RP504x Series
600 mA PWM/VFM Step-Down DC/DC Converter with Synchronous Rectifier
NO.EA-259-150130
OUTLINE
The RP504x is a low supply current CMOS-based PWM/VFM step-down DC/DC converter with synchronous
rectifier featuring 600 mA*1 output current. Internally, a single converter consists of an oscillator, a reference
voltage unit, an error amplifier, a switching control circuit, a mode control circuit (RP504xxx1A/D), a soft-start
circuit, a Latch-type protection circuit, an under voltage lockout (UVLO) circuit a.nd switching transistors.
The RP504x is employing synchronous rectification for improving the efficiency of rectification by replacing
diodes with built-in switching transistors. Using synchronous rectification not only increases circuit performance
but also allows a design to reduce parts count.
Power controlling method can be selected from forced PWM control type or PWM/VFM auto switching control
type by inputting a signal to the MODE pin. In low output current, forced PWM control switches at fixed frequency
rate in order to reduce noise. Likewise, in low output current, PWM/VFM auto switching control automatically
switches from PWM mode to VFM mode in order to achieve high efficiency.
Output voltage is internally fixed type which allows output voltages that range from 0.8 V to 3.3 V in 0.1 V step.
The output voltage accuracy is as high as ±1.5% or ±18 mV.
Protection circuits included in the RP504x are overcurrent protection circuit and latch type protection circuit.
Overcurrent protection circuit supervises the inductor peak current in each switching cycle, and if the current
exceeds the LX current limit (ILXLIM), it turns off P-channel Tr. Latch type protection circuit latches the built-in driver
to the OFF state and stops the operation of the step-down DC/DC converter if the overcurrent status continues or
VOUT continues being the half of the setting voltage for equal or longer than protection delay time (tprot). To cancel
the latch type protection circuit, select the standby mode or the active mode with the CE pin, or drop the power
supply voltage below the UVLO detector threshold.
The RP504x is offered in 6-pin DFN(PLP)1216-6F, 6-pin DFN1616-6B and 5-pin SOT-23-5 packages which
achieve the smallest possible footprint solution on boards where area is limited.
*1
This is an approximate value. The output current is dependent on conditions and external components.
1
RP504x
NO.EA-259-150130
FEATURES
Supply Current ...................................................... Typ. 25 µA in VFM mode without any load
Standby Current .................................................... Max. 5 µA
Input Voltage Range ............................................. 2.3 V to 5.5 V (VOUT ≥ 1.0 V)
Output Voltage Range........................................... 0.8 V to 3.3 V in 0.1 V step
Output Voltage Accuracy....................................... ±1.5% (VOUT 1.2 V), ±18 mV (VOUT < 1.2 V)
Temperature-Drift Coefficient of Output Voltage ... Typ. ±40 ppm/°C
Oscillator Frequency ............................................. Typ. 2.25 MHz
Oscillator Maximum Duty Cycle ............................ Min. 100%
Built-in Driver ON Resistance ............................... Typ. Pch. 0.34 Ω, Nch. 0.43 Ω (VIN = 3.6 V)
UVLO Detector Threshold..................................... Typ. 2.0 V
Soft Start Time ...................................................... Typ. 0.15 ms
LX Current Limit ..................................................... Typ. 900 mA
Latch-type Protection Circuit ................................. Typ. 1.5 ms
Auto-discharge Function ....................................... Only for RP504xxxxD
Power Controlling Method ..................................... forced PWM control or PWM/VFM auto switching control
MODE Pin*1 ........................................................... “H”: forced PWM control,
“L”: PWM/VFM auto switching control
Package .............................................................. DFN1616-6B, DFN(PLP)1216-6F, SOT-23-5
*1
*1
DFN(PLP)1216-6F, DFN1616-6B: forced PWM control by pulling MODE pin “H” or PWM/VFM auto switching control by
pulling MODE pin “L”
SOT-23-5: forced PWM control for RP504xxxxC and PWM/VFM auto switching control for RP504xxxxB
APPLICATIONS
Power source for battery-powered equipment.
Power source for hand-held communication equipment, cameras, VCRs, camcorders.
Power source for HDD, portable equipment.
2
RP504x
NO.EA-259-150130
BLOCK DIAGRAMS
VIN
CE
CHIP
ENABLE
CURRENT
RAMP
COMPENSATION
FEEDBACK
OSCILLATOR
VREF
PWM
SOFT
START
CURRENT
PROTECTION
Lx
SWITCHING
CONTROL
UVLO
VOUT
MODE
GND
RP504xxxxA Block Diagram
VIN
CE
CHIP
ENABLE
CURRENT
FEEDBACK
RAMP
COMPENSATION
OSCILLATOR
VREF
SOFT
START
PWM
CURRENT
PROTECTION
Lx
SWITCHING
CONTROL
UVLO
VOUT
MODE
GND
RP504xxxxB Block Diagram
3
RP504x
NO.EA-259-150130
VIN
CE
CHIP
ENABLE
CURRENT
FEEDBACK
RAMP
COMPENSATION
OSCILLATOR
VREF
PWM
SOFT
START
CURRENT
PROTECTION
Lx
SWITCHING
CONTROL
UVLO
VOUT
MODE
GND
RP504xxxxC Block Diagram
VIN
CE
CHIP
ENABLE
RAMP
COMPENSATION
CURRENT
FEEDBACK
OSCILLATOR
VREF
SOFT
START
PWM
CURRENT
PROTECTION
LX
SWITCHING
CONTROL
UVLO
VOUT
MODE
GND
RP504xxxxD Block Diagram
4
RP504x
NO.EA-259-150130
SELECTION GUIDE
The set output voltage, the package type, the MODE control pin function and the auto-discharge*1 function
are user-selectable options.
Product Name
Package
Quantity per Reel
Pb Free
Halogen Free
RP504Kxx1$-E2
DFN(PLP)1216-6F
5,000 pcs
Yes
Yes
RP504Lxx1$-TR
DFN1616-6B
5,000 pcs
Yes
Yes
RP504Nxx1$-TR-FE
SOT-23-5
3,000 pcs
Yes
Yes
xx: Specify the set output voltage (VSET) within the range of 0.8 V(08) to 3.3 V(33) in 0.1 V steps.
Refer to the section of PACKAGE INFORMATION for detailed information.
$: Specify the package type, the MODE control pin function and the auto-discharge function.
$
A
B
C
D
*1
Package
MODE Control Pin Function
Auto-discharge
Function
MODE Pin
Power Controlling Method
Yes
“H”: forced PWM
“L”: PWM/VFM auto switching control
No
SOT-23-5
No
PWM/VFM auto switching control
No
SOT-23-5
No
forced PWM control
No
Yes
“H”: forced PWM control
“L”: PWM/VFM auto switching control
Yes
DFN1616-6B
DFN(PLP)1216-6F
DFN1616-6B
DFN(PLP)1216-6F
Auto-discharge function quickly lowers the output voltage to 0 V, when the chip enable signal is switched from the
active mode to the standby mode, by releasing the electrical charge accumulated in the external capacitor.
*2
0.05 V step is also available as a custom code.
5
RP504x
NO.EA-259-150130
PIN DESCRIPTION
6
5
4
6
5
4
5
4
1
2
3
DFN(PLP)1216-6F Pin Configurations
1
2
3
DFN1616-6B Pin Configurations
1
2
3
SOT-23-5 Pin Configurations
RP504Kxx1A, RP504Kxx1D: DFN(PLP)1216-6F Pin Description
Pin No.
Symbol
Description
1
VIN
Input Pin
Mode Control Pin
2
MODE
(“H”: forced PWM control, “L”: PWM/VFM auto switching
control)
3
CE
Chip Enable Pin (Active-high)
4
VOUT
Output Pin
5
GND
Ground Pin
6
LX
LX Switching Pin
RP504Lxx1A, RP504Lxx1D: DFN1616-6B Pin Description
Pin No.
