Datasheet

VIN(POWERUP)
VIN
VOUT
5V or 3.3V
0
0
ON
OFF
Charge Pump State
9.2
9.6
Hysteresis
V (V)
IN
ON
OFF
Charge Pump State
7.8 7.9
Hysteresis
V (V)
IN
TPS7A6533-Q1
TPS7A6550-Q1
SLVSA98C –MAY 2010–REVISED JULY 2012 www.ti.com
DETAILED DESCRIPTION
voltages. The charge-pump switching thresholds are
TPS7A65xx-Q1 is a family of monolithic low-dropout
hysteretic. Figure 5 and Figure 6 show typical
linear voltage regulators designed for low power
switching thresholds for the charge pump at light (I
OUT
consumption and quiescent current less than 25 µA in
< approximately 2 mA) and heavy (I
OUT
>
light-load applications. Because of an integrated fault
approximately 2 mA) loads, respectively.
protection, these devices are well-suited in power
supplies for various automotive applications.
These devices are available in two fixed-output-
voltage versions as follows:
• 5-V output version (TPS7A6550-Q1)
• 3.3-V output version (TPS7A6533-Q1)
The following section describes the features of
TPS7A65xx-Q1 voltage regulators in detail.
Power Up
During power up, the regulator incorporates a
Figure 5. Charge-Pump Operation at Light Loads
protection scheme to limit the current through the
pass element and output capacitor. When the input
voltage exceeds a certain threshold (V
IN(POWERUP)
)
level, the output voltage begins to ramp up; see
Figure 4.
Figure 6. Charge-Pump Operation at Heavy
Loads
Low-Power Mode
At light loads and high input voltages (V
IN
>
approximately 8 V such that charge pump is off) the
device operates in the low-power mode and the
quiescent current consumption decreases to 25 µA
Figure 4. Power-Up Sequence
(typical) as shown in Table 1.
Table 1. Typical Quiescent Current Consumption
Charge-Pump Operation
I
OUT
Charge Pump ON Charge Pump OFF
These devices have an internal charge pump which
I
OUT
<
turns on or off depending on the input voltage and the
approximately 2 25 µA
250 µA
output current. The charge pump switching circuitry
mA (low-power mode)
does not cause conducted emissions to exceed
(light load)
required thresholds on the input voltage line. For a
I
OUT
>
given output current, the charge pump stays on at
approximately 2
280 µA 70 µA
lower input voltages and turns off at higher input
mA
(heavy load)
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Product Folder Link(s): TPS7A6533-Q1 TPS7A6550-Q1