tny264 Power Integrations, Inc., tny264 Datasheet - Page 2

• Manufacturer Part Number: tny264
• Description: Enhanced, Energy Ef?cient, Low Power Off-line Switcher
• Manufacturer: Power Integrations, Inc.

Pin Functional Description
DRAIN (D) Pin:
Power MOSFET drain connection. Provides internal operating
current for both start-up and steady-state operation.
BYPASS (BP) Pin:
Connection point for a 0.1 µF external bypass capacitor for the
internally generated 5.8 V supply.
ENABLE/UNDER-VOLTAGE (EN/UV) Pin:
This pin has dual functions: enable input and line under-voltage
sense. During normal operation, switching of the power
MOSFET is controlled by this pin. MOSFET switching is
terminated when a current greater than 240 µA is drawn from
this pin. This pin also senses line under-voltage conditions
through an external resistor connected to the DC line
voltage. If there is no external resistor connected to this pin,
TinySwitch-II detects its absence and disables the line under-
voltage function.
Figure 2. Functional Block Diagram.
2
VOLTAGE
ENABLE/
UNDER-
(EN/UV)
240 µA
BYPASS
TNY263-268
(BP)
G
4/05
ENABLE
1.0 V + V T
1.0 V
50 µA
6.3 V
OSCILLATOR
LINE UNDER-VOLTAGE
JITTER
COUNTER
RESTART
DC MAX
AUTO-
CLOCK
RESET
PRESENT
FAULT
Figure 3. Pin Configuration.
SOURCE (S) Pin:
Control circuit common, internally connected to output
MOSFET source.
SOURCE (HV RTN) Pin:
Output MOSFET source connection for high voltage return.
LIMIT STATE
CURRENT
MACHINE
S
R
SHUTDOWN
THERMAL
5.8 V
4.8 V
Q
Q
EN/UV
BP
+
G Package (SMD-8B)
-
P Package (DIP-8B)
S
S
BYPASS PIN
UNDER-VOLTAGE
1
2
3
4
REGULATOR
5.8 V
BLANKING
CURRENT LIMIT
COMPARATOR
LEADING
EDGE
8
7
5
V I
LIMIT
S (HV RTN)
S (HV RTN)
D
+
-
PI-2643-030701
PI-2685-101600
SOURCE
DRAIN
(D)
(S)