Symbol
Description
1
CE
Chip Enable Pin (Active-high)
Mode Control Pin
2
MODE
(“H”: forced PWM control, “L”: PWM/VFM auto switching
control)
3
VIN
Input Pin
4
LX
LX Switching Pin
5
GND
Ground Pin
6
VOUT
Output Pin
The tab on the bottom of the package enhances thermal performance and is electrically connected to GND (substrate
level). It is recommended that the tab be connected to the ground plane on the board. If not, the tab can be left open.
RP504Nxx1B, RP504Nxx1C: SOT-23-5 Pin Description
Pin No.
Symbol
Description
1
VOUT
Output Pin
2
GND
Ground Pin
3
LX
LX Switching Pin
4
VIN
Input Pin
5
CE
Chip Enable Pin (Active-high)
6
RP504x
NO.EA-259-150130
ABSOLUTE MAXIMUM RATINGS
(GND = 0 V)
Absolute Maximum Ratings
Symbol
Item
Unit
−0.3 to 6.5
V
−0.3 to VIN +0.3
V
VIN
VIN Input Voltage
VLX
LX Pin Voltage
VCE
CE Pin Input Voltage
−0.3 to 6.5
V
VMODE
Mode Control Pin Voltage
−0.3 to 6.5
V
VOUT
VOUT Pin Voltage
−0.3 to 6.5
V
900
mA
ILX
LX Pin Output Current
PD
Power Dissipation
(Standard Land Pattern)*1
Ta
Tstg
*1
Rating
DFN(PLP)1216-6F
385
DFN1616-6B
640
SOT-23-5
420
mW
Operating Temperature Range
−40 to 85
°C
Storage Temperature Range
−55 to 125
°C
Refer to PACKAGE INFORMATION for detailed information.
ABSOLUTE MAXIMUM RATINGS
Electronic and mechanical stress momentarily exceeded absolute maximum ratings may cause the permanent
damages and may degrade the life time 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.
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.
7
RP504x
NO.EA-259-150130
ELECTRICAL CHARACTERISTICS
RP504xxx1A, RP504xxx1D Electrical Characteristics
Symbol
Item
Conditions
VIN
Operating Input Voltage
Max.
2.3
5.5
VOUT < 1.0
2.3
4.5
VOUT ≥ 1.2 V
x0.985
x1.015
VOUT < 1.2 V
−0.018
+0.018
VIN = VCE = 3.6 V
or VSET +1 V
Output Voltage Temperature
Coefficient
−40°C ≤ Ta ≤ 85°C
fosc
Oscillator Frequency
VIN = VCE = 3.6 V or VSET +1 V
IDD1
Supply Current 1
IDD2
Supply Current 2
VIN = VCE = VOUT
= 5.5 V
Istandby
Standby Current
VIN = 5.5 V, VCE = 0 V
ICEH
CE "H" Input Voltage
VIN = VCE = 5.5 V
ICEL
CE "L" Input Voltage
IMODEH
IMODEL
VOUT/Ta
Typ.
VOUT ≥ 1.0
Output Voltage
VOUT
(Ta = 25°C)
Min.
±40
V
V
ppm/°C
2.25
2.55
MHz
VIN = VCE = 5.5 V, VOUT = VSET
0.8
400
800
A
VMODE = 0 V
25
40
VMODE = 5.5 V
400
800
0
5
A
−1
0
1
A
VIN = 5.5 V, VCE = 0 V
−1
0
1
A
Mode "H" Input Current
VIN = VMODE = 5.5 V
−1
0
1
A
Mode "L" Input Current
VIN = 5.5 V, VMODE = 0 V
−1
0
1
A
VIN = VOUT = 5.5 V, VCE = 0 V
−1
0
1
A
*1
1.95
Unit
A
IVOUTH
VOUT "H" Input Current
IVOUTL
VOUT "L" Input Current
VIN = 5.5 V, VCE = VOUT = 0 V
−1
0
1
A
ILXLEAKH
LX Leakage Current "H"
VIN = VLX = 5.5 V, VCE = 0 V
−1
0
5
A
ILXLEAKL
LX Leakage Current "L"
VIN = 5.5 V, VCE = VLX = 0 V
−5
0
1
A
VCEH
CE "H" Input Voltage
VIN = 5.5 V
1.0
VCEL
CE "L" Input Voltage
VIN = 2.3 V
VMODEH
Mode ”H” Input Voltage
VIN = 5.5 V
VMODEL
Mode ”L” Input Voltage
VIN = 2.3 V
RLOW
Nch On Resistance*2
VIN = 3.6 V, VCE = 0 V
RONP
On Resistance of Pch Tr.
RONN
On Resistance of Nch Tr.
Maxduty
V
0.4
1.0
V
V
0.4
V
30
Ω
VIN = 3.6 V, ILX = −100 mA
0.34
Ω
VIN = 3.6 V, ILX = −100 mA
0.43
Ω
Oscillator Maximum Duty
Cycle
100
%
150
310
s
tstart
Soft-start Time
VIN = VCE = 3.6 V or VSET +1 V
ILXLIM
Lx Current Limit
VIN = VCE = 3.6 V or VSET +1 V
700
900
tprot
Protection Delay Time
VIN = VCE = 3.6 V or VSET +1 V
0.5
1.5
5
ms
VUVLO1
UVLO Detector Threshold
VIN = VCE
1.9
2.0
2.1
V
VUVLO2
UVLO Released Voltage
VIN = VCE
2.0
2.1
2.2
V
mA
All test items listed under ELECTRICAL CHARACTERISTICS are done under the pulse load condition (Tj ≈ Ta = 25°C) except
Output Voltage Temperature Coefficient.
Test circuit is "OPEN LOOP" and AGND = PGND = 0 V unless otherwise specified.
*1
Only for RP504xxx1A/B/C with no auto-discharge
*2
Only for RP504xxx1D with auto-discharge
8
RP504x
NO.EA-259-150130
RP504xxxxB, RP504xxxxC Electrical Characteristics
Symbol
Item
Conditions
VIN
Operating Input Voltage
Typ.
Max.
2.3
5.5
VOUT < 1.0
2.3
4.5
VOUT ≥ 1.2 V
x0.985
x1.015
VOUT < 1.2 V
−0.018
+0.018
VIN = VCE = 3.6 V
or VSET +1 V
Output Voltage Temperature
Coefficient
−40°C ≤ Ta ≤ 85°C
fosc
Oscillator Frequency
VIN = VCE = 3.6 V or VSET +1 V
IDD1
Supply Current 1
VIN = VCE = 5.5 V,
VOUT = VSET 0.8
IDD2
Supply Current 2
VIN = VCE = VOUT
= 5.5 V
Istandby
Standby Current
VIN = 5.5 V, VCE = 0 V
ICEH
CE "H" Input Voltage
VIN = VCE = 5.5 V
ICEL
CE "L" Input Voltage
IVOUTH
IVOUTL
VOUT/Ta
Min.
VOUT ≥ 1.0
Output Voltage
VOUT
(Ta = 25°C)
40
1.95
Unit
V
V
ppm/°C
2.25
2.55
MHz
400
800
A
RP504xxx1B
25
40
RP504xxx1C
400
800
0
5
A
−1
0
1
A
VIN = 5.5 V, VCE = 0 V
−1
0
1
A
VOUT "H" Input Current
VIN = VOUT = 5.5 V, VCE = 0 V
−1
0
1
A
VOUT "L" Input Current
VIN = 5.5 V, VCE = VOUT = 0 V
−1
0
1
A
ILXLEAKH
LX Leakage Current "H"
VIN = VLX = 5.5 V, VCE = 0 V
−1
0
5
A
ILXLEAKL
LX Leakage Current "L"
VIN = 5.5 V, VCE = VLX = 0 V
−5
0
1
A
VCEH
CE "H" Input Voltage
VIN = 5.5 V
1.0
VCEL
CE "L" Input Voltage
VIN =2.3 V
RONP
On Resistance of Pch Tr.
