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MODEL 7700 SERIES

Power Factor Correction Power Module

MODEL 7700 SERIES
Power Factor Correction Power Module
NEW HIGHER POWER VERSION
MODELS / RANGE
7700B 7700-2A
FEATURES AND BENEFITS
1, 500 Watts / 3, 000 Watts 2, 000 Watts / 4, 000 Watts
· Module contains all power components necessary to provide power factor correction in a switching power supply. - Rectifier bridge with SCRs for inrush current limiting - Ultrafast platinum output diode - 500V .1 Max. FET (7700B) - Low gate charge, 500V, .0675 max. FET (7700-2A) · Provides optimum use of available line current · Allows power supply to meet harmonic requirement · Module design reduces cost of heat sink · Saves significant space and assembly time · Low cost · Internal temperature sensing · Replaces up to 10 each TO-220 or TO-247 discrete power semiconductors · Custom module versions available to meet specific requirements such as: - Motor drives - Power servo amplifiers - Solenoid drivers - Solid state relays - 3 phase rectifier bridges
APPLICATIONS
Designed to optimally facilitate a boost type power factor correction (PFC) system for designs with up to 36A rms input current.
Specifications subject to change without notice.
Standard applications include switching power supplies from 1, 000 watts to 4, 000 watts with line voltages up to 300 V rms.
Model 7700 Series
ELECTRICAL CHARACTERISTICS
Parameter MOS FET Continuous Drain Current
Symbol ID
Model B -2A B -2A B -2A B -2A B -2A B -2A B, -2A B, -2A B -2A B, -2A B, -2A B B B -2A -2A -2A B -2A B -2A B -2A B -2A B -2A B -2A B, -2A B -2A
Pulsed Drain Current
Model 7700 Series
ELECTRICAL CHARACTERISTICS
Parameter SCRS Average On Current RMS On Current (As AC switch) Peak Repetitive Off Voltage
Symbol IT(AV) IRMS
Model B -2A B -2A B -2A B -2A B -2A B -2A B, -2A B, -2A B, -2A B, -2A B, -2A B, -2A B -2A B -2A B, -2A B -2A
Max. 20 35 30 55 600 800 300 400 25 300 1.6 1.6 3.5 1.5 1.5 60 120 35 100 100
VRRM / VDRM Peak One Cycle Non-Repetitive ITSM Surge Current Reverse and Direct Leakage IR / ID Current On Voltage VT Gate Trigger Voltage (Includes drop across RG) Gate Trigger Current (Each SCR Individually) Holding Current Internal Gate Resistor Junction Temperature Thermal Resistance Bridge Diodes Average Forward Current Peak Repetitive Reverse Voltage Peak One Cycle Non-Repetitive Surge Current Reverse Leakage Current Forward Voltage Junction Temperature Thermal Resistance VGT
IH RG Tj Rthjc
IF(AV) VRRM IFSM IR / VF TJ RTHJC
B -2A B -2A B -2A B -2A B -2A B, -2A B -2A
Model 7700 Series
ELECTRICAL CHARACTERISTICS
Parameter Output Diode Average Forward Current Peak Repetitive Reverse Voltage Peak One Cycle Non-Repetitive Surge Current Reverse Leakage Current Forward Voltage Reverse Recovery Time Junction Temperature Thermal Resistance TH1 NTC Thermistor Resistance Resistance Ratio
Symbol IF(AV) VRRM IFSM IR / VF trr TJ RTHJC
Model B -2A B, -2A B -2A B -2A B -2A B -2A B, -2A B -2A
Max. 24 60 600 500 500 60 1 2.8 2.8 35 40 175
R25 RT / R25
Dissipation Constant Thermal Time Constant
B, -2A B, -2A B, -2A B, -2A B, -2A B, -2A B, -2A
Model 7700 Series
SYSTEM DIAGRAM
EMI Filter
AC Line
Dotted line denotes BI Model 7700 and associated pins. 14 Pin 1: AC 1 Pin 2: AC 2 Pin 3: Bridge Output Pin 4: SCR Gates Pin 5: Ground Pin 6: Ground Pin 7: FET Drain Pin 8: Ultrafast Anode Pin 9: Ultrafast Cathode Pin 10: Gate Ground Pin 11: Gate Drive Pin 12: N.C. Pin 13: TH 1 Pin 14: TH 2 13 12 Thermal Shutdown Circuitry 11 10 Gate Driver 6
PFC PWM
Model 7700 Series
OUTLINE DIMENSIONS (Inch)
R .235
.160 Ref. Pin 1 6X .175 .075 Ref. 6X .275 .330
Part Number
Lot Number
Date Code
ORDERING INFORMATION
77 Model Package
Model 7700 Series
MODEL 7700 APPLICATION NOTES
OUTPUT VOLTAGE OUTPUT CAPACITOR
The dc output voltage must be greater than the highest peak line voltage expected:
The output capacitor size is often limited by the line dropout requirements of the power supply:
DISCONTINUOUS CONDUCTION
2 x POUT x td VO2 - VO MIN2
When the line voltage approaches zero volts the PFC PWM will be forced towards its maximum duty cycle. This will cause the current to become discontinuous, which will result in some distortion. The line voltage at which the current will become discontinuous will be:
Where: POUT is the output power, td is the dropout time, and VO MIN is the minimum allowed output voltage. The 120Hz output voltage ripple can be calculated to insure it meets the system requirements:
The line voltage at which the PWM will be duty cycle limited will be:
(2xP) x (2 x1x f xC + ESR) V
The maximum rms 120Hz ripple current will be:
INDUCTOR L1
1.414x PO VO
The 100KHz output voltage ripple will be:
The inductor value controls the amplitude of the 100KHz current ripple. This can greatly effect the amount of distortion and thus the amount of EMI filtering required on the input. Ripple current can be calculated for any point along the input sine wave:
(1.414 x V )
The maximum rms 100KHz ripple current will be:
1.414 x VIN
GATE DRIVE REQUIREMENTS
FET switching times must be fast enough to insure that the FET turns off when the PWM is at maximum duty cycle. Snubbing circuits across the FET will slow the turn off time and should not be used. A discrete gate driver circuit will allow the fastest possible switching times. The Unitrode UC3710 or Telcom TC4422 drivers offer a single chip approach
1.414 x VIN VO
Model 7700 Series
MODEL 7700 APPLICATION NOTES
with only slightly slower switching times. The gate driver must be located as close to the module as possible. Ground sense pin 10 should be used to insure the fastest possible switching times.
HEAT RADIATOR
The heat radiator requirements can be determined by the maximum power dissipated (at low line) and the maximum ambient temperature. The back side of the module should be limited to about 100°C by utilizing the internal thermistor. 100 - TMAX AMB P LOWLINE O
Care should be used when attaching the module to the heat radiator. The screws must be tightened incrementally in a crisscross pattern. A torque limiting screwdriver should be used. The high current levels require currrent sense transformers to maintain a reasonable efficiency. We recommend BI Technologies HM31-20200.
PFC PWM VENDORS
Popular sources are: Unitrode UC3854 Micro Linear ML4812 Linear Technology LT1248
Model 7700 Series