RH5RH301A Datasheet, PDF (6/29 Pages) RICOH electronics devices division – PWM STEP-UP DC/DC CONVERTER

RH5RH
ELECTRICAL CHARACTERISTICS
• RH5RH301A
Symbol
VOUT
VIN
Vstart
Vhold
Item
Output Voltage
Input Voltage
Start-up Voltage
Hold-on Voltage
Conditions
IOUT=1mA,VIN : 0→2V
IOUT=1mA,VIN : 2→0V
MIN.
TYP. MAX.
VOUT=3.0V
Unit Note
2.925 3.000 3.075 V
8
V
0.8 0.9 V
0.7
V
IDD1
Supply Current 1
To be measured at OUT Pin
(excluding Switching Current)
15 25 µA
IDD2
Supply Current 2
To be measured at OUT Pin
(excluding Switching Current)
VIN=3.5V
2
5
µA
ILX
ILXleak
fosc
Lx Switching Current
Lx Leakage Current
Oscillator Frequency
VLX=0.4V
VLX=6V,VIN=3.5V
60
mA
0.5 µA
40
50 60 kHz
Maxdty
η
Oscillator Maximum Duty
Cycle
Efficiency
on (VLX “L” ) side
70
80 90
%
70
85
%
tstart
Soft-Start Time
VLXlim
VLX Voltage Limit
Time required for the rising _0.5
2.0
of VOUT up to 3V.
ms Note1
Lx Switch ON
0.65 0.8 1.0 V Note2
Unless otherwise provided, VIN=1.8V, VSS=0V, IOUT=10mA, Topt=25˚C, and use External Circuit of Typical
Application (FIG. 1).
(Note 1) Soft-Start Circuit is operated in the following sequence :
(1) VIN is applied.
(2) The voltage (Vref) of the reference voltage unit is maintained at 0V for about 200µs after the application of VIN.
(3) The output of Error Amp. is raised to “H” level during the maintenance of the voltage (Vref) of the reference voltage unit.
(4) After the rise of Vref, the output of Internal Error Amp. is gradually decreased to an appropriate value by the function of Internal Phase
Compensation Circuit, and the Output Voltage is gradually increased in accordance with the gradual decrease of the output of Internal Error
Amp.
(Note 2) ILX is gradually increased after Lx Switch is turned ON. In accordance with the increase of ILX, VLX is also increased. When VLX reaches VLXlim,
Lx Switch is turned OFF by an Lx Switch Protection Circuit.
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