8. FUNCTIONAL DESCRIPTION
S1F76980 Technical Manual (Rev.1.0)
EPSON
15
8.4 Recommended IC Protection Circuit
The following external circuits for protection of IC are recommended.
(1) Measures against reverse insertion of V
CC
power supply
Reverse insertion of power supply causes an IC breakage. Using the following external circuit configuration
prevents an IC breakage.
Fig.8.5.1 V
CC
power supply reverse-insertion support circuit
(2) Measures against input power supply floating
Causing the floating state by removing the input power supplies (V
CC
, V
BUS
, and V
BAT
) may eliminate the load
and reach the midpoint potential. This state is not effective for the IC, so we recommend that the IC be
connected to a discharge resistor. The recommended resistance value is between 1 and 2.2 Meg
Ω
. If a lower
resistance is required depending on setting conditions, however, determine the appropriate value after careful
evaluation.
FB
V
CC
(-)
V
BAT
(-)
V
OUT
OC2
OC1
OB2
OB1
V
OUT
ON
ON
OFF
OFF
V
CC
(+)-3V
V
CC
V
SS
V
BAT
(+)+3V
Back-flow
prevention
Back-flow
prevention
Current
limiter
