FSL126HR Fairchild Semiconductor, FSL126HR Datasheet - Page 3

• Manufacturer Part Number: FSL126HR
• Description: Power Switch ICs - POE / LAN Green Mode Fairchild Power Switch (FPS)
• Manufacturer: Fairchild Semiconductor

Specifications of FSL126HR

• Number Of Switches: Single
• On Resistance (max): 6.2 Ohms
• On Time (max): 23 ns
• Off Time (max): 17.2 ns
• Supply Voltage (max): 26 V
• Maximum Operating Temperature: + 105 C
• Minimum Operating Temperature: - 40 C
• Package / Case: DIP-8
• Maximum Power Dissipation: 1.5 W
• Mounting Style: Through Hole
• Operating Frequency: 100 KHz
• Switch Configuration: Single
• Switch Current (typ): 1.5 A
• Lead Free Status / Rohs Status: Details

© 2011 Fairchild Semiconductor Corporation
FSL126HR • Rev. 1.0.0
Pin Configuration
Pin Definitions
6, 7, 8
Pin #
1
2
3
4
5
Name
Drain
GND
V
V
V
I
PK
STR
CC
FB
Description
Ground. SenseFET source terminal on the primary side and internal control ground.
Positive Supply Voltage Input. Although connected to an auxiliary transformer winding,
current is supplied from pin 5 (V
V
power is supplied via the auxiliary transformer winding.
Feedback Voltage. The non-inverting input to the PWM comparator, it has a 0.4mA current
source connected internally, while a capacitor and opto-coupler are typically connected
externally. There is a delay while charging external capacitor C
internal 5µA current source. This delay prevents false triggering under transient conditions, but
still allows the protection mechanism to operate under true overload conditions.
Peak Current Limit. Adjusts the peak current limit of the SenseFET. The feedback 0.4mA
current source is diverted to the parallel combination of an internal 6kΩ resistor and any
external resistor to GND on this pin to determine the peak current limit.
Startup. Connected to the rectified AC line voltage source. At startup, the internal switch
supplies internal bias and charges an external storage capacitor placed between the V
and ground. Once V
Drain. Designed to connect directly to the primary lead of the transformer and capable of
switching a maximum of 650V. Minimizing the length of the trace connecting these pins to the
transformer decreases leakage inductance.
CC
reaches the UVLO upper threshold (12V), the internal startup switch opens and device
CC
Figure 3. Pin Configuration
reaches 12V, the internal switch is opened.
STR
) via an internal switch during startup (see Figure 2). Once
3
FB
from 2.4V to 6V using an
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CC
pin