STR-S6525
OFF-LINE SWITCHING REGULATOR
– WITH POWER MOSFET OUTPUT
The STR-S6525 is specifically designed to meet the requirement
for increased integration and reliability in off-line flyback converters
operating in a constant OFF-time mode. The device incorporates the
primary control and drive circuit with a discrete avalanche-rated high-
voltage power MOSFET.
DRAIN
1
2
FAULT
LATCH
OSC.
SOURCE
R
S
3
4
5
6
7
COMMON
SYNC
Crucial system parameters such as maximum ON time and OFF
time are fixed during manufacture. Local control circuit decoupling and
layout are optimized within the device.
FAULT
UVLO
V
IN
FDBK
REF.
Cycle-by-cycle current limiting, soft start, under-voltage lock-out
with hysteresis, over-voltage protection, and thermal shutdown protect
the device during all normal and overload conditions. Over-voltage
protection, thermal shutdown, or an external fault signal be latched.
The dual requirements of dielectric isolation and low transient thermal
impedance and steady-state thermal resistance are satisfied in an over-
molded single-in-line power package.
SOFT START
FAULT-LATCH
TRIGGER
8
9
+
OVER-CURRENT
PROTECTION
Dwg. PK-002-1
Proven in substantial volumes, this device and its fixed-frequency
counterparts represents a significant advance in off-line SMPS reliability
growth and integration.
ABSOLUTE MAXIMUM RATINGS
Supply Voltage, VIN ........................... 35 V
Drain-Source Voltage, VDS .............. 600 V
Continuous Drain Current, ID ............ 6.0 A
1 ms Single-Pulse Drain Current,
IDM ................................................. 24 A
FEATURES
Single-Pulse Avalanche Energy,
EA .............................................. 400 mJ
■ Constant OFF-Time Converter Operating Mode
■ Avalanche-Rated Power MOSFET Switch
■ Pulse-by-Pulse Current Limiting
Feedback Input Current, IFDBK ........ 20 mA
Fault-Latch Trig. Input Current, IFL 1.0 mA
dc ≤ 25%, IFLM ........................... -50 mA
Soft-Start Output Current, ISS ....... -3.0 mA
Over-Current Protection Voltage,
■ Latched Over-Voltage and Thermal Protection
■ Maximum ON Time and OFF Time Set During Manufacture
■ Internal Under-Voltage Lockout with Hysteresis
■ Over-Molded SIP with Integral Isolated Heat Spreader
■ External Synchronization Capability
VOCP ............................................. 3.5 V
Insulation Voltage,VWM(RMS) ........... 2000 V
Package Power Diss., PD ........ See Graph
FET Junction Temperature, TJ ...... +150°C
Internal Frame Temperature, TF ... +125°C
Operating Temperature Range,
TA ............................... -20°C to +125°C
Storage Temperature Range,
Tstg ............................. -30°C to +125°C
Always order by complete part number: STR-S6525 .
™
ALLEGRO [ ALLEGRO MICROSYSTEMS ]
