Datasheet AP43770 (Diodes) - 5

AP43770 Performance Characteristics
The AP43770 includes a USB Type-C power delivery controller, which meets USB Power Delivery specification Rev3.0 v1.1. Because of its high voltage process, the AP43770 provides a cost-effective solution without requiring external discrete high voltage components, such as LDO, TL431, CC/CV, pre-driver for external PMOS power switch, buck or boost converter, etc. Meanwhile, it can provide robust protection scheme with built-in OVP/OCP/SCP/OTP features. What’s more, it supports on-chip multi-time-programmable (MTP) for maximum four times during the configuration and ID data programming. In consideration of the quick charge protocol migrating in portable device, the AP43770 supports options for QC4/4+,QC3.0/2.0 and BC 1.2. All of these protocols can be turned on or off and identified automatically. It can be configured with practical applications of users.
T C System Power-On Sequence U
When the external power source is provided, the AP43770 wakes up after the power-on reset (V_RST ~ 2.8V), then the internal 5V_LDO and
D
1.8V_LDO are settled, and the USB PD controller and MCU would be initialized. All analog control blocks are ready and waiting for PD negotiation
O
process. Meanwhile, the AP43770 monitors the voltage and current conditions to avoid abnormal conditions. Once any unacceptable conditions
R
happen, the AP43770 goes into protection procedure according to the types of abnormal condition.
P W Voltage Transition E
According to the USB PD’s protocol, once the PD device requests different power profiles, the AP43770’s power control block starts to change the
N
voltage and current values. The AP43770 provides corresponding Over-Voltage Protection (OVP), Over-Current Protection (OCP) schemes, and maintains the feedback system stability to guarantee monotonic voltage transition and avoid violating the USB PD electrical specification. The AP43770 provides zero-mismatch voltage methodology which is more flexible for system design requirements of customers. When UFP/DFP makes an acceptable power request deal, the AP43770 changes VFB voltage according to the USB PD command, which is around 1/10 of expected voltage. The voltage regulator control loop (AC/DC or DC/DC) regulates the required VBUS voltage according to VFB voltage. In addition, the shunt regulator is built in to minimize the total external components and the cost.
Protection
The AP43770 supports OVP/UVP/OCP/SCP/OTP and Constant Current (CC) functions. All of the protection thresholds would depend on the requested power profile and provide the most reliable protection scheme. The AP43770 provides the OVP feature by turning off the power switch when VVBUS is 20% higher than the target voltage. Meanwhile, it provides internal discharge path to reduce the overvoltage duration, and terminates discharge current as soon as VVBUS reaches the target voltage. To avoid the VVBUS working abnormally, the AP43770 provides UVP function if the VVBUS is below 75% of the target voltage. To ensure the USB PD safe operation, the AP43770 supports programmable OCP function to make sure output current would not be higher than the allowed maximum current. Once unacceptable conditions happen, the AP43770 would shut down the USB PD system and send “Hard Reset” to the UFP device.
CV/CC
The AP43770 supports Constant Voltage (CV) and Constant Current (CC) functions. The functions can control the output voltage and current by the control pin VFB_OUT and the feedback pins VFB and IFB. During the CV mode, the AP43770 operates in the fixed PDO, and the output voltage will be regulated to the request voltage if the output current is below the allowed maximum current. Once the sink device draws more than IOCP, overcurrent protection occurs. When the CC mode function is enabled, the output voltage drops, and the source current is limited within 150mA of the requested current whenever output current exceeds the allowed maximum current. When the output voltage drops below UVP, constant current limit turns off VBUS and starts error recovery procedure. The AP43770 will reset if the voltage continues dropping to power-on-reset (POR) threshold. AP43770 5 of 9 April 2019 Document number: DS41284 Rev. 5 - 2
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