Le79489
Table 2. User-Programmable Components (continued)
R
DC1
+ R
DC2
R
FEED
= 2
•
R
FUSE
+
---------------------------------
GDC
40 kΩ + RFA-
GDC =
47.9
------------------------------------
120 kΩ + RFA
Thermal Management Equations (Active, Normal, and Reverse Polarity States)
V
BAT2
– 6 V
-
R
TMG
≥
----------------------------------
I
LOOPmax
V
BAT2
– 7.5 V
R
TMG
≥
---------------------------------------
I
LOOPmax
(OVH = 1)
Data Sheet
The DC feed resistance can be adjusted with a resistance (RFA)
from the RFA pin to ground.
R
TMG
is connected from TMG to VBAT2 and is used to limit
power dissipation within the SLIC in Active states only.
(OVH = 0)
Power dissipated in the thermal management resistor, R
TMG
,
during the Active states.
P
RTMG
(
V
BAT2
– 6 V –
(
I
L
•
R
L
) ) (
R
TMG
)
= -------------------------------------------------------------------------------------------
2
(
R
TMG
+ 40
)
2
(OVH = 1)
2
P
RTMG
(
V
BAT2
– 7.5 V –
(
I
L
•
R
L
) ) (
R
TMG
)
= -----------------------------------------------------------------------------------------------
-
2
(
R
TMG
+ 40
)
(OVH = 0)
Power dissipated in the SLIC while in the Active states.
P
SLIC
=
(
V
BAT2
•
I
L
)
– P
RTMG
– R
L
• (
I
L
)
+ 0.22 W
2
11
Zarlink Semiconductor Inc.
ZARLINK [ ZARLINK SEMICONDUCTOR INC ]
