Datasheet

TPS60200, TPS60201, TPS60202, TPS60203
REGULATED 3.3 V, 100-mA LOW-RIPPLE CHARGE PUMP
LOW POWER DC/DC CONVERTERS
SLVS274 – MARCH 2000
16
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
APPLICATION INFORMATION
typical operating circuit TPS60201 and TPS60203
OUTPUT
INPUT
1.6 V to 3.6 V
OFF/ON
C1
1
µ
F
C2
1
µ
F
C
o
2.2
µ
F
C
i
2.2
µ
F
3
4
5
6
7
8
9
10
R1
Power-Good
IN
EN
C1–
C1+
TPS60201
OUT
C2–
C2+
PG
GND
1,2
Signal
OUTPUT
INPUT
OFF/ON
C1
C2
C
o
2.2
µ
F
C
i
2.2
µ
F
3
4
5
6
7
8
9
10
R1
Power-Good
IN
EN
C1–
C1+
TPS60203
OUT
C2–
C2+
PG
GND
Signal
1,2
0.47 µF
0.47 µF
3.3 V, 100 mA
3.3 V, 50 mA
1.6 V to 3.6 V
Figure 19. Typical Operating Circuit TPS60201 and TPS60203 With Power-Good Detector
power dissipation
The power dissipated in the TPS6020x devices depends mainly on input voltage and output current and is
approximated by:
P
(DISS)
I
O
x 2xV
I
–V
O
for I
(Q)
I
O
(5)
By observing equation 5, it can be seen that the power dissipation is worst for highest input voltage V
I
and
highest output current I
O
. For an input voltage of 3.6 V and an output current of 100 mA the calculated power
dissipation P
(DISS)
is 390 mW. This is also the point where the charge pump operates with its lowest efficiency.
With the recommended maximum junction temperature of 125°C and an assumed maximum ambient operating
temperature of 85°C, the maximum allowed thermal resistance junction to ambient of the system can be
calculated.
R
JA(max)
T
J(MAX)
T
A
P
DISS(max)
125°C 85°C
390 mW
102°C W (6)