RICOH RN5T653 Technical data
Charge pump for White LED
RN5T653
Development Specifications
Rev. 1.8
2009/05/12
RICOH COMPANY, LTD.
Electronic Devices Company
This specification is subject to change without notice.
RN5T653 CHARGE PUMP FOR WHITE LED
Table of Contents
1.
Outline........................................................................................................................................................................2
2. Feature .......................................................................................................................................................................2
3. Ordering Information ...............................................................................................................................................2
4. Pin Configuration......................................................................................................................................................3
5. Typical Application Circuit ......................................................................................................................................4
6. Pin Description ..........................................................................................................................................................5
7. Functional Blocks......................................................................................................................................................6
7.1 Regulators ........................................................................................................................................................... 6
7.1.1 Linear Regulators Table (Ordering Table) ................................................................................................ 6
7.2 LDO1/2 Electrical Characteristics ......................................................................................................................7
7.3 Charge Pump.......................................................................................................................................................8
7.3.1 Block Diagram ..........................................................................................................................................8
7.3.2 Backlight LED........................................................................................................................................... 9
7.3.3 Protection Circuit .................................................................................................................................... 10
7.3.4 Unused DIN_ pin ....................................................................................................................................10
7.3.5 Soft-start.................................................................................................................................................. 10
7.3.6 Luminance Control.................................................................................................................................. 11
7.3.7 PWM Adjustment with Time Control .....................................................................................................12
7.3.8 Charge Pump Electrical Characteristics .................................................................................................. 16
7.4 UVLO (Under Voltage Lock Out)....................................................................................................................16
7.5 Thermal Shut-down Circuit ..............................................................................................................................17
7.5.1 Thermal Shut-down Electrical Characteristics........................................................................................ 17
8. Electrical Characteristics........................................................................................................................................18
8.1 Absolute Maximum Ratings .............................................................................................................................18
8.2 Recommendation of Operation Conditions.......................................................................................................18
8.3 DC Characteristics ............................................................................................................................................18
8.4 General Characteristics .....................................................................................................................................18
9. Package Information...............................................................................................................................................19
©2009 Rev. 1.8 Page 1
RN5T653 CHARGE PUMP FOR WHITE LED
1. Outline
RN5T653 contains a constant frequency charge pump, which is optimized for White LED application. Output
enable/disable, LEDs current and LDOs output voltage are individually controllable through single wire serial pulse I/F.
2. Feature
z White LED Charge Pump
9 Current capability: Up to 80mA
9 1x/1.5x switchable charge pump mode
9 Power up four LEDs for backlight: Up to 20mA/LED
9 Luminance control through 16-logarithmic scale
9 Soft-start
z Power Supply Function
9 LDO (150mA) × 2 (ON/OFF through single wire serial pulse I/F)
9 Over current protection (All Regulators) and thermal shut-down
z Others
9 UVLO
9 Short-circuit protection
z Package
9 20pin QFN package (Body size: 3.0 x 3.0mm, Pin pitch 0.4mm)
z Process
9 CMOS process
3. Ordering Information
RN5T653□ -- □ : S, T, U, V.
LDO1 LDO2 LED Luminance
RN5T653S 1.8V 2.8V Type-A
RN5T653T 1.5V 2.8V Type-A
RN5T653U 1.8V 2.8V Type-B
RN5T653V 1.5V 2.8V Type-B
LED Luminance
LED Luminance
Type-A Type-B
OFF⇒ON(20.3mA)
19.8mA 19.8mA 1
18.8mA 18.8mA 2
17.8mA 17.8mA 3
16.8mA 16.8mA 4
16.0mA 15.5mA 5
12.8mA 13.0mA 6
10.3mA 10.0mA 7
9.0mA 9.0mA 8
8.0mA 6.8mA 9
6.3mA 5.0mA 10
5.0mA 3.3mA 11
4.5mA 2.0mA 12
4.0mA 1.0mA 13
3.3mA 0.5mA 14
0% 15
Count Value
0
©2009 Rev. 1.8 Page 2
RN5T653 CHARGE PUMP FOR WHITE LED
4. Pin Configuration
DIN2
DIN3
DIN4
C2P
VOUT
DIN1
GND1
19
20
1
2
3
TOP VIEW
4
5
6
7
C1P
C1M
GND2
18
8
VREF
17
9
C2M
LDOUT1
16
10
GNDP
15
14
13
12
11
VCCVIN2
LDOUT2
LEDCTL
LDO2CTL
LDO1CTL
VCCVIN1
Fig 4-1 Pin Configuration
©2009 Rev. 1.8 Page 3
RN5T653 CHARGE PUMP FOR WHITE LED
5. Typical Application Circuit
1.0uF
1.0uF
1.0uF
VCCVIN2
VREF
LDOUT1
LDOUT2
GND2
LDO1CTL
LDO2CTL
LEDCTL
VREF
LDO1
Charge Pump
@80mA
LDO2
Digital
Thermal Shut-down
UVLO
CC Driver (Main)
Fig 5-1 Typical Application Circuit
VCCVIN1
C2P
1uF
C2M
C1P
1uF
C1M
VOUT
2.2uF
PGND1
DIN1
@20mA
DIN2
@20mA
DIN3
@20mA
DIN4
@20mA
GND1
4.7uF
GND
GND
©2009 Rev. 1.8 Page 4
RN5T653 CHARGE PUMP FOR WHITE LED
6. Pin Description
No. Name I/O Description Notes
1
2
3
4
5
6
7
8 VCCVIN1 PWR
9
10
11
12
13
14
15
16
17
18
19
20
DIN2
DIN3
DIN4
C2P
VOUT
C1P
C1M
C2M
GNDP
LDO1CTL
LDO2CTL
LEDCTL
LDOUT2
VCCVIN2
LDOUT1
VREF
GND2
GND1 GND
DIN1
O LED driver current control output
O LED driver current control output
O LED driver current control output
- Charge pump boost capacitor connection
O LED driver voltage output
- Charge pump boost capacitor connection
- Charge pump boost capacitor connection
- Charge pump boost capacitor connection
GND Power Ground 1
I Input of LDO1 for ON/OFF.
I Input of LDO2 for ON/OFF.
I Input of LED for ON/OFF and current setting.
O Output of LDO2
PWR Power supply for LDO, UVLO, VREF and TSHUT.
O Output of LDO1.
O Output of voltage reference. Please do not connect anything. No load
GND Ground2
O LED driver current control output
Power supply for charge pump. VCCVIN1 is high impedance
during shut-down.
Ground1
Table 6-1 Pin Description
©2009 Rev. 1.8 Page 5
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