Ventev's 18W TSD03 Car Charger Has Compliance Issues with USB Power Delivery
Other than AC wall chargers, Ventev also has USB Type-C car chargers that support USB Power Delivery technology including the Ventev Dashport pd1300 Car Charger and Ventev TSD03 Car Charger.
The Ventev TSD03 Car Charger supports up to 18 watts with 5 volts @ 3 amps, 9 volts @ 2 amps, and 12 volts @ 1.5 amps power profiles using USB Power Delivery 2.0. While the car charger only comes with a single USB Type-C port, it has enough power to support most phones in the market today.
Using the USB Power Test App from Granite River Labs with the Granite River Labs USB Power Delivery Compliance C2 Tester, we ran the following tests on the Ventev TSD03 Car Charger to see how it supports power.
The USB Power Test App first negotiates a power contract for every fixed PDO supported by the Ventev TSD03 Car Charger, and increases the load gradually to find the threshold where over current protection (OCP) kicks in and voltage and current start to drop for safety reasons.
The USB Power Test App also reports out the fixed PDO's supported by the Ventev charger and their OCP thresholds. The OCP thresholds above the maximum current levels for the 9V and 12V PDO's are very high which should just be around 10-20% for best practices.
|PDO#1 Fixed: 5V 3A|
|PDO#2 Fixed: 9V 2A|
|PDO#3 Fixed: 12V 1.5A|
The USB Power Test App takes this data to produce an I-V curve which graphically shows the relationship between voltage and current for each fixed PDO. We can observe for the 9V and 12V PDO's, as the current increases beyond the OCP threshold, the voltage immediately shuts off. The 5V PDO displays a slight current fold-back behavior when crossing OCP even though the charger doesn't support PPS.
We also observed many compliance failures when using the USB Power Delivery Compliance C2 Tester from Granite River Labs to run just a subset of the full USB Power Delivery compliance test suite on the Ventev TSD03 Car Charger.
USB-IF High Level Mapping Summary
Test Group Description
BMC Physical Layer Transmitter
BMC Physical Layer Receiver
BMC Physical Layer Miscellaneous
Protocol Specific Primary
Power Source/Sink Primary
TDA.126.96.36.199 BMC PHY TX EYE
TDA.188.8.131.52 BMC PHY TX BIT
TDA.184.108.40.206 BMC PHY RX INT REJ
TDA.220.127.116.11 BMC PHY RX BUSIDL
TDA.18.104.22.168 BMC PHY TERM
TDA.2.2.1 BMC PROT SEQ GETCAPS
TDA.22.214.171.124 BMC PROT SEQ CHKCAP P PC
TDA.126.96.36.199 BMC PROT SEQ CHKCAP NOMARK P PC
TDA.2.2.7 BMC PROT BIST NOT 5V SRC
TDA.2.2.9 BMC PROT GSC REC
TDA.188.8.131.52 POW SRC LOAD P PC
TDA.184.108.40.206 POW SRC TRANS P PC
BMC Eye Diagram