LTC3226_12 Datasheet, PDF (3/16 Pages) Linear Technology – 2-Cell Supercapacitor Charger

LTC3226
ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating
junction temperature range, otherwise specifications are at T_A = 25°C (Note 3). V_IN = 3.3V, V_CPO = 5V, V_OUT = 3.3V, VMID = 1/2 V_CPO
unless otherwise noted.
SYMBOL PARAMETER
CONDITIONS
MIN TYP MAX
V_IN
I_VIN(ST)
I_CPO(ST)
I_VOUT(ST)
Input Supply Range
V_IN Quiescent Current in Normal Mode
CPO Quiescent Current in Normal Mode
V_OUT Quiescent Current in Normal Mode
I_CPO(BU)
I_VOUT(BU)
CPO Quiescent Current in Backup Mode
V_OUT Quiescent Current in Backup Mode
Ideal Diode Controller
l 2.5
5.5
V_PFI > 1.2V, V_{CPO_FB} > 1.2V, V_IN < V_CPO
10
V_PFI > 1.2V, V_{CPO_FB} > 1.2V, V_IN < V_CPO
20
V_OUT = V_IN, V_PFI > 1.2V, V_{CPO_FB} > 1.2V,
5
V_IN < V_CPO
V_PFI < 1.2V, V_{LDO_FB} > 0.8V, V_CPO > V_OUT
24
V_IN = 0V, V_PFI < 1.2V, V_{LDO_FB} > 0.8V,
3
V_CPO > V_OUT
V_FWD(EDA) External Ideal Diode Forward Voltage (V_IN-V_OUT) I_VOUT = 2mA
15
V_RTO
Fast Turn-Off Voltage (V_IN-V_OUT)
V_IN Falling
–45
Fast Turn-On Voltage (V_IN-V_OUT)
V_OUT Falling
45
Charge Pump Supercapacitor Charger
V_{CPO_FB}
CPO_FB Pin Threshold for Entering Sleep Mode
CPO_FB Pin Hysteresis for Exiting Sleep Mode
l 1.18 1.21 1.24
20
I_{CPO_FB}
f_OSC
R_OL
V_PROG
I_VIN(ILIM)
h_PROG
Charge Pump FB Pin Input Leakage
CLK Frequency
V_{CPO_FB} = 1.3V
Effective Open-Loop Output Impedance (Note 4) V_CPO = 4.5V, C_FLY = 1μF
PROG Pin Servo Voltage
Input Current Limit
Ratio of V_IN Input Current Limit to PROG Pin
Current
V_{CPO_FB} < 1.2V
R_PROG = 33.3k, V_CPO = 0V
R_PROG = 33.3k, V_CPO = 0V
l –50
50
0.75 0.9 1.05
6
l 0.98 1.0 1.02
360
10,500
I_CHRG(1x)
I_CHRG(2x)
I_SC
V_MODE
CPO Pin Charging Current (1x Mode)
CPO Pin Charging Current (2x Mode)
Short-Circuit Charge Current
V_IN to CPO Voltage Differential for Switching
Mode from 1x to 2x
V_IN = 3.8V, R_PROG = 33.3k, V_CPO = 3V
R_PROG = 33.3k
PROG Pin Grounded, V_CPO = 0V
315
157.5
600
200
1x/2x Mode Comparator Hysteresis
120
V_CLAMP
Maximum Voltage Across Either Supercapacitor
After Charging
l
2.65 2.75
V_STACK
VMID
Maximum Supercapacitor Stack Voltage
VMID Output Voltage
l
5.3
5.5
2.5
VMID Current Sourcing Capability
VMID Current Sinking Capability
CPO_FB Pin Threshold Voltage (Rising) for
CAPGOOD
VMID < V_CPO/2, V_{CPO_FB} > 1.24V
VMID > V_CPO/2, V_{CPO_FB} > 1.24V
4.5
5.5
l 1.09 1.11 1.13
CPO_FB Pin Hysteresis for CAPGOOD
20
CAPGOOD Output Low Voltage
CAPGOOD High Impedance Leakage Current
I_SINK = 5mA
V_CAPGOOD = 5V
65
l
1
UNITS
V
μA
μA
μA
μA
μA
mV
mV
mV
V
mV
nA
MHz
Ω
V
mA
A/A
mA
mA
mA
mV
mV
V
V
V
mA
mA
V
mV
mV
μA
3226fa
3