TC1303B Datasheet, PDF (10/30 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.
2.20
2.15
SHDN1 = V_IN2
SHDN2 = A_GND
2.10
2.05
2.00
1.95
1.90
2.7 3.1 3.5 3.9 4.3 4.7 5.1 5.5
Input Voltage (V)
FIGURE 2-13:
V_OUT1 Switching Frequency
vs. Input Voltage.
0.6
0.55
0.5
T_A = 25 °C
SHDN1 = V_IN2
SHDN2 = A_GND
0.45
0.4
N-Channel
0.35
P-Channel
0.3
3.3 3.5 3.7 3.9 4.1 4.3 4.5 4.7 4.9 5.1 5.3 5.5
Input Voltage (V)
FIGURE 2-16:
V_OUT1 Switch Resistance
vs. Input Voltage.
2.00
1.98
1.96
1.94
1.92
1.90
SHDN1 = V_IN2
SHDN2 = A_GND
Ambient Temperature (°C)
FIGURE 2-14:
V_OUT1 Switching Frequency
vs. Ambient Temperature.
0.65
0.6
V_IN1 = 3.6V
SHDN1 = V_IN2
SHDN2 = A_GND
0.55
P-Channel
0.5
N-Channel
0.45
0.4
0.35
0.3
-40 -25 -10 5 20 35 50 65 80 95 110 125
Ambient Temperature (°C)
FIGURE 2-17:
Buck Regulator Switch
Resistance vs. Ambient Temperature.
0.820
0.815
0.810
0.805
0.800
0.795
0.790
V_IN1 = 3.6V
SHDN1 = V_IN2
SHDN2 = A_GND
Ambient Temperature (°C)
FIGURE 2-15:
V_OUT1 Adjustable Feedback
Voltage vs. Ambient Temperature.
0.4
0.35
SHDN1 = V_IN2
SHDN2 = A_GND
0.3
0.25
0.2
0.15
0.1
V_OUT1 = 3.3V
I_OUT1 = 500 mA
Ambient Temperature (°C)
FIGURE 2-18:
V_OUT1 Dropout Voltage vs.
Ambient Temperature.
DS21949A-page 10
2005 Microchip Technology Inc.