R1171S151A Datasheet, PDF (23/36 Pages) RICOH electronics devices division – 2.0A/1.5A LDO REGULATOR

ESR vs. Output Current
When using these ICs, consider the following points:
R1172x
VIN
CIN
CE
VOUT
R1172xxx1B
VIN
GND
COUT
ESR
IOUT
S.A ^Spectrum
Analyzer
0.8V to 3.3V Output type: COUT=4.7µF (Kyocera CM105X5R475M06AB)
5.0V Output type
: COUT=4.7µF (Kyocera CT21X5R475K06AB)
As an output capacitor for this IC, Ceramic capacitor is recommendable. However, other low ESR type
capacitor can be used with this IC.
For your reference, noise level is tested, and if the noise level is 40µV or less than 40µV, the ESR values are
plotted as stable area. Upper limit is described in the next five graphs, or ESR vs. Output Current. (Hatched area
is the stable area.)
Measurement conditions
⋅ VIN=VOUT+1V
⋅ Frequency Band: 10Hz to 1MHz
⋅ Temperature : 25°C
R1172x081x
VIN=1.4V to 6.0V,
CIN=COUT=Ceramic 4.7µF
100
Topt=85°C
10
Topt=-40°C
1.0
R1172x081x
VIN=1.4V to 6.0V, CIN=Ceramic 4.7µF,
COUT=Ceramic 10µF
100
Topt=85°C
10
Topt=-40°C
1.0
0.1
0.1
0.01
0
200 400 600 800 1000
Load Current IOUT(mA)
0.01
0
200 400 600 800 1000
Load Current IOUT(mA)
23