MCP16321_13 Datasheet, PDF (4/34 Pages) Microchip Technology – 24V Input, 1A/2A Output, High Efficiency Synchronous Buck Regulator with Power Good Indication

MCP16321/2
DC CHARACTERISTICS (CONTINUED)
Electrical Characteristics: Unless otherwise indicated, T_A = +25°C, V_IN = 12V, V_OUT = 3.3V, I_OUT = 300 mA,
L = 4.7 µH, C_OUT = 2x22 µF, C_IN = 2x10 µF. Boldface specifications apply over the T_J range of -40°C to +125°C.
Parameters
Sym
Min
Typ
Max
Units Conditions
PFM Mode Feedback
EN Input Characteristics
V_FB-PFM
—
V_OUT + 1%
—
V
EN Input Logic High
EN Input Logic Low
EN Input Hysteresis
EN Input Leakage Current
Soft-Start Time
Switching Characteristics
V_IH
V_IL
V_EN-HYST
I_ENLK
t_SS
2.2
—
—
—
—
480
—
3.5
—
-1.5
—
4
—
V
0.8
V
—
mV
—
µA V_EN = 5V
—
µA V_EN = 0V
—
ms
Switching Frequency
f_SW
0.9
1
1.1
MHz Open Loop V_FB
Low
Maximum Duty Cycle
DC_MAX
95
97
99
% Open Loop V_FB
Low
Note 1
Minimum Duty Cycle
—
7
—
%
NMOS Low-Side
Switch On Resistance
Low-Side R_DS(ON)
—
120
—
mΩ
NMOS High-Side
Switch On Resistance
NMOS High-Side
Switch Current Limit
High-Side
—
180
R_DS(ON)
I_N(MAX)
1.4
1.8
2.4
2.8
—
mΩ
2.4
A MCP16321
3.4
A MCP16322
PG Output Characteristics
PG Low-level
Output Voltage
PG_IL
—
—
0.01
V I_PG = -0.3 mA
PG High-Level Output Leak-
age Current
I_PGLK
—
0.5
—
µA V_PG = 5V
PG Release Timer
t_PG
—
10
—
ms
V_OUT Undervoltage Threshold
V_OUT-UV
91% V_OUT 93% V_OUT 95% V_OUT
V_OUT Undervoltage
Hysteresis
V_{OUT-UV_HYST}
—
1.5% V_OUT
—
V_OUT Overvoltage
Threshold
V_OUT-OV
—
103% V_OUT
—
V_OUT Overvoltage
Hysteresis
V_{OUT-OV_HYST}
—
1% V_OUT
—
Thermal Characteristics
Thermal Shutdown
Die Temperature
T_SD
—
170
—
°C
Die Temperature
Hysteresis
T_SDHYS
—
10
—
°C
Note 1: Regulator SW pin is forced off for 240 ns every 8 cycles to ensure the BOOST cap is replenished.
DS22285A-page 4
© 2011 Microchip Technology Inc.