Fairchild FSB127H User manual

© 2011 Fairchild Semiconductor Corporation 1 FEBFSB127H_T001 • Rev. 1.0.0
User Guide for
FEBFSB127H_T001
Evaluation Board
FSB127H 100kHz Power Switch for
ATX Standby 16W
Featured Fairchild Product:
FSB127H
Direct questions or comments
about this Evaluation Board to:
“Worldwide Direct Support”
Fairchild Semiconductor.com

© 2011 Fairchild Semiconductor Corporation 2 FEBFSB127H_T001 • Rev. 1.0.0
Table of Contents
1.Overview................................................................................................................................... 3
2.Board Configuration ................................................................................................................. 3
3.Schematic.................................................................................................................................. 4
4.PCB Layout............................................................................................................................... 5
5.Test Results............................................................................................................................... 6
5.1.Brown-in / Brownout...................................................................................................... 6
5.2.AC Trim Up and Trim Down ......................................................................................... 6
5.3.Line and Load Regulation .............................................................................................. 6
5.4.DC Output Rise Time..................................................................................................... 7
5.5.DC Transient Response .................................................................................................. 8
5.6.Ripple and Noise ............................................................................................................ 8
5.7.Capacitive Load.............................................................................................................. 9
5.8.Power Saving................................................................................................................ 10
5.9.Efficiency ..................................................................................................................... 10
5.10.Short-Circuit Protection ............................................................................................... 11
5.11.X-Cap Discharge .......................................................................................................... 11
5.12.Over-Power Protection ................................................................................................. 12
5.13.Surge and ESD ............................................................................................................. 12
5.14.EMI Conduction ........................................................................................................... 12
6.Bill of Materials ...................................................................................................................... 13
7.Transformer............................................................................................................................. 14
7.1.Transformer Specification.............................................................................................. 14
8.Revision History ..................................................................................................................... 15

© 2011 Fairchild Semiconductor Corporation 3 FEBFSB127H_T001 • Rev. 1.0.0
This user guide supports the 16W evaluation board for ATX standby using FSB127H. It
should be used in conjunction with the FSB127H datasheet as well as Fairchild’s
application notes and technical support team. Please visit Fairchild’s website at
www.fairchildsemi.com.
1. Overview
The highly integrated FSB-series consists of an integrated Current Mode Pulse Width
Modulator (PWM) and an avalanche-rugged 700V SenseFET. It is specifically designed
for high-performance offline Switch Mode Power Supplies (SMPS) with minimal
external components.
Compared with a discrete MOSFET and controller or RCC switching converter solution,
the FSB-series reduces total component count, design size, and weight while increasing
efficiency, productivity, and system reliability. These devices provide a basic platform
for the design of cost-effective flyback converters, as in PC auxiliary power supplies.
Figure 1. Photo of FEBFSB127H_T001
2. Board Configuration
Input Voltage: 90VAC – 264VAC
Output Voltage: 5V
Output Current: 0 – 3.2A
Operation Frequency: 100kHz

© 2011 Fairchild Semiconductor Corporation 4 FEBFSB127H_T001 • Rev. 1.0.0
3. Schematic
Figure 2. Evaluation Board Schematic

© 2011 Fairchild Semiconductor Corporation 5 FEBFSB127H_T001 • Rev. 1.0.0
4. PCB Layout
Figure 3. Evaluation Board PCB Layout

© 2011 Fairchild Semiconductor Corporation 6 FEBFSB127H_T001 • Rev. 1.0.0
5. Test Results
5.1. Brown-in / Brownout
5.1.1.Test Condition
Decrease input AC voltage gradually and measure the turn-off threshold.
After DC power off, increase input voltage and measure the recovery threshold.
5.1.2.Test Result
RHV=200kΩMinimum Load Maximum Load
Turn off 70 VAC 68 VAC
Turn on 81 VAC 81 VAC
5.2. AC Trim Up and Trim Down
5.2.1.Test Condition
Switch the input voltage from 90V to 264V or from 264V to 90V; the output voltages
should be normal.
5.2.2.Test Result
Minimum Load Maximum Load
90V264V Pass Pass
264V 90V Pass Pass
5.3. Line and Load Regulation
5.3.1.Test Condition
Line regulation: 1% maximum.
Load regulation: 5% maximum.
5.3.2.Test Result
Input Voltage Max. Load Min. Load Load Regulation (%)
90V / 60Hz 4.971V 5.013V 0.84%
264V / 50Hz 4.988V 5.013V
Line Regulation (%) 0.34% 0%