VIN =3.6 V, ILX = −100 mA
0.34
Ω
RONN
On Resistance of Nch Tr.
VIN =3.6 V, ILX = −100 mA
0.43
Ω
Maxduty
Oscillator Maximum Duty
Cycle
A
V
0.4
100
V
%
150
310
s
tstart
Soft-start Time
VIN = VCE = 3.6 V or VSET +1 V
ILXLIM
LX Current Limit
VIN = VCE = 3.6 V or VSET +1 V
700
900
tprot
Protection Delay Time
VIN = VCE = 3.6 V or VSET +1 V
0.5
1.5
5
ms
VUVLO1
UVLO Detector Threshold
VIN = VCE
1.9
2.0
2.1
V
VUVLO2
UVLO Released Voltage
VIN = VCE
2.0
2.1
2.2
V
mA
All test items listed under ELECTRICAL CHARACTERISTICS are done under the pulse load condition (Tj ≈ Ta = 25°C) except
Output Voltage Temperature Coefficient.
Test circuit is "OPEN LOOP" and AGND = PGND = 0 V unless otherwise specified.
9
RP504x
NO.EA-259-150130
TYPICAL APPLICATION
Control
VOUT
CE
RP504N
GND
Load
VIN
VIN
LX
COUT 4.7F
L 2.2H
CIN 2.2F
RP504N Typical Application: MODE Pin not included
Control
VOUT
CE
RP504L/K
Control
*1
MODE
GND
Load
VIN
VIN
LX
COUT 4.7F
L 2.2H
CIN 2.2F
RP504K/L Typical Application: MODE Pin included
*1
MODE = “H”: forced PWM control, MODE = “L”: PWM/VFM auto switching control
Recommended Components
Symbol
Capacitance
Type
2.2 µF
CIN
2.2 µF x 2
Manufacturer
C1608JB0J225K(TDK)
Ceramic Capacitor
4.7 µF
COUT
4.7 µF
Ceramic Capacitor
L
2.2 µH
Inductor
C1005JB0J225K (TDK)
JMK105BJ225MV (Taiyo Yuden)
C1005X5R0J475M (TDK)
JMK105BJ475MV (Taiyo Yuden)
C1608JB0J475K (TDK)
GRM188B30J475KE18 (Murata)
MIPSZ2520D2R2 (FDK)
MIPS2520D2R2 (FDK)
MLP2520S2R2M (TDK)
VLS252010T-2R2M (TDK)
10
RP504x
NO.EA-259-150130
TECHNICAL NOTES
The performance of power supply circuits using this IC largely depends on the peripheral circuits. Please be very
careful when setting the peripheral parts. When designing the peripheral circuits of each part, PCB patterns, and
this IC, please do not exceed the rated values (Voltage, Current, Power).
Ensure the VIN and GND lines are sufficiently robust. A large switching current flows through the GND lines,
the VDD line, the VOUT line, an inductor, and LX. If their impedance is too high, noise pickup or unstable
operation may result. Set the external components as close as possible to the IC and minimize the wiring
between the components and the IC, especially between a capacitor (CIN) and the VIN pin. The wiring between
VOUT and load and between L and VOUT should be separated.
Choose a low ESR ceramic capacitor. The capacitance of CIN should be more than or equal to 2.2 µF. The
capacitance of a capacitor (COUT) should be between 4.7 µF to 10 µF.
The Inductance value should be set within the range of 2.2 µH to 4.7 µH. However, the inductance value is
limited by output voltage. Refer to the table below. The phase compensation of this IC is designed according
to the COUT and L values. Choose an inductor that has small DC resistance, has enough allowable current
and is hard to cause magnetic saturation. If the inductance value of an inductor is extremely small, the peak
current of LX may increase. The increased LX peak current reaches “LX limit current” to trigger overcurrent
protection circuit even if the load current is less than 600 mA.
Overcurrent protection circuit, Latch-type protection circuit may be affected by self-heating and heat radiation
environment.
11
RP504x
NO.EA-259-150130
OPERATION OF STEP-DOWN CONVERTER AND OUTPUT CURENT
The step-down DC/DC converter charges energy in the inductor when LX Tr. turns “ON”, and discharges the
energy from the inductor when LX Tr. turns “OFF” and operates with less energy loss, so that a lower output
voltage (VOUT) than the input voltage (VIN) can be obtained. The operation of the step-down DC/DC converter is
explained in the following figures.
IL
ILmax
i1
VIN
Pch Tr
Nch Tr
VOUT
L
i2
ILmin
i1
topen
i2
CL
GND
ton
toff
T＝1/fosc
Figure 1. Basic Circuit
Figure 2. Inductor Current (IL) flowing through Inductor
P-channel Tr. turns “ON” and IL (i1) flows, L is charged with energy. At this moment, i1 increases from
the minimum inductor current (ILmin), which is 0 A, and reaches the maximum inductor current (ILmax)
in proportion to the on-time period (ton) of P-channel Tr.
Step2. When P-channel Tr. turns “OFF”, L tries to maintain IL at ILmax, so L turns N-channel Tr. “ON” and IL
(i2) flows into L.
Step3. i2 decreases gradually and reaches ILmin after the open-time period (topen) of N-channel Tr., and then
N-channel Tr. turns “OFF”. This is called discontinuous current mode.
As the output current (IOUT) increases, the off-time period (toff) of P-channel Tr. runs out before IL reaches
ILmin. The next cycle starts, and P-channel Tr. turns “ON” and N-channel Tr. turns “OFF”, which means
IL starts increasing from ILmin. This is called continuous current mode.
Step1.
In the case of PWM mode, VOUT is maintained by controlling ton. During the PWM mode, the oscillator frequency
(fosc) is constantly maintained.
As shown in Figure 2, when the step-down DC/DC operation is constant, ILmin and ILmax during ton of P-channel
Tr. would be the same as ILmin and ILmax during toff of the P-channel Tr.
The current differential between ILmax and ILmin is described as I.
I = ILmax − ILMIN = VOUT topen / L = (VIN − VOUT) ton / L ....................................... Equation 1
However,
T = 1 / fosc = ton + toff
Duty (%) = ton / T 100 = ton fosc 100
topen ≤ toff
In Equation 1, “VOUT topen / L” shows the amount of current change in “OFF” state. Also, “(VIN − VOUT) ton /
L” shows the amount of current change at “ON” state.
12
RP504x
NO.EA-259-150130
DISCONTINUOUS MODE AND CONTINUOUS MODE
As illustrated in Figure 3., when IOUT is relatively small, topen < toff. In this case, the energy charged into L during
ton will be completely discharged during toff, as a result, ILMIN = 0. This is called discontinuous mode.
When IOUT is gradually increased, eventually topen = toff and when IOUT is increased further, eventually ILMIN > 0.
This is called continuous mode.
IL
ILMAX
IL
ILMAX
ILMIN
ILMIN
topen
t
ton
ICONST
toff
ton
T = 1 / fosc
Figure 3. Discontinuous Mode
t
toff
T = 1 / fosc
Figure 4. Continuous Mode
In the continuous mode, the solution of Equation 1 is described as tonc.
tonc = T VOUT / VIN ............................................................................................................... Equation 2
When ton < tonc, it indicates discontinuous mode, and when ton = tonc, it indicates continuous mode.
13
RP504x
NO.EA-259-150130
OUTPUT CURRENT AND SELECTION OF EXTERNAL COMPONENTS
The following equations explain the relationship between output current and peripheral components used in the
diagrams in TYPICAL APPLICATIONS.
Ripple Current P-P value is described as IRP, ON resistance of P-channel Tr. is described as RONP, ON
resistance of N-channel Tr. is described as RONN, and DC resistor of the inductor is described as RL.
VIN = VOUT + (RONP + RL) IOUT + L IRP / ton .............................................................. Equation 3
Second, when P-channel Tr. is “OFF” (N-channel Tr. Is “ON”), the following equation is satisfied.
