P9415-R Datasheet

© 2021 Renesas Electronics Corporation

27

May 4, 2021

8.3.3 Over-Voltage Protection

If

VRECT voltage increases above 90% of the OVP voltage set point, the P9415-R turns on the internal clamp to bring the rectifier voltage back

to a safe operating level. If the Vrect voltage increases above the OVP voltage set point, the P9415-R sends an interrupt to the AP to notify

Over-voltage condition. The internal clamp is released when the VRECT voltage falls below 90% of the OVP voltage set point. The default OVP

voltage setpoint is 18.04V for EPP and 14.66V for BPP mode and both are programmable.

8.3.4 Over-Current Protection, Over-Temperature Protection, and Thermal Shutdown

The P9415-R uses over-current (OC) protection and over-temperature (OT) protection by sending an interrupt to the AP if the output current or

die temperature exceeds the operating limits.

If an over-current condition exists, over-current Warning interrupt is sent early to the AP before Iout reaches the over-current limit threshold

(1.5A default) with the expectation that the AP will respond by reducing the output consumption being drawn from P9415-R. If the output current

reaches the over-current limit threshold, Vout starts to drop without increasing current.

If the die temperature exceeds over-temperature threshold1 (default 105°C), the P9415-R first sends an interrupt (OTP) to the AP to alarm

over-temperature condition and starts OTP timer (180sec default). If the temperature falls below over-temperature threshold1 – hysteresis, OTP

timer resets. If the die temperature keeps increasing and exceeds over-temperature threshold2 (default 120°C) or OTP timer expires, the

P9415-R sends an End Power Transfer Packet to the transmitter to terminate a power transfer. If the temperature keeps increasing and exceeds

the thermal shutdown threshold (typical 140°C), the P9415-R turns off output LDO.

8.3.5 Enable Input

The P9415-R offers an active LOW enable the function that allows the host AP to control when wireless power will be enabled. When /EN pin

is pulled high, the P9415-R is suspended and placed in low current mode. If pulled low, P9415-R is active. /EN pin should never be left floating.

In addition, the P9415-R should not be disabled with /EN when the device is in the power transfer phase. Wireless power transfer should be

terminated via an EPT command and then once power is removed, /EN high can be asserted.

8.3.6 LDO Regulators

The P9415-R has three LDOs. The Main LDO (VOUT pin) is programmable from 5V to 20V and LDO5P0 is powered by VRECT. LDO1P8 is

powered by LDO5P0. Both LDO5P0 and LDO1P8 are used for supplying power to internal low voltage blocks. The LDOs must have local

ceramic bypass capacitors placed near the P9415-R.

8.3.7 MLDO Output Enable Conditions

In the BPP mode after entering the power transfer phase, the P9415-R starts sending control error packets with high value to raise the VRECT

voltage close to its target value and starts a 2-second timer. The P9415-R enables the MLDO when the VRECT voltage reaches the target

voltage or the 2-second timer expires.

In the EPP mode, the P9415-R starts a 5-second timer while exiting the Negotiation phase and waits for the Tx acknowledgment (ACK) in the

Calibration Mode1 phase. The P9415-R enables the MLDO when it receives ACK from Tx in Calibration Mode1 phase or the 5-second timer

expires.