RICOH RP504x Technical data

RP504x Series

p

600mA∗ PWM/VFM Step-down DC/DC Converter with Synchronous Rectifier

The RP504x Series are low supply current CMOS-based PWM/VFM step-down DC/DC converters with synchronous rectifier.
RP504K/L can be switched from two control types by inputting signal to the MODE pin - forced PWM control or PWM/VFM auto
switching control in which mode automatically switches to high-efficiency VFM mode in low output current. (RP504N Series can be
selected from forced PWM control or PWM/VFM auto switching control.) RP504x includes a soft start circuit, an under-voltage lockout
circuit (UVLO), and a latch protection circuit. By simply using an inductor and capacitors as external components, a high-efficiency
step-down DC/DC converter can be easily configured. The small inductor (2.2μH) and output capacitor (4.7μH) can be used by the
switching of 2.25MHz. In addition to SOT-23-5 and DFN1616-6B packages, a 1.2mm
available.

FEATURES

• Supply Current (IDD1)·······················Typ. 400μA

• Supply Current (IDD2)·······················Typ. 25μA (VIN=VCE=VOUT=5.5V)

• Standby Current

(I

standby

)

··················Max. 5μA (VIN=5.5V, VCE=0V)

• Input Voltage Range (VIN) ··············· 2.3V to 5.5V

• Output Voltage Range (VOUT)·········· 0.8V to 3.3V (internally fixed)

• Output Voltage Accuracy ················ ± 1.5%

• Output Current (IOUT)·······················600mA

• Oscillator Frequency (fosc)···············2.25MHz

•

Oscillator Maximum Duty Cycle (Maxduty)

··Min. 100%

(VIN=VCE=5.5V, V

∗

OUT=VSET

×

0.8)

•

UVLO Detect Voltage (V

• Soft Start Time

• Coil-current Limit Circuit················· Current limit Typ. 900mA

• Latch Protection Circuit ··················

• Auto-Discharge Function················ D Version

• MODE pin······································· “H”: PWM/VFM auto switching,

• Packages········································DFN(PLP)1216-6F,

) This is an approximate value, because output current depending on conditions and external parts.

∗

DFN1616-6B, SOT-23-5

× 1.6mm DFN(PLP)1216-6B package is also

UVLO

)

(t

start

············· Typ. 2.0V

)

························ Typ. 0.15ms

Delay time for protection Typ. 1.5ms

“L”: forced PWM
(RP504N does not have MODE pin)

BLOCK DIAGRAM TYPICAL APPLICATION

Vref

Soft Start

RP504L/K

Slope

Com

ensation

OSC

PWM
Control

PVIN

Current

Feedback

Current

Protection

1

∗

Switching

Control

UVLO

LX

V

OUT

IN

V

Chip

CE

Enable

MODE

GND

*1) MODE="H": PWM/VFM auto switching、MODE="L": forced PWM

Blue Line : only RP504Kxx1D, RP504Lxx1D

L : MIPSZ2520D2R2、MIPS2520D2R2 (FDK)、

MLP2520S2R2M、VLS252010T-2R2M (TDK)

CKP2520-2R2M (TAIYO YUDEN)

IN

C

: 2.2μF: C1608JB0J225K (TDK)、

2.2μF×2: C1005JB0J225K (TDK)、JMK105BJ225MV (TAIYO YUDEN)

4.7μF: C1005X5R0J475M (TDK)、JMK105BJ475MV (TAIYO YUDEN)

C

OUT : C1608JB0J475K (TDK)、GRM155B30J475KE18 (MURATA)

VIN

C

IN

2.2μF

RP504L/K

VIN

CE

V

GND

MODE

LX

OUT

SELECTION GUIDES

Halogen Free

.xx.

: Specify the output voltage within the range of

0.8V (.08.) to 3.3V (.33.) in 0.1V steps.

Package

Q'ty per Reel

DFN(PLP)1216-6F 5,000 pcs

DFN1616-6B 5,000 pcs

SOT-23-5 3,000 pcs

Part No.

RP504L .xx1∗-E2
RP504K .xx1∗ -TR
RP504N .xx1$ -TR-FE

$ :

.

:

Select from (.A.) With MODE pin, without auto-discharge function,

.∗

(.D.) With MODE pin, with auto-discharge function,
Select from (.B.) PWM/VFM auto switching, without auto-discharge function,
(.C.) forced PWM, without auto-discharge function,

PACKAGES (Top View) TYPICAL CHARACTERISTIC

DFN(PLP)1216-6F DFN1616-6B SOT-23-5

6

3 4 2 5 1

1 VIN
2 MODE
3 CE
4 VOUT
5 GND
6 LX

) The tab is substrate level (GND).

