LTC3558
4
3558f
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Logic (HPWR, SUSP, CHRG, EN1, EN2, MODE)
VIL Input Low Voltage HPWR, SUSP, MODE, EN1, EN2 Pins 0.4 V
VIH Input High Voltage HPWR, SUSP, MODE, EN1, EN2 Pins 1.2 V
RDN Logic Pin Pull-Down Resistance HPWR, SUSP Pins l1.9 4 6.3 MΩ
VCHRG CHRG Pin Output Low Voltage ICHRG = 5mA 100 250 mV
ICHRG CHRG Pin Input Current BAT = 4.5V, VCHRG = 5V 0 1 µA
Buck Switching Regulator
PVIN1 Input Supply Voltage l2.7 4.2 V
IPVIN1 Pulse Skip Input Current
Burst Mode Current
Shutdown Current
Supply Current in UVLO
FB1 = 0.85V, MODE = 0 (Note 6)
FB1 = 0.85V, MODE = 1 (Note 6)
EN1 = 0
PVIN1 = PVIN2 = 2V
l
220
35
0
4
400
50
2
8
µA
µA
µA
µA
PVIN1 UVLO PVIN1 Falling
PVIN1 Rising
l
l
2.30 2.45
2.55 2.70
V
V
fOSC Switching Frequency MODE = 0 1.91 2.25 2.59 MHz
ILIMSW1 Peak PMOS Current Limit 550 800 1050 mA
VFB1 Feedback Voltage MODE = 0 l780 800 820 mV
IFB1 FB Input Current FB1 = 0.85V –50 50 nA
DMAX1 Maximum Duty Cycle FB1 = 0V l100 %
RPMOS1 RDS(ON) of PMOS ISW1 = 100mA 0.65 Ω
RNMOS1 RDS(ON) of NMOS ISW1 = –100mA 0.75 Ω
RSW1(PD) SW Pull-Down in Shutdown 13 kΩ
Buck-Boost Switching Regulator
PVIN2 Input Supply Voltage l2.7 4.2 V
IPVIN2 PWM Input Current
Burst Mode Input Current
Shutdown Current
Supply Current in UVLO
MODE = 0, IOUT = 0A, FB2 = 0.85V (Note 6)
MODE = 1, IOUT = 0A, FB2 = 0.85V (Note 6)
EN2 = 0, IOUT = 0A
PVIN1 = PVIN2 = 2V
220
20
0
4
400
30
1
8
µA
µA
µA
µA
PVIN2 UVLO PVIN2 Falling
PVIN2 Rising
l
l
2.30 2.45
2.55 2.70
V
V
VOUT2(LOW) Minimum Regulated Buck-Boost VOUT 2.65 2.75 V
VOUT2(HIGH) Maximum Regulated Buck-Boost VOUT 5.45 5.60 V
ILIMF2 Forward Current Limit (Switch A) MODE = 0 l580 700 820 mA
IPEAK2(BURST) Forward Current Limit (Switch A) MODE = 1 l180 250 320 mA
ILIMR2 Reverse Current Limit (Switch D) MODE = 0 l325 450 575 mA
IZERO2(BURST) Reverse Current Limit (Switch D) MODE = 1 l–35 0 35 mA
IMAX2(BURST) Maximum Deliverable Output Current
in Burst Mode Operation
2.7V < PVIN2 < 4.2V
2.75V < VOUT2 < 5.5V
50 mA
VFB2 Feedback Servo Voltage l780 800 820 mV
IFB2 FB2 Input Current FB2 = 0.85V –50 50 nA
fOSC Switching Frequency MODE = 0 1.91 2.25 2.59 MHz
ELECTRICAL CHARACTERISTICS
The ldenotes specifications that apply over the full operating temperature
range, otherwise specifications are at TA = 25°C. VCC = 5V, BAT = PVIN1 = PVIN2 = 3.6V, RPROG = 1.74k, unless otherwise noted.
