viper53esp STMicroelectronics, viper53esp Datasheet - Page 7

• Manufacturer Part Number: viper53esp
• Description: Off-line Primary Switch
• Manufacturer: STMicroelectronics

VIPer53EDIP - E / VIPer53ESP - E
3
Pin connections and function
Figure 1.
Figure 2.
Table 10.
Pin Name
SOURCE
DRAIN
COMP
TOVL
OSC
SOURCE
SOURCE
V
DD
COMP
OSC
1
2
3
4
Pin connection (top view)
Current and voltage conventions
Pin function
Power supply of the control circuits. Also provides the charging current of the external
capacitor during start-up.
The functions of this pin are managed by four threshold voltages:
- VDDon: Voltage value at which the device starts switching (Typically 11.5 V).
- VDDoff: Voltage value at which the device stops switching (Typically 8.4 V).
- VDDovp: Triggering voltage of the overvoltage protection (Trimmed to 18 V).
Power MOSFET source and circuit ground reference.
Power MOSFET drain. Also used by the internal high voltage current source during
the start-up phase, to charge the external V
Allows the setting of the dynamic characteristic of the converter through an external
passive network. The useful voltage range extends from 0.5V to 4.5V. The Power
MOSFET is always off below 0.5V, and the overload protection is triggered if the
voltage exceeds 4.35V. This action is delayed by the timing capacitor connected to the
TOVL pin.
Allows the connection of an external capacitor for delaying the overload protection,
which is triggered by a voltage on the COMP pin higher than 4.4V.
Allows the setting of the switching frequency through an external Rt-Ct network.
DIP-8
V
DD
I
DD
V
OSC
8
7
6
5
I
OSC
TOVL
VDD
NC
DRAIN
OSC
V
TOVL
DocRev1
I
15V
TOVL
TOVL
VDD
Pin Function
V
COMP
I
COMP
COMP
TOVL
DRAIN
VDD
NC
NC
NC
DD
SOURCE
capacitor.
DRAIN
Pin connections and function
1
2
3
4
5
PowerSO-10
I
D
V
DS
10
9
8
7
6
SOURCE
NC
NC
OSC
COMP
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