OUT=12V
V
V
(Ta=25
)
(Ta=25 )
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ ℃
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
℃
100
80
60
40
20
0
100
80
60
40
20
0
VIN = 12V
VIN = 24V
VIN = 30V
VIN = 18V
VIN = 24V
VIN = 30V
0.01
0.1
1
10
100 1000 10000
0.01
0.1
1
10
100 1000 10000
IOUT (mA)
IOUT (mA)
R1245x00xA/R1245x00xB
OUT=15V
R1245x00xA/R1245x00xB
OUT=24V
V
V
(Ta=25
)
(Ta=25 )
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ ℃
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
℃
100
80
60
40
20
0
100
80
60
40
20
0
VIN = 24V
VIN = 30V
VIN=30V
0.01
0.1
1
10
100 1000 10000
0.01
0.1
1
10
100 1000 10000
IOUT (mA)
IOUT (mA)
26
R1245x
22) Output Current vs. Efficiency (Version C/D)
R1245x00xC/R1245x00xD
VOUT=0.8V
R1245x00xC/R1245x00xD
OUT=3.3V
V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
(Ta=25
)
℃
(Ta=25
)
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
℃
100
80
60
40
20
0
100
80
60
40
20
0
VIN = 4.5V
VIN = 12V
VIN = 24V
VIN = 4.5V
VIN = 6.0V
VIN = 12V
0.01
0.1
1
10
100 1000 10000
0.01
0.1
1
10
100 1000 10000
IOUT (mA)
IOUT (mA)
R1245x00xC/R1245x00xD
OUT=5.0V
R1245x00xC/R1245x00xD
OUT=12V
V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
(Ta=25
)
℃
(Ta=25
)
℃
100
100
80
60
40
20
0
VIN = 12V
VIN = 24V
VIN = 30V
VIN = 18V
VIN = 24V
VIN = 30V
80
60
40
20
0
0.01
0.1
1
10
100 1000 10000
0.01
0.1
1
10
100 1000 10000
IOUT (mA)
IOUT (mA)
R1245x00xC/R1245x00xD
OUT=15V
R1245x00xC/R1245x00xD
OUT=24V
(Ta=25 )
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ ℃
V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
V
(Ta=25
)
℃
100
80
60
40
20
0
100
80
60
40
20
0
VIN = 24V
VIN = 30V
VIN = 30V
0.01
0.1
1
10
100 1000 10000
0.01
0.1
1
10
100 1000 10000
IOUT (mA)
IOUT (mA)
27
R1245x
23) Output current vs. Efficiency (Version E/F)
R1245x00xE/R1245x00xF
R1245x00xE/R1245x00xF
VOUT=3.3V
(Ta=25 )
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ ℃
V
OUT=0.8V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
(Ta=25
)
℃
100
80
60
40
20
0
100
80
60
40
20
0
VIN = 4.5V
VIN = 12V
VIN = 24V
VIN = 4.5V
VIN = 6.0V
0.01
0.1
1
10
100 1000 10000
0.01
0.1
1
10
100 1000 10000
IOUT (mA)
IOUT (mA)
R1245x00xE/R1245x00xF
VOUT=5.0V
R1245x00xE/R1245x00xF
VOUT=12V
(Ta=25
)
(Ta=25
)
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
℃
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
℃
100
80
60
40
20
0
100
80
60
40
20
0
VIN = 12V
VIN = 24V
VIN = 30V
VIN = 24V
VIN = 30V
0.01
0.1
1
10
100 1000 10000
0.01
0.1
1
10
100 1000 10000
IOUT (mA)
IOUT (mA)
R1245x00xE/R1245x00xF
VOUT=15V
R1245x00xE/R1245x00xF
VOUT=24V
(Ta=25
)
(Ta=25 )
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ ℃
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
℃
100
80
60
40
20
0
100
80
60
40
20
0
VIN = 24V
VIN = 30V
VIN = 30V
0.01
0.1
1
10
100 1000 10000
0.01
0.1
1
10
100 1000 10000
IOUT (mA)
IOUT (mA)
28
R1245x
24) Output current vs. Efficiency (Version G/H)
R1245x00xG/R1245x00xH
OUT=3.3V
R1245x00xG/R1245x00xH
VOUT=1.5V
V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
(Ta=25
)
℃
(Ta=25
)
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
℃
100
80
60
40
20
0
100
80
60
40
20
0