∗

6 5 4

1 2 3

1 CE
2 MODE
3 VIN
4 LX
5 GND
6 VOUT

∗

5 4

1 3

2

1 VOUT
2 GND
3 LX
4 VIN
5 CE

RP504x (VOUT=3.3V) Efficiency vs. Output Current

100

VIN=4.3V, V

90

MODE

VIN=5.0V, V

=0V

80
70
60
50
40

Efficiency (%)

30
20
10

0

0.01 0.1 1 10 100 1000
Output Current I

OUT

VIN=V

(mA)

2.2μH

MODE

VIN=V

L

=0V

MODE

MODE

=3.6V

V

=4.3V

OUT

C

4.7μF

OUT

APPLICATIONS

• Power source for battery-powered equipment

• Power source for hand-held communication equipment, cameras, and VCRs

• Power source for compact HDD

No.EK-259-120326 Step-down DC/DC Converter

RP504x Series Step-down DC/DC Converter

600mA PWM/VFM Step-down DC/DC Converter with Synchronous Rectifier

RP50x Series 600mA
Step-down DC/DC Converter Comparison

Control

Output Current *1 600mA 600mA 600mA 600mA

Supply Current（PWM Mode）

Supply Current（VFM Mode）

RP504x Series RP500x Series RP502x Series RP503x Series

PWM/VFM auto switching /

Forced PWM

（

It can be switched by MODE pin）

PWM/VFM auto switching /

Fixed PWM

PWM/VFM auto switching /

Fixed PWM

PWM/VFM auto switching

Typ. 400μA Typ. 400μA Typ. 750μA

Typ. 25μA Typ. 100μA Typ. 180μA Typ. 20μA

-

Supply Current（Standby）

Max. 5μA

Max. 5μA

Max. 5μA Max. 5μA

Input Voltage Range 2.3V to 5.5V 2.55V to 5.5V 2.5V to 5.5V 2.5V to 5.5V
Output Voltage Range 0.8V to 3.3V 1.1V to 3.3V 0.8V to 3.3V 0.8V to 2.5V
Oscillator Frequency Typ. 2.25MHz Typ. 1.2MHz Typ. 3.3MHz Typ. 2MHz

Output Voltage Accuracy ±1.5% ±1.5% ±1.5% ±1.5%

Oscillator Maximum
Duty Cycle

Min.100% Min.100% Min.100% Min.100%

UVLO Detect Voltage Typ. 2.0V Typ. 2.2V Typ. 2.2V Typ. 2.2V
Soft-start Time Typ. 0.15ms Typ. 0.12ms Typ. 0.12ms Typ. 0.15ms
Latch Protection Circuit

（Protection Delay Time）

Typ. 1.5ms Typ. 1.5ms Typ. 1.5ms Typ. 1.5ms

Coil-current Limit Circuit Typ. 900mA Typ. 900mA Typ. 900mA Typ. 800mA

2

3

WLCSP-6-P2*

DFN1616-6*

SOT-23-5*

Package

DFN(PLP)1212-6F

DFN1616-6B

SOT-23-5*

4

WLCSP-6-P2*2

DFN1616-6*

3

DFN(PLP)1820-6

WLCSP-6-P2*

DFN1616-6*

SOT-23-6W

DFN Package

A Version

With MODE pin、

without auto-discharge function

D Version

With MODE pin、

Version

with auto-discharge function

SOT Package

B Version

PWM/VFM auto switching,

without auto-discharge function

C Version

Fixed PWM、

*1) This is an approximate value, because output current depending on conditions and external parts.
*2) RP500Z, RP502Z, and RP503Z are pin-compatible *3) RP500L, RP502L, and RP503L are pin-compatible *4) RP503N and RP504N are pin-compatible

without auto-discharge function

without auto-discharge function

without auto-discharge function

（

1 Version

PWM/VFM auto switching,

2 Version

Fixed PWM、

3 Version

PWM/VFM auto switching,

with auto-discharge function

except for the DFN package

4 Version

Fixed PWM、

with auto-discharge function

1 Version

PWM/VFM auto switching,

without auto-discharge function

2 Version

Fixed PWM、

without auto-discharge function

3 Version

PWM/VFM auto switching,

with auto-discharge function

）

Version

Fixed PWM、

with auto-discharge function

1 Version

PWM/VFM auto switching,

without auto-discharge function

4

2 Version

PWM/VFM auto switching,

with auto-discharge function

2

3

4

The currently available information as of March 2012 is provided in this New Product News.

EK-259-120326