Elecom's 18W Power Delivery AC Charger May Look 'Cute' But Has Many USB Power Delivery Compliance Issues

More well known Japanese brands like Elecom sells many types of mobile and PC peripherals including the 18W Power Delivery AC Charger. While offering up to 18 watts of USB Power Delivery charging over Type-C, it can be quite confusing as to which Power Delivery specs the charger actually supports. Even though Elecom has claimed USB Power Delivery 3.0 support on its product page, we verified that the Elecom 18W Power Delivery AC Charger only supports USB Power Delivery 2.0 (see test results below).    

The Elecom 18W Power Delivery AC Charger uses 15 watts (5 volts @ 3 amps), 18 watts (9 volts @ 2 amps) and 18 watts (15 volts @ 1.2 amps) power profiles for fast charging through USB Power Delivery. 18 watts output is enough for most mobile phones sold today such as the Apple iPhone XS Max or Android phones like the Google Pixel 3 XL and the Samsung Galaxy S9+, as well as providing decently fast charging to tablets like the Apple 11-inch iPad Pro (2018). Just make sure to use the Apple USB-C to Lightning Cable if you need to charge your iPhone.

This is how the Elecom 18W Power Delivery AC Charger looks like after it was purchased in Japan. Unlike the typical charger packaging, this one has a lot of information printed on it.

Japan is widely recognized for its unique style of cutesy images which is also reflected on the Elecom 18W Power Delivery AC Charger. This makes it a lot more appealing than most standard chargers especially for Japanese customers.

The Elecom 18W Power Delivery AC Charger serves as a AC wall charger with a single USB Type-C port that comes with foldable prongs to plug into a AC wall socket.

To find out more on the Elecom 18W Power Delivery AC Charger's power capabilities, we used the USB Power Test App from Granite River Labs with the Granite River Labs USB Power Delivery Compliance C2 Tester to generate the following test results.

The USB Power Test App first negotiates a power contract for every PDO supported by the Elecom 18W Power Delivery AC 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 all the PDO's supported by the Elecom charger and their OCP thresholds.

PDO	OCP (A)	%OCP
PDO#1 Fixed: 5V 3A	3.67	122.4%
PDO#2 Fixed: 9V 2A	2.47	123.5%
PDO#3 Fixed: 15V 1.2A	1.44	120.2%

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 PDO. We can observe as the current increases beyond the OCP threshold, the voltage immediately shuts off.

The USB Power Test App can also use the Granite River Labs USB Power Delivery Compliance C2 Tester integrated with the GW Instek APS-7100 programmable AC power supply to compare the charger's power output vs power input so that power efficiency can be measured and compared to regulatory limits from United States of Energy (DOE) Level VI or European Union's CoC Tier 2 requirements. We can repeat the power efficiency tests for different PDO's, current load conditions, and different AC input ranges, allowing us to get a complete picture of power efficiency ranges across all different usage scenarios.

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, we can confirm that the Elecom 18W Power Delivery AC Charger supports USB Power Delivery 2.0. Many compliance failures were also observed for the charger.

Product Capabilities

Parameter	GetCapabilities
USB_PD_SUPPORT	YES
PD_SPECIFICATION_REVISION	2
SOP_CAPABLE	YES
SOP_P_CAPABLE	NO
SOP_PP_CAPABLE	NO
SOP_P_DEBUG_CAPABLE	NO
SOP_PP_DEBUG_CAPABLE	NO
SECURITY_MSGS_SUPPORTED	NO
MANUFACTURER_INFO_SUPPORTED	NO
NUM_FIXED_BATTERIES	0
NUM_SWAPPABLE_BATTERY_SLOTS	0
USB_COMMS_CAPABLE	NO
DR_SWAP_TO_DFP_SUPPORTED	NO
DR_SWAP_TO_UFP_SUPPORTED	YES
UNCONSTRAINED_POWER	YES
UNCHUNKED_EXTENDED_MESSAGES_SUPPORTED	NO

USB-IF High Level Mapping Summary

Sl No	Test Category	Test Group Description	Test Result
1	PHY_PRIMARY_TX	BMC Physical Layer Transmitter	PASS
2	PHY_PRIMARY_RX	BMC Physical Layer Receiver	FAIL
3	PHY_PRIMARY_MISC	BMC Physical Layer Miscellaneous	PASS
4	PROT_PRIMARY	Protocol Specific Primary	FAIL
5	POWER_PRIMARY	Power Source/Sink Primary	FAIL

Result Summary

Sl No	Test ID	Test Name	Test Result
1	TDA.2.1.1.1	TDA.2.1.1.1 BMC PHY TX EYE	PASS
2	TDA.2.1.1.2	TDA.2.1.1.2 BMC PHY TX BIT	PASS
3	TDA.2.1.2.2	TDA.2.1.2.2 BMC PHY RX INT REJ	FAIL
4	TDA.2.1.2.1	TDA.2.1.2.1 BMC PHY RX BUSIDL	PASS
5	TDA.2.1.3.1	TDA.2.1.3.1 BMC PHY TERM	PASS
7	TDA.2.2.1	TDA.2.2.1 BMC PROT SEQ GETCAPS	PASS
8	TDA.2.2.2.1	TDA.2.2.2.1 BMC PROT SEQ CHKCAP P PC	FAIL
9	TDA.2.2.2.2	TDA.2.2.2.2 BMC PROT SEQ CHKCAP NOMARK P PC	PASS
13	TDA.2.2.7	TDA.2.2.7 BMC PROT BIST NOT 5V SRC	PASS
15	TDA.2.2.9	TDA.2.2.9 BMC PROT GSC REC	PASS
16	TDA.2.3.1.1	TDA.2.3.1.1 POW SRC LOAD P PC	PASS
17	TDA.2.3.2.1	TDA.2.3.2.1 POW SRC TRANS P PC	FAIL

BMC Eye Diagram