VIN = 6V
VIN = 10V
VIN = 12V
VIN = 4.5V
0.01
0.1
1
10
100 1000 10000
0.01
0.1
1
10
100 1000 10000
IOUT (mA)
IOUT (mA)
R1245x00xG/R1245x00xH
VOUT=5.0V
R1245x00xG/R1245x00xH
VOUT=12V
(Ta=25
)
(Ta=25 )
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ ℃
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
VIN = 8.0V
℃
100
80
60
40
20
0
100
80
60
40
20
0
VIN = 24V
VIN = 12V
VIN = 30V
0.01
0.1
1
10
100 1000 10000
0.01
0.1
1
10
100 1000 10000
IOUT (mA)
IOUT (mA)
29
R1245x
25) Output current vs Output voltage (Version A/B)
R1245x00xA/R1245x00xB
OUT=3.3V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
R1245x00xA/R1245x00xB
V
VOUT=0.8V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
(Ta=25
)
(Ta=25
)
℃
℃
ꢀꢀꢀ
0.808
3.33
3.32
3.31
3.30
3.29
3.28
3.27
3.26
3.25
VIN=4.5V
VIN=18V
VIN=6.0V
VIN = 4.5 V
VIN = 24 V
VIN = 12 V
0.806
0.804
0.802
0.800
0.798
0.796
0.794
0.792
0
200
400
600
800 1000 1200
0
200 400 600 800 1000 1200
IOUT (mA)
IOUT (mA)
R1245x00xA/R1245x00xB
R1245x00xA/R1245x00xB
VOUT=12V
(Ta=25 )
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ ℃
V
OUT=5.0V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
(Ta=25
)
℃
5.05
5.03
5.01
4.99
4.97
4.95
12.30
12.20
12.10
12.00
11.90
VIN = 12V
VIN = 30V
VIN = 24V
VIN = 18V
VIN = 30V
VIN = 24V
0
200 400 600 800 1000 1200
IOUT (mA)
0
200
400
600
800 1000 1200
IOUT (mA)
R1245x00xA/R1245x00xB
R1245x00xA/R1245x00xB
VOUT=24V
V
OUT=15V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
(Ta=25
)
(Ta=25 )
℃
℃
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
15.60
15.40
15.20
15.00
14.80
24.70
24.50
24.30
24.10
23.90
VIN = 24V
VIN = 30V
VIN = 30V
0
200 400 600 800 1000 1200
IOUT (mA)
0
200
400
600
800 1000 1200
IOUT (mA)
30
R1245x
26) Output current vs. Output voltage (Version C/D)
R1245x00xC/R1245x00xD
R1245x00xC/R1245x00xD
V
OUT=0.8V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
VOUT=3.3V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
(Ta=25 )
℃
(Ta=25
)
℃
0.808
0.806
0.804
0.802
0.800
0.798
0.796
0.794
0.792
3.33
3.32
3.31
3.30
3.29
3.28
3.27
3.26
3.25
VIN = 4.5V
VIN = 12V
VIN = 6.0V
VIN = 4.5V
VIN = 24V
VIN = 12V
0
200 400 600 800 1000 1200
IOUT (mA)
0
200
400
600
800 1000 1200
IOUT (mA)
R1245x00xC/R1245x00xD
VOUT=5.0V
R1245x00xC/R1245x00xD
VOUT=12V
(Ta=25
)
(Ta=25 )
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ ℃
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
℃
5.05
5.03
5.01
4.99
4.97
4.95
12.20
12.10
12.00
11.90
11.80
VIN = 12V
VIN = 30V
VIN = 24V
VIN = 18V
VIN = 30V
VIN = 24V
0
200 400 600 800 1000 1200
IOUT (mA)
0
200
400
600
800 1000 1200
IOUT (mA)
R1245x00xC/R1245x00xD
VOUT=15V
R1245x00xC/R1245x00xD
VOUT=24V
(Ta=25
)
℃
(Ta=25 )
℃
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
15.40
15.20
15.00
14.80
14.60
24.40
24.20
24.00
23.80
23.60
VIN = 24V
VIN = 30V
VIN = 30V
0
200 400 600 800 1000 1200
IOUT (mA)
0
200
400
600
800 1000 1200
IOUT (mA)
31
R1245x
27) Output current vs. Output voltage (Version E/F)
R1245x00xE/R1245x00xF
VOUT=3.3V
R1245x00xE/R1245x00xF
VOUT=0.8V
(Ta=25
)
℃
(Ta=25 )
℃
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
ꢀꢀꢀ
0.808
3.33
3.32
3.31
3.30
3.29
