SLUSD53G March 2018 – August 2020 TPS23880
PRODUCTION DATA
COMMAND = 21h with 1 Data Byte, Read/Write
7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
POL4_7 | POL4_6 | POL4_5 | POL4_4 | POL4_3 | POL4_2 | POL4_1 | POL4_0 |
R/W-1 | R/W-1 | R/W-1 | R/W-1 | R/W-1 | R/W-1 | R/W-1 | R/W1 |
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset |
Bit | Field | Type | Reset | Description |
---|---|---|---|---|
7–0 | POLn_7- POLn_0 | R/W | 1 | 1-byte defining 2-Pair PCUTminimum threshold.
The equation defining the PCUT is: PCUT = (N × PCSTEP) Where, when assuming 0.255-Ω Rsense resistor is used: PCSTEP = 0.5 W |
These bits set the minimum threshold for the design. Internally, the typical PCUT threshold is set slightly above this value to ensure that the device does not trip a Pcut fault at or below the set value in this register due to part to part or temperature variation.
For 4-pair wired ports, the 2P Policing values are still applied to the individual channels. See the description for registers 0x2Ah and 0x2Bh for more information on 4-Pair Policing.
The contents of this register is reset to 0xFFh anytime the port is turned off or disabled either due to fault condition or user command
Power Policing:
The TPS23880 implements a true Power Policing limit, where the device will adjust the policing limit based on both voltage and current variation in order to ensure a reliable power limit.
In Semi Auto and Auto modes, these bits are automatically set during power on based on the assigned class (see tables below). If an alternative value is desired, it needs to be set after the PEn bit is set in 0x10h.
Assigned Class | POLn7-0 Settings | Minimum Power |
---|---|---|
Class 1 | 0000 1000 | 4W |
Class 2 | 0000 1110 | 7W |
Class 3 | 0001 1111 | 15.5W |
Class 4 | 0011 1100 | 30W |
Class 5 Dual Signature | 0101 1010 | 45W |
Assigned Class | POLn7-0 Settings | Minimum Power |
---|---|---|
Class 1 | 0000 1000 | 4W(1) |
Class 2 | 0000 1110 | 7W(1) |
Class 3 | 0001 1111 | 15.5W(1) |
Class 4 | 0011 1100 | 30W(1) |
Class 5 | 0100 0000 | 32W(2) |
Class 6 | 0100 1110 | 39W(2) |
Class 7 | 0101 1001 | 44.5W(2) |
Class 8 | 0110 1011 | 53.5W(2) |