Datasheet

OUT REF
V V R1 R2
R1
tol = tol + tol + tol
R1 + R2
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VIN(POWERUP)
VIN
VOUT
5V or 3.3V
0
0
OUT REF
R1
V = V 1 +
R2
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TPS7A6201-Q1
www.ti.com SLVSAA0B –NOVEMBER 2010–REVISED MARCH 2012
DETAILED DESCRIPTION
TPS7A6201 is a monolithic low dropout linear voltage V
REF
= reference voltage (V
REF
= 1.23 V typically)
regulator with programmable output voltage and an
R1, R2 = feedback resistors (see Figure 3)
integrated fault protection. This voltage regulator is
designed for low power consumption and quiescent
The overall tolerance of the regulated output voltage
current less than 25µA in light load applications.
depends on the tolerance of internal reference
This device is available in two 5 pin package options
voltage and external feedback resistors, and is given
as follows:
by Equation 2.
• KTT/ D2PAK
(2)
The following section describes the features of
TPS7A6201 voltage regulator in detail.
Where,
tol
VOUT
= tolerance of output voltage
Power Up
tol
VREF
= tolerance of internal reference voltage
During power up, the regulator incorporates a
(tol
VREF
= ± 1.5% typically)
protection scheme to limit the current through pass
element and output capacitor. When the input voltage
tol
R1
,tol
R2
= tolerance of feedback resistors R1, R2
exceeds a certain threshold (VIN
(POWERUP)
) level, the
output voltage begins to ramp up as shown in
For a tighter tolerance on V
OUT
, lower-value feedback
Figure 18.
resistors can be selected. It is recommended to
select feedback resistors such that the sum of R1 and
R2 is between 20kΩ and 200kΩ.
Enable Input
This device has a high voltage tolerant EN pin that
can be used to enable and disable a device from an
external microcontroller or a digital control circuit. A
high input to this pin activates the device and turns
the regulator on. This input can also be connected to
V
IN
terminal for self bias applications. An internal pull
down resistor is connected to this pin, and therefore if
this pin is left unconnected, the device will stay
disabled.
Charge Pump Operation
This device has an internal charge pump which turns
on or off depending on the input voltage and the
Figure 18.
output current. The charge pump switching circuitry
shall not cause conducted emissions to exceed
required thresholds on the input voltage line. For a
Adjustable Output Voltage
given output current, the charge pump stays on at
The regulated output voltage (V
OUT
) can be
lower input voltages and turns off at higher input
programmed by connecting external resistors to FB
voltages. The charge pump switching thresholds are
pin. The feedback resistor values can be calculated
hysteretic. Figure 19 and Figure 20 shows typical
using Equation 1.
switching thresholds for the charge pump at light (I
OUT
< ~2mA) and heavy (I
OUT
> ~2mA) loads respectively.
(1)
Where,
V
OUT
=desired output voltage
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