3.28
3.27
3.26
3.25
VIN = 4.5V
VIN = 24V
VIN = 12V
0.806
0.804
0.802
0.800
0.798
0.796
0.794
0.792
VIN = 4.5V
0
200
400
600
800 1000 1200
0
200 400 600 800 1000 1200
IOUT (mA)
IOUT (mA)
R1245x00xE/R1245x00xF
VOUT=5.0V
R1245x00xE/R1245x00xF
VOUT=12V
(Ta=25
)
(Ta=25 )
℃
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
℃
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
5.05
5.03
5.01
4.99
4.97
4.95
12.20
12.10
12.00
11.90
11.80
VIN = 12V
VIN = 30V
VIN = 24V
VIN = 24V VIN = 30V
0
200 400 600 800 1000 1200
IOUT (mA)
0
200
400
600
800 1000 1200
IOUT (mA)
R1245x00xE/R1245x00xF
VOUT=15V
R1245x00xE/R1245x00xF
VOUT=24V
(Ta=25
)
℃
(Ta=25 )
℃
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
15.60
15.40
15.20
15.00
14.80
24.40
24.20
24.00
23.80
23.60
VIN = 24V
VIN = 30V
VIN = 30V
0
200 400 600 800 1000 1200
IOUT (mA)
0
200
400
600
800 1000 1200
IOUT (mA)
32
R1245x
28) Output current vs. Output voltage (Version G/H)
R1245x00xG/R1245x00xH
R1245x00xG/R1245x00xH
V
OUT=1.5V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
VIN = 4.5V
VOUT=3.3V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
(Ta=25 )
℃
(Ta=25
)
℃
1.515
1.510
1.505
1.500
1.495
1.490
1.485
3.33
3.32
3.31
3.30
3.29
3.28
3.27
3.26
3.25
VIN = 6V
VIN = 10V
VIN = 12V
0
200
400
600
800 1000 1200
0
200
400
600
800 1000 1200
IOUT (mA)
IOUT (mA)
R1245x00xG/R1245x00xH
OUT=5.0V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
R1245x00xG/R1245x00xH
VOUT=12V
V
(Ta=25 )
℃
(Ta=25
)
℃
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
5.05
5.03
5.01
4.99
4.97
4.95
12.20
12.10
12.00
11.90
11.80
VIN = 8.0V VIN = 12V
VIN = 24V VIN = 30V
0
200
400
600
800 1000 1200
0
200
400
600
800 1000 1200
IOUT (mA)
IOUT (mA)
33
R1245x
29) Input voltage vs. Output voltage (Version A/B)
R1245x00xA/R1245x00xB
R1245x00xA/R1245x00xB
OUT=3.3V
(Ta=25 )
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ ℃
V
OUT=0.8V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
V
(Ta=25
)
℃
0.808
0.806
0.804
0.802
0.800
0.798
0.796
0.794
0.792
3.33
3.32
3.31
3.30
3.29
3.28
3.27
IOUT=1mA
IOUT=10mA
IOUT=1200mA
IOUT=1mA
IOUT=100mA
IOUT=1200mA
IOUT=100mA
IOUT=500mA
4
6
8
10
(V)
12
14
16
18
4
8
12
16
(V)
20
24
28
V
IN
V
IN
R1245x00xA/R1245x00xB
VOUT=5.0V
R1245x00xA/R1245x00xB
VOUT=12V
(Ta=25
)
(Ta=25 )
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ ℃
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
℃
5.05
5.03
5.01
4.99
4.97
4.95
12.20
12.15
12.10
12.05
12.00
11.95
IOUT=1mA
IOUT=100mA
IOUT=1200mA
IOUT=100mA
IOUT=1200mA
IOUT=500mA
IOUT=500mA
4
6
8 10 12 14 16 18 20 22 24 26 28 30
(V)
12 14 16 18 20 22 24 26 28 30
(V)
V
IN
V
IN
R1245x00xA/R1245x00xB
OUT=15V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
R1245x00xA/R1245x00xB
OUT=24V
(Ta=25 )
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ ℃
V
V
(Ta=25
)
℃
15.30
15.20
15.10
15.00
14.90
24.20
24.10
24.00
23.90
23.80
IOUT=100mA
IOUT=1200mA
IOUT=500mA
IOUT=100mA
IOUT=1200mA
IOUT=500mA
14 16 18 20 22 24 26 28 30
(V)
24
25
26
27
(V)
28
29
30
V
IN
V
IN
34
R1245x
30) Input voltage vs. Output voltage (Version C/D)
R1245x00xC/R1245x00xD
R1245x00xC/R1245x00xD
V