L IRP / toff = RONN IOUT + VOUT + RL IOUT ............................................................... Equation 4
Put Equation 4 into Equation 3 to solve ON duty of P-channel Tr. (DON = ton / (toff + ton)):
DON = (VOUT + RONN IOUT + RL IOUT) / (VIN + RONN IOUT − RONP IOUT) ................... Equation 5
Ripple Current is described as follows:
IRP = (VIN − VOUT − RONP IOUT − RL IOUT) DON / fosc / L ......................................... Equation 6
Peak current that flows through L, and LX Tr. is described as follows:
ILXMAX = IOUT + IRP / 2 .................................................................................................... Equation 7
Consider ILXMAX when setting conditions of input and output, as well as selecting the external components.
The above calculation formulas are based on the ideal operation of the ICS in continuous mode.
14
RP504x
NO.EA-259-150130
TIMING CHART
SOFT-START TIME
Starting-up with CE Pin
The IC starts to operate when the CE pin voltage (VCE) exceeds the threshold voltage. The threshold voltage is
preset between CE “H” input voltage (VCEH) and CE “L” input voltage (VCEL).
After the start-up of the IC, soft-start circuit starts to operate. Then, after a certain period of time, the reference
voltage (VREF) in the IC gradually increases up to the specified value.
CE Pin Input Voltage
(VCE)
IC Internal Reference Voltage
(VREF)
Lx Voltage
(VLX)
VCEH
Threshold Level
VCEL
Soft-start Time
Soft-start Circuit
operation starts.
IC operates with PWM mode
during Soft-start time.
Output Voltage
(VOUT)
Depending on Power Supply,
Load Current, External Components
Soft-start time starts when soft-start circuit is activated, and ends when the reference voltage reaches the
specified voltage.
Soft start time is not always equal to the turn-on speed of the step-down DC/DC converter. Please note that the
turn-on speed could be affected by the power supply capacity, the output current, the inductance value and the
COUT value.
Starting-up with Power Supply
After the power-on, when VIN exceeds the UVLO released voltage (VUVLO2), the IC starts to operate. Then, softstart circuit starts to operate and after a certain period of time, VREF gradually increases up to the specified value.
Soft-start time starts when soft-start circuit is activated, and ends when VREF reaches the specified voltage.
VSET
VUVLO2
Input Voltage
(VIN)
VUVLO1
Soft-start Time
IC Internal Reference Voltage
(VREF)
Lx Voltage
(VLX)
IC operates with PWM mode during Soft-start time.
VSET
Output Voltage
(VOUT)
Depending on Power Supply, Load Current,
External Components
Please note that the turn-on speed of VOUT could be affected by the power supply capacity, the output current,
the inductance value, the COUT value and the turn-on speed of VIN determined by CIN.
15
RP504x
NO.EA-259-150130
Under Voltage Lockout (UVLO) Circuit
If VIN becomes lower than VSET, the step-down DC/DC converter stops the switching operation and ON duty
becomes 100%, and then VOUT gradually drops according to VIN.
If the VIN becomes lower than the UVLO detector threshold (VUVLO1), the UVLO circuit starts to operate, VREF
stops, and P-channel and N-channel built-in switch transistors turn “OFF”. As a result, VOUT drops according to
the COUT capacitance value and the load.
To restart the operation, VIN needs to be higher than VUVLO2. The timing chart below shows the voltage shifts of
VREF, VLX and VOUT when VIN value is varied.
Input Voltage
(VIN)
VSET
VUVLO2
VUVLO1
Soft-start Time
IC Internal Reference Voltage
(VREF)
Lx Voltage
(VLX)
Output Voltage
(VOUT)
VSET
Depending on Power Supply, Load Current,
External Components
Falling edge (operating) and rising edge (releasing) waveforms of VOUT could be affected by the initial voltage
of COUT and the output current of VOUT.
16
RP504x
NO.EA-259-150130
Overcurrent Protection Circuit, Latch Type Protection Circuit
Overcurrent protection circuit supervises the inductor peak current (the peak current flowing through Pch Tr.) in
each switching cycle, and if the current exceeds the LX current limit (ILXLIM), it turns off Pch Tr. ILXLIM of the RP504x
is set to Typ.900 mA.
Latch type protection circuit latches the built-in driver to the OFF state and stops the operation of the step-down
DC/DC converter if the overcurrent status continues or VOUT continues being the half of the setting voltage for
equal or longer than protection delay time (tprot).
Please note that ILXLIM and tprot could be easily affected by self-heating or ambient environment. If the VIN drops
dramatically or becomes unstable due to short-circuit, protection operation and tprot could be affected.
Protection Delay Time (tprot)
Lx Current
Lx Current Limit (ILXlim)
Pch Tr. Current
Lx Voltage
(VLX)
To release the latch type protection circuit, restart the IC by inputting "L" signal to the CE pin, or restart the IC
with power-on or make the supply voltage lower than VUVLO1.
The timing chart below shows the voltage shift of VCE, VLX and VOUT when the IC status is changed by the
following orders: VIN rising → stable operation → high load → CE reset → stable operation → VIN falling → VIN
recovering (UVLO reset) → stable operation.
(1)(2) If the large current flows through the circuit or if the IC goes into low VOUT condition due to short-circuit or
other reasons, the latch type protection circuit latches the built-in driver to “OFF” state after tprot. Then, VLX
becomes "L" and VOUT turns “OFF”.
(3) The latch type protection circuit is released by CE reset, which puts the IC into "L" once with the CE pin and
back into "H".
(4) The latch type protection circuit is released by UVLO reset, which makes VIN lower than VUVLO1.
(1)
(3)
(2)
(4)
SET
Input Voltage UVLO Released VoltageV(V
UVLO2)
(VIN)
UVLO Detector Threshold (VUVLO1)
CE Pin
Input Voltage
(VCE)
Lx Voltage
(VLX)
Output Voltage
(VOUT)
UVLO Reset
VSET
Threshold Level
CE Reset
Protection Delay Time
Protection Delay Time
VSET
VSET
Latch-type Protection
Stable
Operation
Soft-start Time
Stable
Operation
Soft-start Time
Latch-type Protection
Stable
Operation
Soft-start Time
17
RP504x
NO.EA-259-150130
PACKAGE INFORMATION
POWER DISSIPATION (DFN(PLP)1216-6F)
Power Dissipation (PD) of the package is dependent on PCB material, layout, and environmental conditions.
The following conditions are used in this measurement.
Measurement Conditions
Standard Land Pattern
Environment
Mounting on Board (Wind Velocity = 0 m/s)
Board Material
Glass Cloth Epoxy Plastic (Double-sided)
Board Dimensions
40 mm x 40 mm x 1.6 mm
Copper Ratio
Topside: Approx. 50%, Backside: Approx. 50%
Through-holes
0.3 mm x 26 pcs
Measurement Result
(Ta = 25C, Tjmax = 125C)
Standard Land Pattern
Power Dissipation
385 mW
ja = (125 − 25 °C) / 0.385W = 260 °C/W
Thermal Resistance
jc = 30°C/W
40
600
On Board
500
385
400
300
40
Power Dissipation PD (mW)
700
200
100
0
0
25
50
75 85 100
125
IC Mount Area (Unit: mm)
Ambient Temperature (C)
Power Dissipation vs. Ambient Temperature
Measurement Board Pattern
18
RP504x
NO.EA-259-150130
PACKAGE DIMENSIONS (DFN(PLP)1216-6F)
0.340.05
A
B
1.60
0.05 M AB
0.300.05
0.150.025
0.300.05
4
5
6
3
2
1
x4
0.020.05
0.4Max.
0.50
S
0.50
0.400.05
INDEX
0.05
0.350.05
1.20
0.05
C0.10
Bottom View
0.05 S
(Unit : mm)
DFN(PLP)1216-6F Package Dimensions
MARK SPECIFICATION (DFN(PLP)1216-6F)
: Product Code … Refer to MARK SPECIFICATION TABLE (DFN(PLP)1216-6F).
