LTC3554-3_15 Datasheet, PDF (4/36 Pages) Linear Technology – Micropower USB Power Manager with Li-Ion Charger and Two Step-Down Regulators

LTC3554/LTC3554-1/
LTC3554-2/LTC3554-3
POWER MANAGER Electrical Characteristics The l denotes specifications that
apply over the full operating junction temperature range, otherwise specifications are at T_A = 25°C (Note 2), V_BUS = 5V, V_BAT = 3.8V,
HPWR = SUSP = PWR_ON1 = PWR_ON2 = 0V, R_PROG = 1.87k, STBY = High, unless otherwise noted.
SYMBOL PARAMETER
CONDITIONS
MIN TYP MAX UNITS
V_DIS
NTC Disable Threshold Voltage
Falling NTC Voltage
Hysteresis
l 1.2
1.7
50
2.2
%V_BUS
mV
I_NTC
NTC Leakage Current
Ideal Diode
V_NTC = V_BUS = 5V
–50
50
nA
V_FWD
Forward Voltage Detection
R_DROPOUT Diode On-Resistance, Dropout
I_MAX
Diode Current Limit
Logic Inputs (HPWR, SUSP)
(Note 12)
I_OUT = 200mA, V_BUS = 0V
(Note 7)
15
mV
240
mΩ
1
A
V_IL
Input Low Voltage
V_IH
Input High Voltage
R_PD
Internal Pull-Down Resistance
Logic Output (CHRG)
0.4
V
1.2
V
4
MΩ
V_OL
I_CHRG
Output Low Voltage
Output Hi-Z Leakage Current
I_CHRG = 5mA
V_BAT = 4.5V, V_CHRG = 5V
65
250
mV
0
1
µA
S witching Regulator Ele ctrical Characteristics The l denotes
specifications that apply over the full operating junction temperature range, otherwise specifications are at T_A = 25°C (Note 2).
V_OUT = BVIN = 3.8V, PWR_ON1 = PWR_ON2 = 0V, unless otherwise noted.
SYMBOL PARAMETER
CONDITIONS
MIN TYP MAX UNITS
BVIN
Input Supply Voltage
(Note 9)
l 2.7
5.5
V
V_OUT UVLO V_OUT Falling
V_OUT Rising
BVIN Connected to V_OUT Through Low
2.5
2.6
V
Impedance. V_OUT UVLO Disables the Switching
2.8
2.9
V
Regulators.
f_OSC
Oscillator Frequency
FSEL High
FSEL Low
1.91 2.25 2.59
MHz
0.955 1.125 1.295
MHz
I_FB1
FB1 Input Current (Note 8)
I_FB2
FB2 Input Current (Note 8)
R_{SW1_PD} SW1 Pull-Down in Shutdown
R_{SW2_PD} SW2 Pull-Down in Shutdown
Logic Input Pins (FSEL, STBY)
PWR_ON1 = 0V
PWR_ON2 = 0V
–0.05
–0.05
0.05
µA
0.05
µA
10
kΩ
10
kΩ
Input High Voltage
1.2
V
Input Low Voltage
0.4
V
Input Current
–1
1
µA
Switching Regulator 1 in Normal Operation (STBY Low)
I_LIM1
Peak PMOS Current Limit
V_FB1
Regulated Feedback Voltage
D1
Max Duty Cycle
PWR_ON1 = 3.8V (Note 7)
PWR_ON1 = 3.8V
300 450
600
mA
l 780
800
820
mV
100
%
R_P1
R_DS(ON) of PMOS
R_N1
R_DS(ON) of NMOS
Switching Regulator 1 in Standby Mode (STBY High)
I_SW1 = 100mA
I_SW1 = –100mA
1.1
Ω
0.7
Ω
V_{FB1_LOW}
I_{SHORT1_SB}
V_{DROP1_SB}
Feedback Voltage Threshold
Short-Circuit Current
Standby Mode Dropout Voltage
PWR_ON1 = 3.8V, V_FB1 Falling
l 770
800
820
mV
10
21
50
mA
PWR_ON1 = 2.9V, I_SW1 = 5mA, V_FB1 = 0.77V,
V_OUT = 2.9V, BVIN = 2.9V
25
60
mV
4
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