Datasheet

OUT 1
4
5V R
V
R
´
D »
OUT 1 1 FB
FB 3 4
5V R R V
ΔV =
V R R
æ ö ´
-
ç ÷
è ø
( )
2 3 1 FB
3 4
R R R V
 V
R R
+ ´ ´
D =
´
( )
1 2 3 FB
OUT
3
R R R V
5V
R
+ + ´
=
4.66
4.75
5.15
5.25
0 0.5 1.0 2.0 2.5
Output Current (A)
Output Voltage (V)
1.5
5 V
OUT
with compensation
V
PD_IN
with compensation
5 V
OUT
without compensation
V
PD_IN
without compensation
UDG-12109
5.00
TPS2511
www.ti.com SLUSB18 –JUNE 2012
Figure 34. TPS2511 CS Function
Equation 8 through Equation 11 refer to Figure 33.
The power supply output voltage is calculated in Equation 8.
(8)
5V
OUT
and V
FB
are known. If R
3
is given and R
1
is fixed, R
2
can be calculated. The 5V
OUT
voltage change with
compensation is shown in Equation 9 and Equation 10.
(9)
(10)
If R
1
is less than R
3
, then Equation 10 can be simplified as Equation 11.
(11)
Divide Mode Selection of 5-W and 10-W USB Chargers
The TPS2511 provides two types of connections between the DP pin and the DM pin and between the D+ data
line and the D– data line of the USB connector for a 5-W USB charger and a 10-W USB charger with a single
USB port. For a 5-W USB charger, the DP pin is connectd to the D– line and the DM pin is connected to the D+
line. This is shown in Figure 37 and Figure 38. It is necessary to apply DP and DM to D+ and D– of USB
connector for 10-W USB chargers. See Figure 35 and Figure 36. Table 2. shows different charging schemes for
both 5-W and 10-W USB charger solutions
Table 2. Charging Schemes for 5-W and 10-W USB Chargers
USB CHARGER TYPE CONTAINING CHARGING SCHEMES
5-W Divider1 1.2 V on both D+ and D– Lines BC1.2 DCP
10-W Divider2 1.2 V on both D+ and D– Lines BC1.2 DCP
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