OUT=0.8V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
VOUT=3.3V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
(Ta=25 )
℃
(Ta=25
)
℃
3.33
3.32
3.31
3.30
3.29
3.28
3.27
0.81
0.81
0.80
0.80
0.80
0.80
0.80
0.79
0.79
1mA
500mA
100mA
1200mA
1mA
500mA
100mA
1200mA
4.5
6
7.5
V
9
10.5
12
13.5
4
8
12
16
(V)
20
24
28
(V)
IN
V
IN
R1245x00xC/R1245x00xD
OUT=5.0V
R1245x00xC/R1245x00xD
OUT=12V
(Ta=25 )
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ ℃
V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
V
(Ta=25
)
℃
5.05
5.03
5.01
4.99
4.97
4.95
12.20
12.10
12.00
11.90
11.80
1mA
100mA
100mA
500mA
500mA
1200mA
1200mA
4
6
8 10 12 14 16 18 20 22 24 26 28 30
(V)
12 14 16 18 20 22 24 26 28 30
(V)
V
IN
V
IN
R1245x00xC/R1245x00xD
OUT=15V
R1245x00xC/R1245x00xD
OUT=24V
V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
(Ta=25
)
℃
(Ta=25
)
℃
15.40
15.30
15.20
15.10
15.00
14.90
14.80
14.70
14.60
24.20
24.10
24.00
23.90
23.80
100mA
500mA
100mA
500mA
1200mA
1200mA
14 16 18 20 22 24 26 28 30
(V)
24
25
26
27
(V)
28
29
30
V
IN
V
IN
35
R1245x
31) Input voltage vs. Output voltage (Version E/F)
R1245x00xE/R1245x00xF
R1245x00xE/R1245x00xF
OUT=3.3V
V
OUT=0.8V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
(Ta=25
100mA
)
(Ta=25
)
℃
℃
0.808
0.806
0.804
0.802
0.800
0.798
0.796
0.794
0.792
3.33
3.32
3.31
3.30
3.29
3.28
3.27
1mA
1mA
100mA
500mA
1200mA
500mA
1200mA
4.5
5
5.5
(V)
6
6.5
4
8
12
16
(V)
20
24
28
V
IN
V
IN
R1245x00xE/R1245x00xF
OUT=5.0V
R1245x00xE/R1245x00xF
OUT=12V
V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
(Ta=25
)
(Ta=25
)
℃
℃
5.05
5.03
5.01
4.99
4.97
4.95
12.20
12.10
12.00
11.90
11.80
1mA
500mA
100mA
1200mA
100mA
1200mA
500mA
5
10
15
(V)
20
25
30
12 14 16 18 20 22 24 26 28 30
(V)
V
IN
V
IN
R1245x00xE/R1245x00xF
OUT=15V
R1245x00xE/R1245x00xF
OUT=24V
V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
(Ta=25
)
(Ta=25
℃
)
℃
15.40
15.20
15.00
14.80
14.60
24.40
24.20
24.00
23.80
23.60
100mA
1200mA
500mA
100mA
1200mA
500mA
16
18
20
22
(V)
24
26
28
30
26
27
28
(V)
29
30
V
IN
V
IN
36
R1245x
32) Input voltage vs. Output voltage (Version G/H)
R1245x00xG/R1245x00xH
R1245x00xG/R1245x00xH
OUT=3.3V
(Ta=25 )
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ ℃
V
OUT=1.5V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
V
(Ta=25
100mA
)
℃
1.515
1.510
1.505
1.500
1.495
1.490
1.485
3.33
3.32
3.31
3.30
3.29
3.28
3.27
1mA
500mA
1mA
100mA
1200mA
1200mA
500mA
4.5 5.5 6.5 7.5 8.5 9.5 10.5 11.5 12.5
(V)
4.5
4.7
4.9
(V)
5.1
5.3
5.5
V
V
IN
IN
R1245x00xG/R1245x00xH
OUT=5.0V
R1245x00xG/R1245x00xH
OUT=12V
(Ta=25 )
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ ℃
V
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀ
V
(Ta=25
)
℃
5.05
5.03
5.01
4.99
4.97
4.95
12.20
12.10
12.00
11.90
11.80
1mA
500mA
100mA
1200mA
100mA
1200mA
500mA
6
8
10
12
(V)
14
16
18
14 16 18 20 22 24 26 28 30
(V)
V
V
IN
IN
37
1.The products and the product specifications described in this document are subject to change or
discontinuation of production without notice for reasons such as improvement. Therefore, before
deciding to use the products, please refer to Ricoh sales representatives for the latest
information thereon.
