0
10
20
30
40
50
60
70
80
90
100
0.001 0.01 0.1 1 10 100
Efficiency [%]
I
OUT
[mA]
Vin=2.3V
Vin=3.6V
Vin=5.5V
0.3 µA I
Q
Ultra-low Quiescent Current
100 mA Buck DC/DC Converter
VFM (f
SW
up to 1 MHz) control achieves 0.3 μA ultra-low operating quiescent current.
The wide range of V
IN
from 2.0 V to 5.5 V allows operation from coin cell to USB port.
Total mount area including C
IN
, C
OUT
, and inductor is 8.３ mm
2
.
Selectable packages including WLCSP, DFN, and SOT. 0.4 mm-thickness WLCSP package adaptable to IC cards.
No. EV-502-210210
1
Output Current: 100 mA
Output Voltage Range: 1.0 V to 4.0 V ( in 0.1 V step)
Output Voltage Accuracy: ±1.5% (V
SET
≥ 1.2 V), ±18 mV (V
SET
< 1.2 V)
Built-in Driver On-resistance (V
IN
= 3.6 V):
Typ. PMOS 0.15 Ω, NMOS 0.15 Ω (RP511Z)
Standby Current: Typ. 0.01 µA
KEY SPECIFICATIONS
APPLICATIONS
PACKAGE / OPTIONAL FUNCTIONS
Wearable equipment such as SmartWatch, SmartBand, and health
monitoring
Li-ion battery-used equipment, Coin cell-used equipment
Low power RF such as Bluetooth® Low Energy, Zigbee, WiSun, and
ANT
Low power CPU, memory, sensor devices, and energy harvesting
V
IN
CE
LX
VOUT
GND
V
IN
C
IN
C
OUT
V
OUT
L
RP511x
TYPICAL APPLICATION CIRCUIT
L：2.２μH 、 C
OUT
：22μF
V
SET
= 1.8 V
TYPICAL CHARACTERISTICS
$ Auto-discharge Function V
SET
(xx)
A No
10 to 40
(1.0 V to 4.0 V）
B Yes
xx: Set Output Voltage (V
SET
)、$: Version
RP511Zxx1$
WLCSP-8-P1
1.45 x 1.48 x 0.36 (mm)
RP511Hxx1$
SOT-89-5
4.5 x 4.35 x 1.5 (mm)
RP511Kxx1$
DFN(PLP)2527-10
2.7 x 2.5 x 0.6 (mm)
0
20
40
60
80
100
0.001 0.01 0.1 1 10 100 1000
Efficiency [%]
Output Current [mA]
V
IN
= 3.6 V, V
OUT
= 1.8 V
Longer battery life by reducing standby current
2
General Issue
Extending battery life by reducing standby power as much as possible since standby time is much longer than system
operating time.
Downsizing batteries to design a easy-carrying mobile product.
RICOH’s RP511x provide longer battery life by reducing reactive power at standby time with low consumption current of
0.3 μA and the total power consumption.
RICOH’s RP511x are suitable for smaller batteries due to the high power efficiency.
Ricoh’s Solution
Intermittent time = 60 s
RP110x: LDO (Iss = 1.0 μA) RP509x: DCDC (Iss = 15 μA) RP511x: DCDC (Iss = 0.3 μA)
Active (ON) Standby Active (ON) Standby Active (ON) Standby
Time 0.01 s 59.99 s 0.01 s 59.99 s 0.01 s 59.99 s
RF, BLE 5 mA 6.0 μA 4.93 mA 19.9 μA 4.93 mA 5.4 μA
Memory + Sensor 2 mA 3.0 μA 1.12 mA 16.7 μA 1.10 mA 1.5 μA
MPU 5 mA 6.0 μA 1.94 mA 16.7 μA 1.92 mA 2.4 μA
TOTAL 12 mA 15.0 μA 7.99 mA 53.3 μA 7.74 mA 9.3 μA
Average 17.0 μA 54.5 μA 10.6 μA
Battery (50 mAh)
Operating Time
122 day 38 days 196 days
Battery life is more than 5 times longer!
As for low supply products, the intermittent operation reduces the power
consumption and prolongs battery life as shown in the figure below.
During the operation, standby time becomes much longer than Active (On) time.
Here is an example when the ratio of standby time to Active (On) time is 5999: 1.
Intermittent operation
0.3 µA I
Q
Ultra-low Quiescent Current
100 mA Buck DC/DC Converter
Active(On) Current
Standby time
Standby Current
On time
0A : OFF
Application example
Replaced RP110x: LDO (Iss = 1.0 μA) and RP509x: DC/DC
(Iss = 15 μA) with RP511x: DC/DC (Iss = 0.3 μA)
The value in () is each
current when using LDO.
RP511x: DCDC (Iss = 0.3 µA)
RP509x: DCDC (Iss = 15 µA)
RP110x: LDO (Iss = 1.0 µA)
Battery
RP511x
RP511x
RP511x
3.3 V
1.8 V
1.2 V
Li 1 Cell
3.0 V ~ 4.5 V
RF, BLE
(5 mA/5 µA)
Memory, Sensor
(2 mA/2 µA)
MPU
(5 mA/5 µA)
No. EV-502-210210
VFM (f
SW
up to 1 MHz) control achieves 0.3 μA ultra-low operating quiescent current.