IR1110 International Rectifier Corp., IR1110 Datasheet - Page 21

• Manufacturer Part Number: IR1110
• Description: Soft Start Controller Ic In A 64-lead Mqfp Package
• Manufacturer: International Rectifier Corp.

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Dedicated One Phase Operation
The UIN and VIN input terminals are used. No connection is made to WIN.
the watchdog reset time is optimized for 1-phase operation, and 1-phase shutdown is disabled,
regardless of the connection of Pin 13.
Snubber Derived Power Supply
SCRs, to limit dv/dt when the line voltage is switched on.
voltages for the IR1110 and SCR drivers.
the D+ diodes, to create a nominal 15V supply across ZD1 and C1, for the SCR driver.
current flows via D- diodes, to create a nominal -5.1V V
circuits does not exceed about 10mA.
itself serve the IR1110. This is because bus-derived power cannot deliver voltage until after
charging of the DC bus capacitor has already commenced, while the IR1110 must be powered
before charging of the bus capacitor commences.
supplement the snubber derived power. This could be preferred where the AC input line induc-
tance is high, therefore only minimal snubbers - insufficient to furnish the total power required by
the IR1110 and SCR drivers - are needed for dv/dt protection of the SCRs.
The IR1110 can be set for dedicated operation of a 1-phase half-controlled SCR bridge.
When Pin 12 is connected to V
Snubbers will generally be required, either across the AC lines or directly across the
If SCR snubbers are used, the snubber current can be used to derive the power supply
With reference to Figure 10, positive snubber current flows via the three RC snubbers and
A nominal positive 5.1V V
The ZD1 and ZD4 protect the supply voltages against transients on the line voltages.
This power supply circuit requires that the average current consumed by the SCR driver
Note that an auxiliary winding on a DC bus derived switching power supply would not by
It would be possible to use an auxiliary winding on a DC bus derived power supply to
DD
ADVANCE INFORMATION
supply is developed across ZD2 and C2. Negative snubber
SS
, the W timing wave and watchdog circuits are disabled,
SS
supply across ZD3 and C3.
IR1110
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