TC1303B Datasheet, PDF (13/30 Pages) Microchip Technology – 500 mA Synchronous Buck Regulator, + 300 mA LDO with Power-Good Output

TC1303B
Note: Unless otherwise indicated, V_IN1 = V_IN2 = SHDN1,2 = 3.6V, C_OUT1 = C_IN = 4.7 µF, C_OUT2 = 1 µF, L = 4.7 µH,
V_OUT1 (ADJ) = 1.8V, T_A = +25°C. Boldface specifications apply over the T_A range of -40°C to +85°C. T_A = +25°C. Adjustable or fixed
output voltage options can be used to generate the Typical Performance Characteristics.
0.02
0.018
V_IN = 3.6V
0.016
0.014
0.012
0.01
I_OL = 1.2 mA
SHDN1 = V_IN2
SHDN2 = V_IN2
Ambient Temperature (°C)
FIGURE 2-31:
PG Output Voltage Level
Low vs. Ambient Temperature.
10
SHDN1 = A_GND
SHDN2 = V_IN2
1
0.1
V_IN = 3.6V
V_OUT2 = 2.5V
I_OUT2 = 50 mA
0.01
0.01 0.1
1
10 100
Frequency (kHz)
1000 10000
FIGURE 2-34:
V_OUT2 Noise vs. Frequency.
3.0
V_OUT2 = 2.8V
2.5
V_OUT2 = 2.5V
2.0
1.5
V_OUT2 = 1.5V
1.0
0.5 ^VIN ^{= 3.6V}
I_OH = 500 µA
0.0
-40 -25 -10 5
SHDN1 = V_IN2
SHDN2 = V_IN2
20 35 50 65 80 95 110 125
Ambient Temperature (°C)
FIGURE 2-32:
PG Output Voltage Level
High vs. Ambient Temperature.
FIGURE 2-35:
vs. Time.
V_OUT1 Load Step Response
0
SHDN1 = GND
-10 _{VOUT2 = 1.5V}
-20 ^{IOUT2 = 30 mA}
C_IN = 0 µF
-30
-40
-50
-60
-70
-80
0.01
0.1
1
C_OUT2 = 1.0 µF
C_OUT2 = 4.7 µF
10
100 1000
Frequency (kHz)
FIGURE 2-33:
V_OUT2 Power Supply Ripple
Rejection vs. Frequency.
FIGURE 2-36:
vs. Time.
V_OUT2 Load Step Response
© 2005 Microchip Technology Inc.
DS21949A-page 13