2.The materials in this document may not be copied or otherwise reproduced in whole or in part
without prior written consent of Ricoh.
3.Please be sure to take any necessary formalities under relevant laws or regulations before
exporting or otherwise taking out of your country the products or the technical information
described herein.
4.The technical information described in this document shows typical characteristics of and
example application circuits for the products. The release of such information is not to be
construed as a warranty of or a grant of license under Ricoh's or any third party's intellectual
property rights or any other rights.
5.The products listed in this document are intended and designed for use as general electronic
components in standard applications (office equipment, telecommunication equipment,
measuring instruments, consumer electronic products, amusement equipment etc.). Those
customers intending to use a product in an application requiring extreme quality and reliability,
for example, in a highly specific application where the failure or misoperation of the product
could result in human injury or death (aircraft, spacevehicle, nuclear reactor control system,
traffic control system, automotive and transportation equipment, combustion equipment, safety
devices, life support system etc.) should first contact us.
6.We are making our continuous effort to improve the quality and reliability of our products, but
semiconductor products are likely to fail with certain probability. In order to prevent any injury to
persons or damages to property resulting from such failure, customers should be careful enough
to incorporate safety measures in their design, such as redundancy feature, firecontainment
feature and fail-safe feature. We do not assume any liability or responsibility for any loss or
damage arising from misuse or inappropriate use of the products.
7.Anti-radiation design is not implemented in the products described in this document.
8.Please contact Ricoh sales representatives should you have any questions or comments
concerning the products or the technical information.
For the conservation of the global environment, Ricoh is advancing the decrease of the negative environmental impact material.
After Apr. 1, 2006, we will ship out the lead free products only. Thus, all products that will be shipped from now on comply with RoHS Directive.
Basically after Apr. 1, 2012, we will ship out the Power Management ICs of the Halogen Free products only. (Ricoh Halogen Free products are
also Antimony Free.)
Halogen Free
RICOH COMPANY, LTD.
Electronic Devices Company
http://www.ricoh.com/LSI/
RICOH COMPANY, LTD.
Electronic Devices Company
● Higashi-Shinagawa Office (International Sales)
3-32-3, Higashi-Shinagawa, Shinagawa-ku, Tokyo 140-8655, Japan
Phone: +81-3-5479-2857 Fax: +81-3-5479-0502
RICOH EUROPE (NETHERLANDS) B.V.
● Semiconductor Support Centre
“Nieuw Kronenburg”Prof. W.H. Keesomlaan 1, 1183 DJ, Amstelveen, The Netherlands
P.O.Box 114, 1180 AC Amstelveen
Phone: +31-20-5474-309 Fax: +31-20-5474-791
RICOH ELECTRONIC DEVICES KOREA Co., Ltd.
11 floor, Haesung 1 building, 942, Daechidong, Gangnamgu, Seoul, Korea
Phone: +82-2-2135-5700 Fax: +82-2-2135-5705
RICOH ELECTRONIC DEVICES SHANGHAI Co., Ltd.
Room403, No.2 Building, 690#Bi Bo Road, Pu Dong New district, Shanghai 201203,
People's Republic of China
Phone: +86-21-5027-3200 Fax: +86-21-5027-3299
RICOH COMPANY, LTD.
Electronic Devices Company
● Taipei office
Room109, 10F-1, No.51, Hengyang Rd., Taipei City, Taiwan (R.O.C.)
Phone: +886-2-2313-1621/1622 Fax: +886-2-2313-1623
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