ZHCSIO9A August 2018 – June 2021 TPSM831D31
PRODUCTION DATA
The dynamic phase shedding (DPS) feature allows the TPSM831D31 to dynamically select the number of operational phases for each channel, based on the total output current. This increases the total converter efficiency by reducing unnecessary switching losses when the output current is low enough to be supported by a fewer number of phases, than are available in hardware. The MFR_SPECIFIC_14 and MFR_SPECIFIC_15 commands may be used to configure dynamic phase shedding behavior and thresholds.
The DPS_EN bit in MFR_SPECIFIC_14 may be used to enable or disable dynamic phase shedding. Un-setting (writing to 0b) this bit forces each channel to use the maximum number of available phases, regardless of the output current. DPS is disabled as the factory default.
The phase add/drop thresholds, at which phases are added or dropped are configured based on the peak efficiency point per phase. For a given switching frequency/duty cycle, the efficiency of an individual power stage has a "peak" point, at which switching losses become less significant and conduction losses begin to dominate. For a multiphase converter, the optimum efficiency is achieved when all of the power stages operate as close as possible to their peak efficiency point. For example, consider a 4-phase design, with power stages that have a peak efficiency point of 12 A per phase. When the total output current is 25 A, if all four phases were active, each phase would be supplying 6.25 A, and hence would be operating far away from their peak efficiency point. With only two phases active, however, each phase supplies 12.5A, meaning that each power stage is operating close to its peak efficiency point, therefore the total converter efficiency is higher overall.
In order to maintain regulation during severe load transient events, phases may be added immediately whenever the total peak current reaches phase addition thresholds. To prevent chattering, phases are dropped when the total average current falls below phase drop thresholds, after a delay of 85 µs typically. Phases are always added/dropped, in numerical order. For example, phase 3 is added after phase 2, and dropped after phase 4.
The DPS_COURSE_TH bits in MFR_SPECIFIC_15 select the peak efficiency point per phase. Refer to the power stage datasheet to determine the peak efficiency point per phase.
Phase adding thresholds are configured based on the peak efficiency point per phase. Each phase transition has a configurable threshold of 6 A to 12 A above the peak efficiency point. For example, the threshold at which the converter transitions from 2 phases to 3 phases is determined by the DPS_2TO3_FINE_ADD bits in MFR_SPECIFIC_15. When 8 A is selected, the total peak current which causes the third phase to be added is 2 × IEFF(PEAK) + 8 A. See the register descriptions below for more detailed information.
