LTC1928-5 Datasheet, PDF (3/8 Pages) Linear Technology – Doubler Charge Pump with Low Noise Linear Regulator in ThinSOT

ELECTRICAL CHARACTERISTICS
Note 4: Operating conditions are limited by maximum junction
temperature. The regulated output specification will not apply for all
possible combinations of input voltage and output current. When
operating at maximum input voltage, the output current range may be
limited. When operating at maximum output current, the input voltage
range may be limited.
LTC1928-5
Note 5: CN/SHDN must be driven with a source impedance of at least
100Ω (R_SOURCE) to prevent damage to the part. This pin is multiplexed
and may be connected through a low switch impedance to V_IN. There may
be a large amount of current (V_IN/R_SOURCE) until the shutdown state
occurs after which the charge pump switches at CN/SHDN become high
impedance and the current will fall to < 8µA.
TYPICAL PERFOR A CE CHARACTERISTICS
CPO Output Resistance vs V_IN
35
T_A = 25°C
C_FLY = 0.47µF
30 IOUT = 10mA
25
20
15
10
5
2.5
3.0
3.5
4.0
4.5
V_IN (V)
19285 G01
Shutdown to Enable Timing
(Figure 5)
Min and Max V_CPO vs V_IN
9
T_A = 25°C
8
V_CPO = 2(V_IN)
7
(A)
6
(B)
5
V_CPO = 1.45(V_IN)
4
3
2.5
3.0
3.5
4.0
4.5
V_IN (V)
(A) THE MAXIMUM GENERATED NO LOAD
CPO VOLTAGE
(B) THE MINIMUM ALLOWABLE CPO VOLTAGE,
AT FULL LOAD, TO ENSURE THAT THE LDO
IS NOT DISABLED
19285 G02
Enable to Shutdown Timing
(Figure 5)
2
2
0
0
5
5
4
4
3
3
2
T_A = 25°C
V_IN = 3V
NO LOAD
2 _{TA = 25°C}
1
V_OUT = 5V
I_OUT = 10mA
V_IN = 3V
1 V_OUT = 5V
C_OUT = C_CPO = 4.7µF
C_OUT = 4.7µF
0
0
200µs/DIV
1ms/DIV
19285 G04
19285 G05
V_OUT Transient Response
10
5
0
T_A = 25°C
–5 V_IN = 3V
V_OUT = 5V
–10 COUT = 4.7µF
15
10
5
0
0 50 100 150 200 250 300
TIME (µs)
19285 G03
V_OUT Voltage vs Temperature
5.040
5.030
V_IN = 3V
I_OUT = 10mA
5.020
5.010
5.000
4.990
4.980
–50 –25
0 25 50 75
TEMPERATURE (°C)
100 125
19285 G06
3