TC1303A/TC1303B/TC1303C/TC1304
DS21949C-page 8
2008 Microchip Technology Inc.
Synchronous Buck Regulator (VOUT1)
Adjustable Output Voltage Range
VOUT1
0.8
—
4.5
V
Adjustable Reference Feedback
Voltage (VFB1)
VFB1
0.78
0.8
0.82
V
Feedback Input Bias Current
(IFB1)
IVFB1
—-1.5
—
nA
Output Voltage Tolerance Fixed
(VOUT1)
VOUT1
-2.5
±0.3
+2.5
%
Line Regulation (VOUT1)VLINE-REG
—
0.2
—
%/V
VIN =VR+1V to 5.5V,
ILOAD = 100 mA
Load Regulation (VOUT1)VLOAD-REG
—0.2
—
%
VIN =VR +1.5V, ILOAD = 100 mA to
Dropout Voltage VOUT1
VIN – VOUT1
—
280
—
mV
IOUT1 = 500 mA, VOUT1 =3.3V
Internal Oscillator Frequency
FOSC
1.6
2.0
2.4
MHz
Start Up Time
TSS
—0.5
—
ms
TR = 10% to 90%
RDSon P-Channel
RDSon-P
—
450
—
m
Ω
IP=100 mA
RDSon N-Channel
RDSon-N
—
450
—
m
Ω
IN=100 mA
LX Pin Leakage Current
ILX
-1.0
±0.01
1.0
μA
SHDN = 0V, VIN = 5.5V, LX = 0V,
LX = 5.5V
Positive Current Limit Threshold
+ILX(MAX)
—
700
—
mA
LDO Output (VOUT2)
Output Voltage Tolerance (VOUT2)VOUT2
-2.5
±0.3
+2.5
%
Temperature Coefficient
TCVOUT
—
25
—
ppm/°C
Line Regulation
VOUT2/
VIN
-0.2
±0.02
+0.2
%/V
(VR+1V) ≤ VIN ≤ 5.5V
Load Regulation, VOUT2 ≥ 2.5V
VOUT2/
IOUT2
-0.75
-0.08
+0.75
Load Regulation, VOUT2 < 2.5V
VOUT2/
IOUT2
-0.9
-0.18
+0.9
Dropout Voltage VOUT2 > 2.5V
VIN – VOUT2
—
137
205
300
500
mV
IOUT2 = 300 mA
Power Supply Rejection Ratio
PSRR
—
62
—
dB
f
≤ 100 Hz, IOUT1 = IOUT2 = 50 mA,
CIN = 0 F
Output Noise
eN
—
1.8
—
V/(Hz) f
≤ 1 kHz, IOUT2 =50mA,
SHDN1 =GND
DC CHARACTERISTICS (CONTINUED)
Electrical Characteristics: VIN1 =VIN2 = SHDN1,2 = 3.6V, COUT1 =CIN = 4.7 F, COUT2 =1F, L = 4.7 H, VOUT1 (ADJ) = 1.8V,
IOUT1 = 100 mA, IOUT2 = 0.1 mA TA = +25°C. Boldface specifications apply over the TA range of -40°C to +85°C.
Parameters
Sym
Min
Typ
Max
Units
Conditions
Note 1:
The Minimum VIN has to meet two conditions: VIN ≥ 2.7V and VIN ≥ VRX + VDROPOUT, VRX = VR1 or VR2.
2:
VRX is the regulator output voltage setting.
3:
TCVOUT2 = ((VOUT2max – VOUT2min) * 106)/(VOUT2 * DT).
4:
Regulation is measured at a constant junction temperature using low duty-cycle pulse testing. Load regulation is tested
over a load range from 0.1 mA to the maximum specified output current.
5:
Dropout voltage is defined as the input-to-output voltage differential at which the output voltage drops 2% below its
nominal value measured at a 1V differential.
6:
The maximum allowable power dissipation is a function of ambient temperature, the maximum allowable junction
temperature and the thermal resistance from junction to air. (i.e. TA, TJ, θJA). Exceeding the maximum allowable power
dissipation causes the device to initiate thermal shutdown.
7:
The integrated MOSFET switches have an integral diode from the LX pin to VIN, and from LX to PGND. In cases where
these diodes are forward-biased, the package power dissipation limits must be adhered to. Thermal protection is not
able to limit the junction temperature for these cases.
8:
VIN1 and VIN2 are supplied by the same input source.