Likewise, phase drop thresholds are configured based on the peak efficiency point per phase. Each phase transition has a configurable threshold of 2A below A to 4 A above the peak efficiency point. For example, the threshold at which the converter transitions from 3 phases to 2 phases is determined by the DPS_3TO2_FINE_DROP bits in MFR_SPECIFIC_14. When 0 A is selected, the total average current which causes the third phase to be dropped is 2 × IEFF(PEAK). See the register descriptions below for more detailed information.
| PARAMETER | TEST CONDITIONS | MIN | TYP | MAX | UNIT | |
|---|---|---|---|---|---|---|
| VDPSTHA1 | Dynamic phase adding threshold, 1 to 2 Phases (peak current) | Peak Efficiency = 12 A; (MFR_SPECIFIC_15<1:0> = 00b); Offset = 2 A; (MFR_SPECIFIC_15<4:3> = 00b); VRIPPLE ≈ 18 A (estimation) | 21 | 23 | 25 | A |
| Peak Efficiency = 12 A; (MFR_SPECIFIC_15<1:0> = 00b); Offset = 4 A; (MFR_SPECIFIC_15<4:3> = 01b); VRIPPLE ≈ 18 A (estimation) | 23 | 25 | 27 | A | ||
| Peak Efficiency = 12 A; (MFR_SPECIFIC_15<1:0> = 00b); Offset = 6 A; (MFR_SPECIFIC_15<4:3> = 10b); VRIPPLE ≈ 18 A (estimation) | 25 | 27 | 29 | A | ||
| Peak Efficiency = 12 A; (MFR_SPECIFIC_15<1:0> = 00b); Offset = 8 A; (MFR_SPECIFIC_15<4:3> = 11b); VRIPPLE ≈ 18 A (estimation) | 27 | 29 | 31 | A | ||
| Peak Efficiency = 14 A; (MFR_SPECIFIC_15<1:0> = 01b); Offset = 2 A; (MFR_SPECIFIC_15<4:3> = 00b); VRIPPLE ≈ 18 A (estimation) | 23 | 25 | 27 | A | ||
| Peak Efficiency = 14 A; (MFR_SPECIFIC_15<1:0> = 01b); Offset = 4 A; (MFR_SPECIFIC_15<4:3> = 01b); VRIPPLE ≈ 18 A (estimation) | 25 | 27 | 29 | A | ||
| Peak Efficiency = 14 A; (MFR_SPECIFIC_15<1:0> = 01b); Offset = 6 A; (MFR_SPECIFIC_15<4:3> = 10b); VRIPPLE ≈ 18 A (estimation) | 27 | 29 | 31 | A | ||
| Peak Efficiency = 14 A; (MFR_SPECIFIC_15<1:0> = 01b); Offset = 8 A; (MFR_SPECIFIC_15<4:3> = 11b); VRIPPLE ≈ 18 A (estimation) | 29 | 31 | 33 | A | ||
| Peak Efficiency = 16 A; (MFR_SPECIFIC_15<1:0> = 10b); Offset = 2 A; (MFR_SPECIFIC_15<4:3> = 00b); VRIPPLE ≈ 18 A (estimation) | 25 | 27 | 29 | A | ||
| Peak Efficiency = 16 A; (MFR_SPECIFIC_15<1:0> = 10b); Offset = 4 A; (MFR_SPECIFIC_15<4:3> = 01b); VRIPPLE ≈ 18 A (estimation) | 27 | 29 | 31 | A | ||
| Peak Efficiency = 16 A; (MFR_SPECIFIC_15<1:0> = 10b); Offset = 6 A; (MFR_SPECIFIC_15<4:3> = 10b); VRIPPLE ≈ 18 A (estimation) | 29 | 31 | 33 | A | ||
| Peak Efficiency = 16 A; (MFR_SPECIFIC_15<1:0> = 10b); Offset = 8 A; (MFR_SPECIFIC_15<4:3> = 11b); VRIPPLE ≈ 18 A (estimation) | 31 | 33 | 35 | A | ||
| Peak Efficiency = 18 A; (MFR_SPECIFIC_15<1:0> = 11b); Offset = 2 A; (MFR_SPECIFIC_15<4:3> = 00b); VRIPPLE ≈ 18 A (estimation) | 27 | 29 | 31 | A | ||
| Peak Efficiency = 18 A; (MFR_SPECIFIC_15<1:0> = 11b); Offset = 4 A; (MFR_SPECIFIC_15<4:3> = 01b); VRIPPLE ≈ 18 A (estimation) | 29 | 31 | 33 | A | ||
| Peak Efficiency = 18 A; (MFR_SPECIFIC_15<1:0> = 11b); Offset = 6 A; (MFR_SPECIFIC_15<4:3> = 10b); VRIPPLE ≈ 18 A (estimation) | 31 | 33 | 35 | A | ||
| Peak Efficiency = 18 A; (MFR_SPECIFIC_15<1:0> = 11b); Offset = 8 A; (MFR_SPECIFIC_15<4:3> = 11b); VRIPPLE ≈ 18 A (estimation) | 33 | 35 | 37 | A | ||
| VDPSTHS1 | Dynamic phase shedding threshold, 2 to 1 phase (average current) | Peak Efficiency = 12 A; (MFR_SPECIFIC_15<1:0> = 00b); Offset = -6 A; (MFR_SPECIFIC_15<14:13> = 00b) | 4 | 6 | 8 | A |
