Datasheet InnoSwitch3-Pro (Power Integrations) - 7

InnoSwitch3-Pro
feedback loop of the IC features 10 mV (∆V ) voltage change In the case when the MCU loses communication with the secondary OUT resolution. The programmable current set point features 20% to control er, a watchdog timer triggers a reset to reassert a safe 5 V 100% operating range, with a programming step size of 0.8% of full condition and opens the series bus switch. scale current. Below 5 V and for load current less than 50 mA,
Telemetry Feature
voltage command step size of 10 mV may result in non-montonicity The control er communicates to the MCU to report back the status of since operating frequency is very low. the power supply. Output voltage and current is measured by
Internal uVCC Generation, Bus Switch Driver and Discharge
internal ADC and available to MCU through I2C. The telemetry The internal LDO generates 3.6 V uVCC for MCU which simplifies the features also covers CV, CC and constant power set points, OV/UV system design. InnoSwitch3-Pro also has an internal driver that thresholds, all protection settings, interrupt status, and complete guarantees turn-on of an n-channel FET series bus switch with source fault status. voltage as high as 24 V. The VB/D pin which enables the bus switch
Minimum Off-Time
is also configurable as the discharge path for the load. The secondary control er initiates a cycle request using the inductive-
Programmable Protections
connection to the primary. The maximum frequency of secondary- User programmable protection features include output undervoltage cycle requests is limited by a minimum cycle off-time of t . This OFF(MIN) (UV) and overvoltage (OV) protection and over-temperature protec- is in order to ensure that there is sufficient reset time after primary tion. The UV/OV thresholds are dynamical y programmable. Users conduction to deliver energy to the load. can program three responses to these protections, including
Maximum Switching Frequency
auto-restart, latch-off and no-response. An auto-restart (AR) or The maximum switch-request frequency of the secondary control er latch-off (LO) response does not inherently open the series bus is f . switch. The I2C master must send a command to open it if this is the SREQ desired behavior.
Frequency Soft-Start
At start-up the primary control er is limited to a maximum switching The secondary control er also features generation of an interrupt frequency of f and 70% of the maximum programmed current limit signal if one or more of the faults is detected. The SCL pin is pulled SW down for ~55 ms to generate an interrupt for MCU. -8147-102816 Request Window PI Output Voltage
FORWARD Pin Voltage Time Primary VDS Time
Figure 8. Intelligent Quasi-Resonant Mode Switching.
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Rev. G 07/19 www.power.com Document Outline Product Highlights Description Output Power Table Pin Functional Description InnoSwitch3-Pro Functional Description Primary Controller Secondary Controller Register Definition Command Registers Telemetry (Read-back) Registers I2C Connection I2C Example Waveforms Applications Example Key application Considerations Selection of Components Components for InnoSwitch3-Pro IC Primary-Side Circuit Components for InnoSwitch3-PRO Secondary-Side Circuit Recommendations for Circuit Board Layout Layout Example Recommendations for Transformer Design Application Considerations for INN3379C and INN3370C Only Quick Design Checklist Theremal Resistance Test Conditions for INN3379C and INN3370C Absolute Maximum Ratings Thermal Resistance Key Electrical Characteristics Typical Performance Curves InSOP-24D Package Drawing Part Ordering Table MSL Table ESD and Latch-Up Table Part Ordering Information