LTC3455 Datasheet, PDF (3/24 Pages) Linear Technology – Dual DC/DC Converter with USB Power Manager and Li-Ion Battery Charger

LTC3455
ELECTRICAL CHARACTERISTICS The q denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T_A = 25°C. V_BAT = 3.6V, V_MAX = 3.6V, V_PWRON = 2V, V_ON is open, V_ON2 = 0V,
V_USB = 0V, V_WALLFB = 0V unless otherwise noted.
PARAMETER
Battery-V_MAX PMOS
V_MAX PMOS Switch On-Resistance
V_MAX Switch Current Limit
V_MAX Switch Current Limit at Startup
Gain Block
AI Pin Threshold Voltage
AI Pin/FB2 Pin Voltage Difference
AI Pin Input Bias Current
AO Pin Sink Current
AO Pin Voltage
Switching Regulators
FB1, FB2 Voltage
FB1, FB2 Voltage Line Regulation
FB1, FB2 Voltage Burst Mode Hysteresis
FB1, FB2 Pin Input Bias Current
Switching Frequency
PMOS Switch On-Resistance
NMOS Switch On-Resistance
PMOS Switch Current Limit
CONDITIONS
With V_MAX Rising, V_MAX = 3V, V_BAT = 3.6V
V_FB2 – V_AI
V_AI = 0.85V
V_AI = 0.6V, V_AO = 1.5V
V_AI = 0.6V, I_AO = 1mA
V_MAX = 3V to 5V
V_MODE = 2V
V_FB1 = V_FB2 = 0.85V
Both Switchers
Both Switchers
Both Switchers
Switcher 1
Switcher 2
MIN TYP MAX UNITS
0.15
Ω
2.5
4.0
A
0.4
0.9
A
q 0.784 0.805 0.826
V
–8
0
8
mV
q
±1
±25
nA
1.0
1.8
2.5
mA
0.8
1.2
V
q 0.784 0.805 0.826
V
0.01
%/V
8
mV
q
±1
±25
nA
1.2
1.5
1.8
MHz
0.35
Ω
0.45
Ω
450 600 850
mA
700 900 1200
mA
USB Power Manager
USB Undervoltage Lockout Voltage
USB Undervoltage Lockout Hysteresis
From Low to High
3.75 3.90 4.10
V
150
mV
USB Minimum Voltage to Charge Battery
USB PMOS Switch On-Resistance
USB Current Limit
USB Suspend Mode Bias Current
SUSPEND Pin Threshold
V_USB = 5V
V_USB = 5V, V_USBHP = 2V
V_USB = 5V, V_USBHP = 0V
V_USB = 5V, V_SUSPEND = 2V
4.0
V
0.5
Ω
q 440
475
500
mA
q 60
80
100
mA
4
20
µA
0.8
1.1
V
USBHP Pin Threshold
SUSPEND Pin Pulldown Current
USBHP Pin Pulldown Current
Hot Swap Output
Hot Swap PMOS Switch On-Resistance
Hot Swap PMOS Switch Current Limit
HSON Pin Threshold
HSON Pin Pulldown Current
V_SUSPEND = 0.5V
V_USBHP = 0.5V
V_HSI = 3.3V
V_HSI = 3.3V, V_HSO = 2.5V
0.8
1.1
V
2.5
µA
2.5
µA
0.9
Ω
120 160
mA
0.8
1.1
V
2.5
µA
3455f
3