JAJSF16D march 2013 – september 2020 BQ51013B
PRODUCTION DATA
Figure 9-6 is an example application that shows the BQ51013B used as a wireless power receiver that can power mutliplex between wired or wireless power for the down-system electronics. In the default operating mode, pins EN1 and EN2 are low, which activates the adapter enable functionality. In this mode, if an adapter is not present the AD pin will be low, and AD-EN pin will be pulled to the higher of the OUT and AD pins so that the PMOS between OUT and AD will be turned off. If an adapter is plugged in and the voltage at the AD pin goes above V AD-EN , then wireless charging is disabled and the AD-EN pin will be pulled approximately VAD below the AD pin to connect AD to the secondary charger. The difference between AD and AD-EN is regulated to a maximum of VAD-Diff to ensure the VGS of the external PMOS is protected.
The EN1 and EN2 pins include internal pulldown resistors (RPD), so that if these pins are not connected BQ51013B defaults to AD-EN control mode. However, these pins can be pulled high to enable other operating modes as described in Table 8-2:
EN1 | EN2 | RESULT |
---|---|---|
0 | 0 | Adapter control enabled. If adapter is present then secondary charger is powered by adapter, otherwise wireless charging is enabled when wireless power is available. Communication current limit is enabled. |
0 | 1 | Disables communication current limit. |
1 | 0 | AD-EN is pulled low, whether or not adapter voltage is present. This feature can be used for USB OTG applications. |
1 | 1 | Adapter and wireless charging are disabled, power will not be delivered by the OUT pin in this mode. |
EN1 | EN2 | WIRELESS POWER | WIRED POWER | OTG MODE | ADAPTIVE COMMUNICATION LIMIT | EPT |
---|---|---|---|---|---|---|
0 | 0 | Enabled | Priority(1) | Disabled | Enabled | Not Sent to TX |
0 | 1 | Priority(1) | Enabled | Disabled | Disabled | Not Sent to TX |
1 | 0 | Disabled | Enabled | Enabled(2) | N/A | EPT 0x00, Unknown |
1 | 1 | Disabled | Disabled | Disabled | N/A | EPT 0x01, Charge Complete |
As described in Table 8-3, when EN1 is low, both wired and wireless power are useable. If both are present, priority is set between wired and wireless by EN2. When EN1 is high, wireless power is disabled and wired power functionality is set by EN2. When EN1 is high but EN2 is low, wired power is enabled if present. Additionally, USB OTG mode is active. In USB OTG mode, a charger connected to the OUT pin can power the AD pin. Note that EN1 must be pulled high from an active source (microcontroller). Finally, pulling both EN1 and EN2 high disables both wired and wireless charging.
It is required to connect a back-to-back PMOS between AD and OUT so that voltage is blocked in both directions. Also, when AD mode is enabled no load can be pulled from the RECT pin as this could cause an internal device overvoltage in BQ51013B.