Power integrations TinySwitch-III Series User Manual

2
E
2/06
TNY274-280
Figure 2. Functional Block Diagram.
Figure 3. Pin Configuration.
Pin Functional Description
DRAIN (D) Pin:
This pin is the power MOSFET drain connection. It provides
internal operating current for both start-up and steady-state
operation.
BYPASS/MULTI-FUNCTION (BP/M) Pin:
This pin has multiple functions:
1. It is the connection point for an external bypass capacitor
for the internally generated 5.85 V supply.
2. It is a mode selector for the current limit value, depending
on the value of the capacitance added. Use of a 0.1
µF
capacitor results in the standard current limit value. Use of
a 1 µF capacitor results in the current limit being reduced to
that of the next smaller device size. Use of a 10 µF capacitor
results in the current limit being increased to that of the next
larger device size for TNY275-280.
3. It provides a shutdown function. When the current into the
bypass pin exceeds 5.5 mA, the device latches off until the
BP/M voltage drops below 4.9 V, during a power down.
This can be used to provide an output overvoltage function
with a Zener connected from the BP/M pin to a bias winding
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
PI-4077-013106
CLOCK
OSCILLATOR
5.85 V
4.9
V
SOURCE
(S)
S
R
Q
DC
MAX
BYPASS/
MULTI-FUNCTION
(BP/M)
+
-
V
I
LIMI
T
FAULT
PRESENT
CURRENT LIMIT
COMP
ARATOR
ENABLE
LEADING
EDGE
BLANKING
THERMAL
SHUTDOWN
+
-
DRAIN
(D)
REGULATOR
5.85
V
BYPASS PIN
UNDER-VOL
TAGE
1.0 V + V
T
ENABLE/
UNDER-
VOLTAGE
(EN/UV)
Q
115 µA 25 µA
LINE UNDER-VOLTAGE
RESET
AUTO-
RESTART
COUNTER
JITTER
1.0 V
6.4
V
CURRENT
LIMIT STAT
E
MACHINE
PI-4078-080905
D
S
BP/
M
S
S
EN/UV
P Package (DIP-8C)
G Package (SMD-8C)
8
5
7
1
4
2
S
6

Power integrations TinySwitch-III Series Specifications

General

Brand	Power integrations
Model	TinySwitch-III Series
Category	Switch
Language	English