RH5RH
• RH5RH501A
VOUT=5.0V
Symbol
VOUT
VIN
Item
Output Voltage
Input Voltage
Conditions
MIN.
TYP. MAX.
Unit
V
Note
4.875 5.000 5.125
8
V
Vstart
Vhold
Start-up Voltage
Hold-on Voltage
Iout=1mA,Vin:0→2V
Iout=1mA,Vin:2→0V
0.8
0.9
V
0.7
V
To be measured at OUT Pin
(excluding Switching Current)
IDD1
Supply Current 1
30
2
45
5
µA
µA
To be measured at OUT Pin
(excluding Switching Current)
VIN=5.5V
IDD2
Supply Current 2
ILX
ILXleak
fosc
Lx Switching Current
Lx Leakage Current
Oscillator Frequency
VLX=0.4V
80
mA
µA
VLX=6V,VIN=5.5V
0.5
60
40
70
50
80
kHz
Oscillator Maximum Duty
Cycle
Maxdty
η
on (VLX “L” ) side
90
%
Efficiency
70
85
%
Time required for the rising
of VOUT up to 5V.
tstart
Soft-Start Time
2.0
0.5
ms
Note1
Note2
VLXlim
VLX Voltage Limit
Lx Switch ON
0.65
0.8
1.0
V
Unless otherwise provided, VIN=3V, 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.
6
RICOH [ RICOH ELECTRONICS DEVICES DIVISION ]
