LTC3576 Datasheet, PDF (7/48 Pages) Linear Technology – Switching Power Manager with USB On-the-Go + Triple Step-Down DC/DCs

LTC3576/LTC3576-1
TYPICAL PERFORMANCE CHARACTERISTICS T_A = 25°C unless otherwise specified.
Ideal Diode V-I Characteristics
1.0
INTERNAL IDEAL DIODE
WITH SUPPLEMENTAL
0.8
EXTERNAL VISHAY
Si2333 PMOS
0.6
INTERNAL IDEAL
DIODE ONLY
0.4
0.2
0
0
V_BUS = 5V
0.04 0.08 0.12 0.16 0.20
FORWARD VOLTAGE (V)
3576 G01
USB Limited Load Current vs Battery
Voltage (Battery Charger Disabled)
900
V_BUS = 5V
800
5x MODE
700
600
500
400
300
200
100
0
2.7 3.0 3.3 3.6 3.9 4.2
BATTERY VOLTAGE (V)
3576 G04
Ideal Diode Resistance
vs Battery Voltage
0.25
0.20
INTERNAL IDEAL
DIODE
0.15
0.10
INTERNAL IDEAL DIODE
WITH SUPPLEMENTAL
0.05
EXTERNAL VISHAY
Si2333 PMOS
0
2.7
3.0
3.3
3.6
3.9
4.2
BATTERY VOLTAGE (V)
3576 G02
Battery and V_BUS Currents
vs Load Current
750
V_BUS CURRENT
500
250
BATTERY CURRENT
(CHARGING)
0
V_BUS = 5V
BAT = 3.8V
–250 _{5x MODE}
R_CLPROG = 3.01k BATTERY CURRENT
R_PROG = 1k
(DISCHARGING)
–500
0 100 200 300 400 500 600 700 800 900 1000
LOAD CURRENT (mA)
3576 G05
PowerPath Switching Regulator
Transient Response
V_OUT
50mV/DIV
AC COUPLED
I_VOUT
500mA/DIV
0mA
V_BUS = 5V
V_OUT = 3.65V
CHARGER OFF
10x MODE
20μs/DIV
3576 G07
PowerPath Switching Regulator
Efficiency vs Load Current
100
90
1x MODE
80
70
5x, 10x MODE
60
50
40
30
10
100
LOAD CURRENT (mA)
1000
3576 G08
V_OUT Voltage vs Load Current
(Battery Charger Disabled)
4.50
BAT = 4V
4.25
4.00
BAT = 3.4V
3.75
3.50
3.25
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
LOAD CURRENT (A)
3576 G03
Battery Charge Current vs
Temperature
600
R_PROG = 2k
500
400
THERMAL REGULATION
300
200
100
0
–40 –20 0 20 40 60 80 100 120
TEMPERATURE (°C)
3576 G06
Battery Charging Efficiency vs
Battery Voltage with No External
Load (P_BAT/P_VBUS)
95
R_CLPROG = 3.01k
90 R_PROG = 1k
85
1x MODE
80
75
70
65
5x MODE
60
55
50
2.7
3.0 3.3 3.6 3.9 4.2
BATTERY VOLTAGE (V)
3576 G09
3576f
7