10.2.1.2.4 VBUS Capacitor and Ferrite Bead
A 1-µF ceramic capacitor is placed close to the TPS65982 VBUS pins. A 6 A ferrite bead is used in this design
along with four high frequency noise 10-nF capacitors placed close to the Type-C connector to minimize noise.
10.2.1.2.5 Soft Start (SS) Capacitor
The recommended 0.22 µF is placed on the TPS65982 SS pin.
10.2.1.2.6 USB Top (C_USB_T), USB Bottom (C_USB_B), and Sideband-Use (SBU) Connections
Although the charger is configured to be only a power source, SBU1/2, USB Top and Bottom must be routed to
the Type C connector. This allows for debugging or for any specific alternate modes for power to be configured if
needed. ESD protection is used in the design on all of these nets as good design practice.
10.2.1.2.7 Port Power Switch (PP_EXT, PP_HV, PP_5V0, and PP_CABLE) Capacitors
The design assumes that a DC-DC converter is connected to the paths where there is significant output
capacitance on the DC-DCs to provide the additional capacitance for load steps. TI recommends to for the
DC-DC converters for to be capable of supporting current spikes which can occur with certain PD configurations.
The PP_EXT path is capable of supporting up to 5 A which will require additional capacitance to support system
loading by the device connected to the charger. A ceramic 10-µF (X7R/X5R) capacitor is used in this design.
This capacitor must at least have a 25 V rating and it is recommended to have 30 V or greater rated capacitor.
The PP_HV path is capable of supporting up to 3 A which will require additional capacitance to support system
loading by the device connected to the charger. A ceramic 10-µF (X7R/X5R) capacitor coupled with a 0.1 µF
high frequency capacitor is placed close to the TPS65982.
The PP_5V0 and PP_CABLE supplies are connected together therefore a ceramic 22-µF (X7R/X5R) capacitor
coupled with a 0.1-µF high-frequency capacitor is placed close to the TPS65982. The PP_5V0 path can support
3 A and the PP_CABLE path supports 600 mA for active Type C PD cables.
The design assumes that a DC-DC converter is connected to the paths where there is significant output
capacitance on the DC-DCs to provide the additional capacitance. It is recommended to for the DC-DC
converters to be capable of supporting current spikes which can occur with certain PD configurations.
10.2.1.2.8 Cable Connection (CCn) Capacitors and RPD_Gn Connections
This charger application is designed to only be a source of power and does not support Dead Battery. RPD_G1
and RPD_G2 must be tied to GND and not connected to the CC1 and CC2 respectively. For CC1 and CC2 lines,
they require a 220 pF capacitor to GND.
10.2.1.2.9 LDO_3V3, LDO_1V8A, LDO_1V8D, LDO_BMC, VOUT_3V3, VIN_3V3, and VDDIO
For all capacitances it is important to factor in DC voltage de-rating of ceramic capacitors. Generally the effective
capacitance is halved with voltage applied.
VIN_3V3 is connected to VDDIO which ensures that the I/Os of the TPS65982’s will be configured to 3.3 V. A
1 µF capacitor is used and is shared between VDDIO and VIN_3V3. LDO_1V8D, LDO_1V8A, and LDO_BMC
each have their own 1 µF capacitor. In this design LDO_3V3 powers the TPS65982’s external flash and various
pull ups. A 10 µF capacitor was chosen to support these additional connections. VOUT_3V3 is not used in this
design and capacitor is not needed.
www.ti.com
TPS65982
SLVSD02E – MARCH 2015 – REVISED AUGUST 2021
Copyright © 2021 Texas Instruments Incorporated
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