: Lot Number … Alphanumeric Serial Number
DFN(PLP)1216-6F Mark Specification
19
RP504x
NO.EA-259-150130
MARK SPECIFICATION TABLE (DFN(PLP)1216-6F)
RP504K
Product Name
RP504K081A
RP504K091A
RP504K101A
RP504K111A
RP504K121A
RP504K131A
RP504K141A
RP504K151A
RP504K161A
RP504K171A
RP504K181A
RP504K191A
RP504K201A
RP504K211A
RP504K221A
RP504K231A
RP504K241A
RP504K251A
RP504K261A
RP504K271A
RP504K281A
RP504K291A
RP504K301A
RP504K311A
RP504K321A
RP504K331A
RP504K121A5
RP504K131A5
RP504K121A2
RP504K101A5
DA08
DA09
DA10
DA11
DA12
DA13
DA14
DA15
DA16
DA17
DA18
DA19
DA20
DA21
DA22
DA23
DA24
DA25
DA26
DA27
DA28
DA29
DA30
DA31
DA32
DA33
DA01
DA02
DA03
DA04
Product Name
RP504K081D
RP504K091D
RP504K101D
RP504K111D
RP504K121D
RP504K131D
RP504K141D
RP504K151D
RP504K161D
RP504K171D
RP504K181D
RP504K191D
RP504K201D
RP504K211D
RP504K221D
RP504K231D
RP504K241D
RP504K251D
RP504K261D
RP504K271D
RP504K281D
RP504K291D
RP504K301D
RP504K311D
RP504K321D
RP504K331D
RP504K121D5
RP504K131D5
RP504K121D2
RP504K101D5
DB08
DB09
DB10
DB11
DB12
DB13
DB14
DB15
DB16
DB17
DB18
DB19
DB20
DB21
DB22
DB23
DB24
DB25
DB26
DB27
DB28
DB29
DB30
DB31
DB32
DB33
DB01
DB02
DB03
DB04
20
RP504x
NO.EA-259-150130
POWER DISSIPATION (DFN1616-6B)
Power Dissipation (PD) of the package is dependent on PCB material, layout, and environmental conditions.
The following conditions are used in this measurement.
Measurement Conditions
Standard Land Pattern
Environment
Mounting on Board (Wind Velocity = 0 m/s)
Board Material
Glass Cloth Epoxy Plastic (Double-sided)
Board Dimensions
40 mm x 40 mm x 1.6 mm
Copper Ratio
Topside: Approx. 50%, Backside: Approx. 50%
Through-holes
0.5 mm x 32 pcs
Measurement Result
(Ta = 25C, Tjmax = 125C)
Standard Land Pattern
Power Dissipation
Power Dissipation PD (mW)
Thermal Resistance
700
640
600
640 mW
ja = (125 − 25C) / 0.64 W = 156C/W
jc = 23 C/W
40
On Board
500
400
40
300
200
100
0
0
25
50
75 85 100
125
150
IC Mount Area (Unit: mm)
Ambient Temperature (C)
Power Dissipation vs. Ambient Temperature
Measurement Board Pattern
21
RP504x
NO.EA-259-150130
PACKAGE DIMENSIONS (DFN1616-6B)
1.300.05
B
1.60
0.05
0.700.05
X4
4
6
0.250.05
1.60
(3X0.15)
A
*1
INDEX
0.4max.
0.10.05
3
0.5
0.200.05
1
0.05 M AB
(Unit: mm)
S
0.05 S
*1
The tab on the bottom of the package enhances thermal
performance and is electrically connected to GND
(substrate level). It is recommended that the tab be
connected to the ground plane on the board. If not, the
tab can be left open.
DFN1616-6B Package Dimensions
MARK SPECIFICATION (DFN1616-6B)
: Product Code … Refer to MARK SPECIFICATION TABLE (DFN1616-6B).
: Lot Number … Alphanumeric Serial Number
DFN1616-6B Mark Specification
22
RP504x
NO.EA-259-150130
MARK SPECIFICATION TABLE (DFN1616-6B)
RP504L
Product Name
RP504L081A
RP504L091A
RP504L101A
RP504L111A
RP504L121A
RP504L131A
RP504L141A
RP504L151A
RP504L161A
RP504L171A
RP504L181A
RP504L191A
RP504L201A
RP504L211A
RP504L221A
RP504L231A
RP504L241A
RP504L251A
RP504L261A
RP504L271A
RP504L281A
RP504L291A
RP504L301A
RP504L311A
RP504L321A
RP504L331A
RP504L121A5
RP504L131A5
RP504L121A2
RP504L101A5
AZ08
AZ09
AZ10
AZ11
AZ12
AZ13
AZ14
AZ15
AZ16
AZ17
AZ18
AZ19
AZ20
AZ21
AZ22
AZ23
AZ24
AZ25
AZ26
AZ27
AZ28
AZ29
AZ30
AZ31
AZ32
AZ33
AZ01
AZ02
AZ03
AZ04
Product Name
RP504L081D
RP504L091D
RP504L101D
RP504L111D
RP504L121D
RP504L131D
RP504L141D
RP504L151D
RP504L161D
RP504L171D
RP504L181D
RP504L191D
RP504L201D
RP504L211D
RP504L221D
RP504L231D
RP504L241D
RP504L251D
RP504L261D
RP504L271D
RP504L281D
RP504L291D
RP504L301D
RP504L311D
RP504L321D
RP504L331D
RP504L121D5
RP504L131D5
RP504L121D2
RP504L101D5
CZ08
CZ09
CZ10
CZ11
CZ12
CZ13
CZ14
CZ15
CZ16
CZ17
CZ18
CZ19
CZ20
CZ21
CZ22
CZ23
CZ24
CZ25
CZ26
CZ27
CZ28
CZ29
CZ30
CZ31
CZ32
CZ33
CZ01
CZ02
CZ03
CZ04
23
RP504x
NO.EA-259-150130
POWER DISSIPATION (SOT-23-5)
Power Dissipation (PD) of the package is dependent on PCB material, layout, and environmental conditions.
The following conditions are used in this measurement. This data is taken from SOT-23-6.
Measurement Conditions
Standard Land Pattern
Environment
Mounting on Board (Wind Velocity = 0 m/s)
Board Material
Glass Cloth Epoxy Plastic (Double-sided)
Board Dimensions
40 mm x 40 mm x 1.6 mm
Copper Ratio
Top side: Approx. 50%, Back side: Approx. 50%
Through-holes
0.5 mm x 44 pcs
Measurement Result
(Ta = 25C, Tjmax = 125C)
Standard Land Pattern
Free Air
Power Dissipation
420 mW
250 mW
Thermal Resistance
ja = (125 − 25C) / 0.42 W = 238C/W
400C/W
40
500
On Board
420
400
300
Free Air
250
40
Power Dissipation PD (mW)
600
200
100
0
0
25
50
75 85 100
125
Ambient Temperature (C)
Power Dissipation vs. Ambient Temperature
150
IC Mount Area (Unit: mm)
Measurement Board Pattern
24
RP504x
NO.EA-259-150130
PACKAGE DIMENSIONS (SOT-23-5)
2.9±0.2
1.1±0.1
1.9±0.2
(0.95)
0.8±0.1
(0.95)
4
1
2
0～0.1
0.2min.
2.8±0.3
+0.2
1.6 0.1
5
3
+0.1
0.15 0.05
0.4±0.1
(Unit: mm)
SOT-23-5 Package Dimensions
MARK SPECIFICATION (SOT-23-5)
: Product Code … Refer to MARK SPECIFICATION TABLE (SOT-23-5).
