MC44603P ON Semiconductor, MC44603P Datasheet - Page 20

• Manufacturer Part Number: MC44603P
• Description: Other Power Management Voltage/Current PWM
• Manufacturer: ON Semiconductor
• Type: PWM Mode Controllerr

Specifications of MC44603P

• Input Voltage Range: 18 V
• Mounting Style: Through Hole
• Package / Case: PDIP-16
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

NOTE: Foldback is disabled by connecting Pin 5 to V
Overvoltage Protection
that compares the Pin 6 voltage to V
Figure 47).
comparator noninverting input voltage is nearly equal to:
The comparator output is high when:
overvoltages that last at least 2.0 ms.
output, becomes high. As this level is brought back to the
input through an OR gate, V
the IC output) until V
detected, the output is disabled until V
then re−applied.
in order to limit the circuit startup consumption.
regulator has started to allow the reference V
V
CC
The overvoltage arrangement consists of a comparator
If no external component is connected to Pin 6, the
A delay latch (2.0 ms) is incorporated in order to sense
If this condition is achieved, V
Consequently, when an overvoltage longer than 2.0 ms is
The V
The overvoltage section is enabled 5.0 ms after the
By connecting an external resistor to Pin 6, the threshold
V
level can be changed.
Nominal
disable2
V
V
CC
V
O
CC
out
Figure 46. Foldback Characteristic
is connected after V
11.6 kW ) 2.0 kW
2.0 kW
11.6 kW ) 2.0 kW
ref
à V CC w 17 V
Sequence Initiated
is disabled.
2.0 kW
New Startup
OVP out
ref
x V CC w 2.5 V
OVP out
has reached steady state
remains high (disabling
ref
I
pk max
CC
x V CC
(2.5 V) (refer to
, the delay latch
is removed and
ref
Overload
to stabilize.
I
out
http://onsemi.com
CC
.
20
External
Resistor
V
OVP
6
Figure 47. Overvoltage Protection
0
V
CC
11.6 k
2.0 k
T
2.5 V
2.5 V
(V
Enable
ref
C
Delay
)
OVLO
V
Out
In
ref
τ
5.0 ms
the Output is Disabled)
(If V
In
Delay
2.0 ms
τ
OVP out
Out
= 1.0,
V
OVP out