© 2011 Fairchild Semiconductor Corporation 7 FEBFSB127H_T001 • Rev. 1.0.0
5.4. DC Output Rise Time
5.4.1.Test Condition
Load: maximum load and minimum load. DC-output rise time: 20ms, maximum.
5.4.2.Measured Waveforms
Figure 4. 90V / 60Hz Maximum Load Figure 5. 90V / 60Hz Minimum Load
Figure 6. 264V / 50Hz Maximum Load Figure 7. 264V / 50Hz Minimum Load

© 2011 Fairchild Semiconductor Corporation 8 FEBFSB127H_T001 • Rev. 1.0.0
5.5. DC Transient Response
5.5.1.Test Condition
From 10–90% of maximum and minimum load, with a 2.5A/μs slew rate; 5ms/5ms.
5.5.2.Measured Waveforms
Figure 8. 90VAC
/
60Hz Figure 9. 264VAC
/
50Hz
5.6. Ripple and Noise
5.6.1.Test Condition
Tested by DC loading side parallel with a 10μF/EC and 0.1μF/CC capacitor and
measured bandwidth with DC-20MHz.
5.6.2.Measured Waveforms
Figure 10. 90V / 60Hz Maximum Load Figure 11. 90V / 60Hz Minimum Load
Figure 12. 264V / 50Hz Maximum Load Figure 13. 264V / 50Hz Minimum Load

© 2011 Fairchild Semiconductor Corporation 9 FEBFSB127H_T001 • Rev. 1.0.0
5.7. Capacitive Load
5.7.1.Test Condition
Output Capacitive Load = 12000μF
5.7.2.Measured Waveforms
90V / 60Hz Maximum Load 90V / 60Hz Minimum Load
264V / 50Hz Maximum Load 264V / 50Hz Minimum Load

© 2011 Fairchild Semiconductor Corporation 10 FEBFSB127H_T001 • Rev. 1.0.0
5.8. Power Saving
5.8.1.Test Condition
The input wattage is < 1W in Standby Mode with 0.5W loading for 2010 EuP.
The input wattage is < 0.5W in Standby Mode with 0.25W loading for 2013 EuP.
5.8.2.Test Result
FSB127H Input Watts Output Watts
A. When VIN= 230VAC, with 0.5W Loading 0.713W 0.5W
When VIN= 240VAC, with 0.5W Loading 0.715W 0.5W
When VIN= 264VAC, with 0.5W Loading 0.733W 0.5W
B. When VIN= 230VAC, with 0.25W Loading 0.384W 0.25W
When VIN= 240VAC, with 0.25W Loading 0.389W 0.25W
When VIN= 264VAC, with 0.25W Loading 0.406W 0.25W
C. When VIN= 230VAC, with No Loading 53mW x
When VIN= 240VAC, with No Loading 56mW x
When VIN= 264VAC, with No Loading 68mW x
5.9. Efficiency
5.9.1.Test Condition
Measure efficiency at minimum, mid-point, and maximum loading.
5.9.2.Test Result
FSB127H Input Watts Output Watts Efficiency
When VIN= 115V, at 100% Load 20.62W 16W 81.17%
When VIN= 115V, at 75% Load 15.28W 12W 82.42%
When VIN= 115V, at 50% Load 10.02W 8W 82.51%
When VIN= 115V, at 25% Load 5.07W 4W 81.70%
When VIN= 230V, at 100% Load 20.78W 16W 81.40%
When VIN= 230V, at 75% Load 15.11W 12W 82.24%
When VIN= 230V, at 50% Load 10.15W 8W 80.45%
When VIN= 230V, at 25% Load 5.18W 4W 78.62%