: Lot Number … Alphanumeric Serial Number
5
4
1
2
3
SOT-23-5 Mark Specification
25
RP504x
NO.EA-259-150130
MARK SPECIFICATION TABLE (SOT-23-5)
RP504N
Product Name
RP504N081B
RP504N091B
RP504N101B
RP504N111B
RP504N121B
RP504N131B
RP504N141B
RP504N151B
RP504N161B
RP504N171B
RP504N181B
RP504N191B
RP504N201B
RP504N211B
RP504N221B
RP504N231B
RP504N241B
RP504N251B
RP504N261B
RP504N271B
RP504N281B
RP504N291B
RP504N301B
RP504N311B
RP504N321B
RP504N331B
RP504N121B5
RP504N131B5
M08
M09
M10
M11
M12
M13
M14
M15
M16
M17
M18
M19
M20
M21
M22
M23
M24
M25
M26
M27
M28
M29
M30
M31
M32
M33
M01
M02
Product Name
RP504N081C
RP504N091C
RP504N101C
RP504N111C
RP504N121C
RP504N131C
RP504N141C
RP504N151C
RP504N161C
RP504N171C
RP504N181C
RP504N191C
RP504N201C
RP504N211C
RP504N221C
RP504N231C
RP504N241C
RP504N251C
RP504N261C
RP504N271C
RP504N281C
RP504N291C
RP504N301C
RP504N311C
RP504N321C
RP504N331C
RP504N121C5
RP504N131C5
N08
N09
N10
N11
N12
N13
N14
N15
N16
N17
N18
N19
N20
N21
N22
N23
N24
N25
N26
N27
N28
N29
N30
N31
N32
N33
N01
N02
26
RP504x
NO.EA-259-150130
TYPICAL CHARACTERISTICS
Note: Typical Characteristics are intended to be used as reference data; they are not guaranteed.
1) Output Voltage vs. Output Current
RP504x
VOUT = 0.8 V
RP504x
MODE = “L”PWM/VFM Auto Switching Control
MODE = “H” Forced PWM Control
0.820
0.815
VIN=3.6V
0.810
VIN=4.5V
0.805
0.800
0.795
0.790
0.785
Output Voltage V OUT (V)
Output Voltage V OUT (V)
0.820
0.780
0.01
0.815
VIN=3.6V
0.810
VIN=4.5V
0.805
0.800
0.795
0.790
0.785
0.780
0.1
1
10
100
0
100
Output Current IOUT (m A)
RP504x
VOUT = 1.2 V
1.210
VIN=5.0V
1.205
1.200
1.195
1.190
1.185
Output Voltage V OUT (V)
Output Voltage V OUT (V)
VIN=3.6V
1.180
1.215
VIN=3.6V
1.210
VIN=5.0V
1.205
1.200
1.195
1.190
1.185
1.180
0.1
1
10
Output Current IOUT (m A)
RP504x
100
0
VOUT = 1.8 V
100 200 300 400 500
Output Current IOUT (m A)
RP504x
MODE = “L”PWM/VFM Auto Switching Control
600
VOUT = 1.8 V
MODE = “H” Forced PWM Control
1.830
VIN=3.6V
VIN=5.0V
1.810
1.800
1.790
Output Voltage V OUT (V)
1.830
Output Voltage V OUT (V)
VOUT = 1.2 V
1.220
1.215
VIN=3.6V
1.820
VIN=5.0V
1.810
1.800
1.790
1.780
1.780
0.01
600
MODE = “H” Forced PWM Control
1.220
1.820
200 300 400 500
Output Current IOUT (m A)
RP504x
MODE = “L”PWM/VFM Auto Switching Control
0.01
VOUT = 0.8 V
0.1
1
10
Output Current IOUT (m A)
100
0
100
200
300
400
500
600
Output Current IOUT (m A)
27
RP504x
NO.EA-259-150130
RP504x VOUT = 3.3 V
MODE = “L”PWM/VFM Auto Switching Control
RP504x VOUT = 3.3 V
MODE = “H” Forced PWM Control
3.320
VIN=4.3V
3.310
VIN=5.0V
3.300
3.290
3.280
VIN=4.3V
Output Voltage V OUT (V)
Output Voltage V OUT (V)
3.320
3.310
VIN=5.0V
3.300
3.290
3.280
3.270
3.270
0.01
0.1
1
10
Output Current IOUT (m A)
0
100
100 200 300 400 500
Output Current IOUT (m A)
600
2) Output Voltage vs. Input Voltage
RP504x VOUT = 1.2 V
MODE = “H” Forced PWM Control
0.820
1.220
0.815
1.215
Output Voltage V OUT (V)
Output Voltage V OUT (V)
RP504x VOUT = 0.8 V
MODE = “H” Forced PWM Control
0.810
0.805
0.800
IOUT=1m A
0.795
IOUT=50m A
0.790
IOUT=250m A
0.785
0.780
1.210
1.205
1.200
1.195
IOUT=1m A
1.190
IOUT=50m A
1.185
IOUT=250m A
1.180
2
2.5
3
3.5
4
4.5
2
2.5
3
Input Voltage VIN (V)
RP504x VOUT = 1.8 V
MODE = “H” Forced PWM Control
Output Voltage V OUT (V)
Output Voltage V OUT (V)
1.82
1.81
1.8
IOUT=1m A
IOUT=50m A
IOUT=250m A
1.78
1.77
2
2.5
3
3.5
4
4.5
Input Voltage VIN (V)
4
4.5
5
5.5
RP504x VOUT = 3.3 V
MODE = “H” Forced PWM Control
1.83
1.79
3.5
Input Voltage VIN (V)
5
5.5
3.35
3.34
3.33
3.32
3.31
3.3
3.29
3.28
3.27
IOUT=1m A
IOUT=50m A
IOUT=250m A
3.26
3.25
3.5
4
4.5
5
5.5
Input Voltage VIN (V)
28
RP504x
NO.EA-259-150130
3) Output Voltage vs. Temperature
Output Voltage V OUT (V)
1.830
1.820
VIN=3.6V
1.810
1.800
1.790
1.780
1.770
-50
-25
0
25
50
75
Tem perature Ta(°C)
100
4) Efficiency vs. Output Current
RP504x
VOUT = 0.8 V
100
Efficiency (%)
80
100
VIN=4.5V, VMODE=0V
90
VIN=3.6V, VMODE=0V
70
60
50
VIN=VMODE=4.5V
40
30
VIN=VMODE=3.6V
20
VIN=3.6V, VMODE=0V
70
60
50
40
VIN=VMODE=5.0V
30
VIN=VMODE=3.6V
10
0.1
1
10
100
Output Current IOUT (mA)
0
0.01
1000
VOUT = 1.8 V
VIN=5.0V, VMODE=0V
100
VIN=3.6V, VMODE=0V
90
80
70
60
50
40
VIN=VMODE=5.0V
30
20
VIN=VMODE=3.6V
10
0
0.01
0.1
1
10
100
1000
Output Current IOUT (mA)
0.1
1
10
100
Output Current IOUT (mA)
RP504x
Efficiency (%)
RP504x
Efficiency (%)
VIN=5.0V, VMODE=0V
20
10
0
0.01
VOUT = 1.2 V
80
Efficiency (%)
90
RP504x
1000
VOUT = 3.3 V
VIN=5.0V, VMODE=0V
100 VIN=4.3V, VMODE=0V
90
80
70
60
50
VIN=VMODE=4.3V
40
30
20
VIN=VMODE=3.6V
10
0
0.01
0.1
1
10
100
1000
Output Current IOUT (mA)
29
RP504x
NO.EA-259-150130
5) Supply Current vs. Temperature
6) Supply Current vs. Input Voltage
RP504x VOUT = 1.8 V (VIN = 5.5 V)
MODE = “L”PWM/VFM Auto Switching Control
RP504x VOUT = 1.8 V
MODE = “L”PWM/VFM Auto Switching Control
40
35
Clos ed Loop
30
Open Loop
Supply Current (µA)
Supply Current (µA)
40
25
20
15
10
35
Clos ed Loop
30
Open Loop
25
20
15
10
-50
-25
0
25
50
75
100
2
2.5
3
3.5
4
4.5
Input Voltage VIN (V)
Tem perature Ta(°C)
5
5.5
7) Output Voltage Waveform
RP504x VOUT = 0.8 V (VIN = 3.6 V)
MODE = “L”PWM/VFM Auto Switching Control
RP504x VOUT = 0.8 V (VIN = 3.6 V)
