P9222-R/RN Datasheet

© 2019-2022 Renesas Electronics Corporation

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May 5, 2022

5.11 Low Drop-Out (LDO) Regulators

The P9222-R/RN has three LDO regulators. The primary VOUT LDO is powered by VRECT. The VOUT LDO can be programmed to any

voltage between 3.5V and 10V; however, the output voltage setting should be compatible with the wireless Tx capability and coil type. The

LDO5P0 is powered directly from VRECT, and LDO1P8 is powered from LDO5P0. Both are used for supplying power to internal low-voltage

blocks. The LDOs must have local ceramic bypass capacitors placed near the P9222-R/RN. For recommended values, follow the application

schematic in Figure 36.

5.12 MLDO Output Enable Conditions

After the P9222-R/RN is energized wirelessly by a valid Tx and reaches the power transfer state, there are two criteria that must be met prior

to the VOUT MLDO regulator being automatically enabled after start-up. Upon connection to a Tx, the P9222-R/RN sends CEP +55 in order to

drive VRECT up to 6.5V and also starts a 1-second timer to allow VRECT to reach the target. After this timer expires, one of two conditions

must be met before the VOUT output is enabled: CEP values are less than +4 (indicates VRECT has reached the target), or 5 seconds pass.

Either of these events will trigger the P9222-R/RN to enable VOUT. In cases where VRECT is still below the target voltage (5 seconds pass

and VRECT < Vrect_Target), VOUT is enabled in order to allow charging to start. When VRECT is below Vrect_Target, full power charging may

not be possible because the Tx is not providing adequate energy for full power to be transferred.

5.13 Output Power Options

The P9222-R/RN supports configurations such as described in the WPC Baseline Power Profile (BPP) specification. The P9222-R/RN can be

programmed to optimize power delivery for low-power wearable applications and can also provide VOUT and VRECT battery voltage tracking

to reduce losses, further improving efficiency and reducing heat generation during charging.