Datasheet INN5375F, INN5376F, INN5377F, INN5396F, INN5475F, INN5476F, INN5477F, INN5496F (Power Integrations) - 6

InnoSwitch5-Pro
The most likely event that could require an additional handshake is
Programmable Voltage and Current
when the primary stops switching as the result of a momentary line The operating voltage and current set points are set fully programmable brown-out event. When the primary resumes operation, it will default through I2C interface. The output voltage is fully user programmable to a start-up condition and attempt to detect handshake pulses from with a range from 3 V to 30 V. The fast response feedback loop of the secondary. the IC features 10 mV (∆VOUT) voltage change resolution. The programmable current set point features 15% to 100% operating If secondary does not detect that the primary responds to switching range, with a programming step size of 0.52% of full scale current. requests for 8 consecutive cycles, or if the secondary detects that the Below 5 V and for load current less than 50 mA, voltage command primary is switching without cycle requests for 4 or more consecutive step size of 10 mV may result in non-montonicity since operating cycles, the secondary control er will initiate a second handshake frequency is very low. sequence. This provides additional protection against cross-conduction of the SR FET while the primary is switching. This protection mode
Minimum Off-Time
also prevents an output overvoltage condition in the event that the The secondary control er initiates a cycle request using the FluxLink primary is reset while the secondary is still in control. connection to the primary. The maximum frequency of secondary- cycle requests is limited by a minimum cycle off-time of t . This
Wait and Listen
OFF(MIN) is in order to ensure that there is sufficient reset time after primary When the primary resumes switching after initial power-up recovery conduction to deliver energy to the load. from an input line voltage fault (UV or OV) or an auto-restart event, it will assume control and require a successful handshake to relinquish
Maximum Switching Frequency
control to the secondary control er. The maximum switch-request frequency of the secondary control er is f . As an additional safety measure the primary will pause for an SREQ auto-restart on-time period, t (~82 ms), before switching. During
Internal uVCC Generation, Bus Switch Driver and Discharge
AR this “wait” time, the primary will “listen” for secondary requests. If it The internal LDO generates 3.6 V uVCC for MCU which simplifies the sees two consecutive secondary requests, separated by ~30 ms, the system design. InnoSwitch5-Pro also has an internal driver that primary will infer secondary control and begin switching in slave guarantees turn-on of an n-channel FET series bus switch with mode. If no pulses occurs during the t “wait” period, the primary source voltage as high as 30 V. The VB/D pin which enables the bus AR will begin switching under primary control until handshake pulses are switch is also configurable as the discharge path for the load. received.
Programmable Protections Secondary Controller
User programmable protection features include output undervoltage (UV) and overvoltage (OV) protection and over-temperature As shown in the block diagram in Figure 4, the IC is powered by a protection. 4.5 V (V ) regulator which is supplied by either VOUT or FWD. The BPS SECONDARY BYPASS pin is connected to an external decoupling The UV/OV thresholds are dynamical y programmable. Users can capacitor and fed internal y from the regulator block. program four responses to these protections, including auto-restart, latch-off, disable output, and no-response. An auto-restart (AR) or The FORWARD pin also connects to the negative edge detection latch-off (LO) response does not inherently open the series bus block used for both handshaking and timing to turn on the SR FET switch. The I2C master must send a command to open it if this is the connected to the SYNCHRONOUS RECTIFIER DRIVE pin. The desired behavior. FORWARD pin voltage is used to determine when to turn off the SR FET in discontinuous mode operation. This is when the voltage The secondary control er also features generation of an interrupt across the R of the SR FET drops below zero volts. signal if one or more of the faults is detected. The SCL pin is pulled DS(ON) down for ~55 ms to generate an interrupt for MCU. In continuous conduction mode (CCM) the SR FET is turned off before the pulse request is sent to the primary to demand the next In the case when the MCU loses communication with the secondary switching cycle, providing excel ent synchronous operation, free of control er, a watchdog timer triggers a reset to reassert a safe 5 V any overlap for the FET turn-off. condition and opens the series bus switch. The output voltage is regulated on the VOUT pin and defaults to 5 V
Telemetry Feature
at start-up. The control er communicates to the MCU to report back the status of the power supply. Output voltage and current is measured by internal The external current sense resistor connected between ISENSE and ADC and available to MCU through I2C. The telemetry features also SECONDARY GROUND pins is used to regulate the output current in covers CV, CC and constant power set points, OV/UV thresholds, all constant current regulation mode. protection settings, interrupt status, and complete fault status.
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Rev. C 01/24 www.power.com