MODE = “H” Forced PWM Control
0
5
10
Time t (µs)
15
20
Output Voltage
IL
100
50
0
-50
-100
0
RP504x VOUT = 1.2V (VIN = 3.6 V)
MODE = “L”PWM/VFM Auto Switching Control
300
200
100
0
-100
0
5
10
Time t (µs)
15
20
1
2
3
4 5 6 7
Time t (µs)
8
9 10
RP504x VOUT = 1.2 V (VIN = 3.6 V)
MODE = “H” Forced PWM Control
IOUT=10mA
0.04
0.03
0.02
0.01
0.00
-0.01
Output Ripple Voltage (AC)
Vripple (V)
Output Ripple Voltage (AC)
Vripple (V)
Output Voltage
IL
Inductor Current IL (mA)
IOUT=10mA
0.04
0.03
0.02
0.01
0.00
-0.01
Inductor Current IL (mA)
300
200
100
0
-100
IOUT=10mA
0.04
0.03
0.02
0.01
0.00
-0.01
Output Voltage
Inductor Current IL (mA)
IL
Output Ripple Voltage (AC)
Vripple (V)
Output Voltage
Inductor Current IL (mA)
Output Ripple Voltage (AC)
Vripple (V)
IOUT=10mA
0.04
0.03
0.02
0.01
0.00
-0.01
IL
100
50
0
-50
-100
0
1
2
3
4 5 6 7
Time t (µs)
8
9 10
30
RP504x
NO.EA-259-150130
VOUT = 1.8 V (VIN = 3.6 V)
RP504x
MODE = “L”PWM/VFM Auto Switching Control
MODE = “H” Forced PWM Control
300
200
100
0
-100
0
5
RP504x
10
Time t (µs)
15
IOUT=10mA
0.04
0.03
0.02
0.01
0.00
-0.01
Output Voltage
IL
100
50
0
-50
-100
0
20
VOUT = 3.3 V (VIN = 5.0 V)
3
4 5 6 7
Time t (µs)
8
9 10
VOUT = 3.3 V (VIN = 5.0 V)
MODE = “H” Forced PWM Control
IOUT=10mA
Output Voltage
IL
0
300
200
100
0
-100
5
10
Time t (µs)
15
IOUT=10mA
Output Ripple Voltage (AC)
Vripple (V)
0.04
0.03
0.02
0.01
0.00
-0.01
Inductor Current IL (mA)
Output Ripple Voltage (AC)
Vripple (V)
2
RP504x
MODE = “L”PWM/VFM Auto Switching Control
0.04
0.03
0.02
0.01
0.00
-0.01
Output Voltage
IL
200
150
100
50
0
-50
-100
0
20
8) Frequency vs. Temperature
1
Frequency fosc (MHz)
2.5
VIN=3.6V
2.4
2
3
4 5 6 7
Time t (µs)
8
9 10
9) Frequency vs. Input Voltage
2.5
Frequency fosc (MHz)
1
Inductor Current IL (mA)
IL
Output Ripple Voltage (AC)
Vripple (V)
Output Ripple Voltage (AC)
Vripple (V)
Output Voltage
Inductor Current IL (mA)
IOUT=10mA
0.04
0.03
0.02
0.01
0.00
-0.01
VOUT = 1.8 V (VIN = 3.6 V)
Inductor Current IL (mA)
RP504x
2.3
2.2
2.1
2
-40°C
2.4
25°C
85°C
2.3
2.2
2.1
2
-50
-25
0
25
50
Tem perature Ta (°C)
75
100
2
2.5
3
3.5
4
4.5
5
5.5
Input Voltage VIN (V)
31
RP504x
NO.EA-259-150130
10) Soft Start Time vs. Temperature
Soft Start Time tstart (µs)
220
210
200
190
180
170
-50
-25
0
25
50
75
Tem perature Ta(°C)
100
11) UVLO Detector Threshold / Released Voltage vs. Temperature
UVLO Detector Threshold Voltage
UVLO Released Voltage
2.3
UVLO Voltage V UVLO2 (V)
UVLO Voltage V UVLO1 (V)
2.3
2.2
2.1
2.0
1.9
2.2
2.1
2.0
1.9
-50
-25
0
25
50
Tem perature Ta(°C)
75
100
-50
-25
0
25
50
75
Tem perature Ta(°C)
100
12) CE Input Voltage vs. Temperature
CE “H” Input Voltage (VIN = 5.5 V)
CE “H” Input Voltage (VIN = 2.3 V)
(V)
1
0.9
CE
0.8
CE Input Voltage V
CE Input Voltage V
CE
(V)
1
0.7
0.6
0.5
0.4
0.9
0.8
0.7
0.6
0.5
0.4
-50
-25
0
25
50
Tem perature Ta(°C)
75
100
-50
-25
0
25
50
Tem perature Ta(°C)
75
100
32
RP504x
NO.EA-259-150130
13) LX Current Limit vs. Temperature
L X Current Limit llim (mA)
1000
950
900
850
800
-50
-25
0
25
50
75
Tem perature Ta(°C)
100
15) Pch Tr. ON Resistance vs. Temperature
0.60
ON (Ω)
0.60
0.50
0.50
Pch Tr.ONResistance R
Nch Tr.ONResistance R
ON (Ω)
14) Nch Tr. ON Resistance vs. Temperature
0.40
0.30
0.20
0.10
0
-50
-25
0
25
50
75
Tem perature Ta(°C)
0.40
0.30
0.20
0.10
0
100
-50
-25
0
25
50
75
Tem perature Ta(°C)
100
16) Load Transient Response
RP504x081x (VIN = 3.6 V)
RP504x081x (VIN = 3.6 V)
0.90
0.80
0.70
Output Voltage
0.60
200
200
0
Output Current
300mA-->1mA
0
1.00
0.90
0.80
Output Voltage
0.70
Output Current IOUT (mA)
1.00
400
Output Voltage VOUT (V)
Output Current
1mA-->300mA
MODE = “L”PWM/VFM Auto Switching Control
400
Output Current IOUT (mA)
Output Voltage VOUT (V)
MODE = “L”PWM/VFM Auto Switching Control
0.60
-10 0 10 20 30 40 50 60 70 80 90
Time t (µs)
-100
0
100 200 300 400 500 600 700 800 900
Time t (µs)
33
RP504x
NO.EA-259-150130
RP504x081x (VIN = 3.6 V)
RP504x081x (VIN = 3.6 V)
400
200
200
0
1.00
0.90
0.90
0.80
Output Voltage
0.70
0.60
0.60
-10 0 10 20 30 40 50 60 70 80 90
-10 0 10 20 30 40 50 60 70 80 90
Time t (µs)
Time t (µs)
RP504x081x (VIN = 3.6 V)
600
400
400
200
0
1.00
0.90
0.80
Output Voltage
0.70
0.60
Output Voltage VOUT (V)
Output Current
200mA-->500mA
600
Output Current IOUT (mA)
Output Voltage VOUT (V)
RP504x081x (VIN = 3.6 V)
Output Current
500mA-->200mA
0.90
0.80
Output Voltage
0.70
0.60
-10 0
RP504x121x (VIN = 3.6 V)
1.15
Output Voltage
1.10
400
200
200
0
Output Voltage VOUT (V)
1.20
MODE = “L”PWM/VFM Auto Switching Control
400
Output Current IOUT (mA)
Output Voltage VOUT (V)
1.25
10 20 30 40 50 60 70 80 90
Time t (µs)
RP504x121x (VIN = 3.6 V)
MODE = “L”PWM/VFM Auto Switching Control
1.30
0
1.00
-10 0 10 20 30 40 50 60 70 80 90
Time t (µs)
Output Current
1mA-->300mA
200
Output Current IOUT (mA)
0.70
Output Voltage
1.00
Output Current
300mA-->1mA
0
1.30
1.25
1.20
Output Voltage
1.15
Output Current IOUT (mA)
0.80
0
Output Current
300mA-->1mA
Output Current IOUT (mA)
400
Output Voltage VOUT (V)
Output Current
1mA-->300mA
MODE = “H” Forced PWM Control
Output Current IOUT (mA)
Output Voltage VOUT (V)
MODE = “H” Forced PWM Control
1.10
-10 0 10 20 30 40 50 60 70 80 90
Time t (µs)
-100
0
100 200 300 400 500 600 700 800 900
Time t (µs)
34
RP504x
NO.EA-259-150130
RP504x121x (VIN = 3.6 V)
RP504x121x (VIN = 3.6 V)
400
200
200
0
1.30
1.25
1.20
Output Voltage
1.15
Output Current
300mA-->1mA
1.30
1.25
1.20
Output Voltage
1.15
1.10
1.10
-10 0 10 20 30 40 50 60 70 80 90
-10 0 10 20 30 40 50 60 70 80 90
Time t (µs)
Time t (µs)
RP504x121x (VIN = 3.6 V)
600
400
400
0
1.30
1.25
1.15
Output Voltage
0
1.30
1.25
1.20
Output Voltage
1.15
1.10
1.10
-10 0 10 20 30 40 50 60 70 80 90
-10 0 10 20 30 40 50 60 70 80 90
Time t (µs)
Time t (µs)
RP504x181x (VIN = 3.6 V)
RP504x181x (VIN = 3.6 V)
MODE = “L”PWM/VFM Auto Switching Control
1.90
1.85
1.80
Output Voltage
1.70
400
200
200
0
Output Voltage VOUT (V)
Output Current
1mA-->300mA
MODE = “L”PWM/VFM Auto Switching Control
400
Output Current IOUT (mA)
Output Voltage VOUT (V)
200
0
Output Current
300mA-->1mA
1.90
1.85
1.80
1.75
Output Voltage
Output Current IOUT (mA)
1.20
Output Current
500mA-->200mA
Output Current IOUT (mA)
200
Output Voltage VOUT (V)
Output Current
200mA-->500mA
600
Output Current IOUT (mA)
Output Voltage VOUT (V)
RP504x121x (VIN = 3.6 V)
1.75
0
Output Current IOUT (mA)
400
Output Voltage VOUT (V)
Output Current
1mA-->300mA
MODE = “H” Forced PWM Control
Output Current IOUT (mA)
Output Voltage VOUT (V)
MODE = “H” Forced PWM Control
1.70
-10 0 10 20 30 40 50 60 70 80 90
Time t (µs)
-100
0
100 200 300 400 500 600 700 800 900
Time t (µs)
35
RP504x
NO.EA-259-150130
RP504x181x (VIN = 3.6 V)
RP504x181x (VIN = 3.6 V)
400
200
200
0
1.90
1.85
1.80
Output Voltage
1.75
1.70
0
Output Current
300mA-->1mA
1.90
1.85
1.80
Output Voltage
1.75
1.70
1.65
1.65
-10 0 10 20 30 40 50 60 70 80 90
Time t (µs)
-10 0 10 20 30 40 50 60 70 80 90
Time t (µs)
RP504x181x (VIN = 3.6 V)
200
1.85
1.80
1.75
Output Voltage
1.70
Output Current
500mA-->200mA
200
1.90
0
1.85
1.80
Output Voltage
1.75
1.70
-10 0 10 20 30 40 50 60 70 80 90
-10 0 10 20 30 40 50 60 70 80 90
Time t (µs)
Time t (µs)
RP504x331x (VIN = 5.0 V)
MODE = “L”PWM/VFM Auto Switching Control
3.50
3.40
Output Voltage
3.10
400
200
200
0
Output Voltage VOUT (V)
Output Current
1mA-->300mA
RP504x331x (VIN = 5.0 V)
MODE = “L”PWM/VFM Auto Switching Control
400
Output Current IOUT (mA)
Output Voltage VOUT (V)
400
1.65
1.65
3.20
600
Output Current
300mA-->1mA
0
3.50
3.40
3.30
Output Voltage
3.20
Output Current IOUT (mA)
0
1.90
Output Voltage VOUT (V)
400
Output Current
200mA-->500mA
Output Current IOUT (mA)
Output Voltage VOUT (V)
600
Output Current IOUT (mA)
RP504x181x (VIN = 3.6 V)
3.30
Output Current IOUT (mA)
400
Output Voltage VOUT (V)
Output Current
1mA-->300mA
MODE = “H” Forced PWM Control
Output Current IOUT (mA)
Output Voltage VOUT (V)
MODE = “H” Forced PWM Control
3.10
-10 0 10 20 30 40 50 60 70 80 90
Time t (µs)
-100
0
100 200 300 400 500 600 700 800 900
Time t (µs)
36
RP504x
NO.EA-259-150130
RP504x331x (VIN = 5.0 V)
RP504x331x (VIN = 5.0 V)
400
200
200
0
3.50
3.40
3.30
Output Voltage
3.20
3.10
3.50
3.40
3.30
Output Voltage
3.20
3.10
-10 0 10 20 30 40 50 60 70 80 90
-10 0 10 20 30 40 50 60 70 80 90
Time t (µs)
Time t (µs)
RP504x331x (VIN = 5.0 V)
400
400
200
0
3.50
3.40
3.30
Output Voltage
3.20
3.10
Output Voltage VOUT (V)
600
Output Current IOUT (mA)
Output Current
200mA-->500mA
600
200
Output Current
500mA-->200mA
0
3.50
3.40
3.30
Output Voltage
3.20
Output Current IOUT (mA)
RP504x331x (VIN = 5.0 V)
Output Voltage VOUT (V)
0
Output Current
300mA-->1mA
Output Current IOUT (mA)
400
Output Voltage VOUT (V)
Output Current
1mA-->300mA
MODE = “H” Forced PWM Control
Output Current IOUT (mA)
Output Voltage VOUT (V)
MODE = “H” Forced PWM Control
3.10
-10 0 10 20 30 40 50 60 70 80 90
-10 0 10 20 30 40 50 60 70 80 90
Time t (µs)
Time t (µs)
17) Mode Switching Waveform
RP504x (VOUT = 1.2 V, IOUT = 1 mA)
RP504x (VOUT = 1.2 V, IOUT = 1 mA)
MODE = “L” --> MODE = “H”
MODE = “H" --> MODE = “L”
1.30
1.25
1.20
1.15
-100
Output Voltage
0
100
200
Time t (µs)
300
400
Output Voltage VOUT (V)
0
Mode Input Voltage
VMODE (V)
Output Voltage VOUT (V)
Mode Input Voltage
Mode Input Voltage
Mode Input Voltage
VMODE (V)
5
5
0
1.30
1.25
1.20
1.15
-200
Output Voltage
0
200
400
600
800
Time t (µs)
37
RP504x
NO.EA-259-150130
RP504x (VOUT = 1.8 V, IOUT = 1 mA)
RP504x (VOUT = 1.8 V, IOUT = 1 mA)
MODE = "L" --> MODE = "H"
MODE = "H" --> MODE = "L"
1.90
1.85
1.80
1.75
-100
Output Voltage
0
100
200
Time t (µs)
300
400
Output Voltage VOUT (V)
0
Mode Input Voltage
VMODE (V)
Output Voltage VOUT (V)
Mode Input Voltage
Mode Input Voltage
0
1.90
1.85
1.80
1.75
-200
Output Voltage
0
200
400
600
Mode Input Voltage
VMODE (V)
5
5
800
Time t (µs)
38
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
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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
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instruments, consumer electronic products, amusement equipment etc.). Those customers intending to
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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
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the products or the technical information.
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