| Peak Efficiency = 12 A; (MFR_SPECIFIC_15<1:0> = 00b); Offset = -4 A; (MFR_SPECIFIC_15<14:13> = 01b) | 6 | 8 | 10 | A | ||
| Peak Efficiency = 12 A; (MFR_SPECIFIC_15<1:0> = 00b); Offset = -2 A; (MFR_SPECIFIC_15<14:13> = 10b) | 8 | 10 | 12 | A | ||
| Peak Efficiency = 12 A; (MFR_SPECIFIC_15<1:0> = 00b); Offset = 0 A; (MFR_SPECIFIC_15<14:13> = 11b) | 10 | 12 | 14 | A | ||
| Peak Efficiency = 14 A; (MFR_SPECIFIC_15<1:0> = 01b); Offset = -6 A; (MFR_SPECIFIC_15<14:13> = 00b) | 6 | 8 | 10 | A | ||
| Peak Efficiency = 14 A; (MFR_SPECIFIC_15<1:0> = 01b); Offset = -4 A; (MFR_SPECIFIC_15<14:13> = 01b) | 8 | 10 | 12 | A | ||
| Peak Efficiency = 14 A; (MFR_SPECIFIC_15<1:0> = 01b); Offset = -2 A; (MFR_SPECIFIC_15<14:13> = 10b) | 10 | 12 | 14 | A | ||
| Peak Efficiency = 14 A; (MFR_SPECIFIC_15<1:0> = 01b); Offset = 0 A; (MFR_SPECIFIC_15<14:13> = 11b) | 12 | 14 | 16 | A | ||
| Peak Efficiency = 16 A; (MFR_SPECIFIC_15<1:0> = 10b); Offset = -6 A; (MFR_SPECIFIC_15<14:13> = 00b) | 8 | 10 | 12 | A | ||
| Peak Efficiency = 16 A; (MFR_SPECIFIC_15<1:0> = 10b); Offset = -4 A; (MFR_SPECIFIC_15<14:13> = 01b) | 10 | 12 | 14 | A | ||
| Peak Efficiency = 16 A; (MFR_SPECIFIC_15<1:0> = 10b); Offset = -2 A; (MFR_SPECIFIC_15<14:13> = 10b) | 12 | 14 | 16 | A | ||
| Peak Efficiency = 16 A; (MFR_SPECIFIC_15<1:0> = 10b); Offset = 0 A; (MFR_SPECIFIC_15<14:13> = 11b) | 14 | 16 | 18 | A | ||
| Peak Efficiency = 18 A; (MFR_SPECIFIC_15<1:0> = 11b); Offset = -6 A; (MFR_SPECIFIC_15<14:13> = 00b) | 10 | 12 | 14 | A | ||
| Peak Efficiency = 18 A; (MFR_SPECIFIC_15<1:0> = 11b); Offset = -4 A; (MFR_SPECIFIC_15<14:13> = 01b) | 12 | 14 | 16 | A | ||
| Peak Efficiency = 18 A; (MFR_SPECIFIC_15<1:0> = 11b); Offset = -2 A; (MFR_SPECIFIC_15<14:13> = 10b) | 14 | 16 | 18 | A | ||
| Peak Efficiency = 18 A; (MFR_SPECIFIC_15<1:0> = 11b); Offset = 0 A; (MFR_SPECIFIC_15<14:13> = 11b) | 16 | 18 | 20 | A | ||
| VDPSTHA2 | Dynamic phase adding threshold, 2 to 3 phases (peak current) | Peak Efficiency = 12 A; (MFR_SPECIFIC_15<1:0> = 00b); Offset = 4 A; (MFR_SPECIFIC_15<6:5> = 00b); VRIPPLE = 14 A (estimation) | 32.5 | 35 | 37.5 | A |
| Peak Efficiency = 12 A; (MFR_SPECIFIC_15<1:0> = 00b); Offset = 6 A; (MFR_SPECIFIC_15<6:5> = 01b); VRIPPLE = 14 A (estimation) | 34.5 | 37 | 39.5 | A | ||
| Peak Efficiency = 12 A; (MFR_SPECIFIC_15<1:0> = 00b); Offset = 8 A; (MFR_SPECIFIC_15<6:5> = 10b); VRIPPLE = 14 A (estimation) | 36.5 | 39 | 41.5 | A | ||
| Peak Efficiency = 12 A; (MFR_SPECIFIC_15<1:0> = 00b); Offset = 10 A; (MFR_SPECIFIC_15<6:5> = 11b); VRIPPLE = 14 A (estimation) | 38.5 | 41 | 43.5 | A | ||
| Peak Efficiency = 14 A; (MFR_SPECIFIC_15<1:0> = 01b); Offset = 4 A; (MFR_SPECIFIC_15<6:5> = 00b); VRIPPLE = 14 A (estimation) | 36.5 | 39 | 41.5 | A | ||
| Peak Efficiency = 14 A; (MFR_SPECIFIC_15<1:0> = 01b); Offset = 6 A; (MFR_SPECIFIC_15<6:5> = 01b); VRIPPLE = 14 A (estimation) | 38.5 | 41 | 43.5 | A | ||
| Peak Efficiency = 14 A; (MFR_SPECIFIC_15<1:0> = 01b); Offset = 8 A; (MFR_SPECIFIC_15<6:5> = 10b); VRIPPLE = 14 A (estimation) | 40.5 | 43 | 45.5 | A | ||
| Peak Efficiency = 14 A; (MFR_SPECIFIC_15<1:0> = 01b); Offset = 10 A; (MFR_SPECIFIC_15<6:5> = 11b); VRIPPLE = 14 A (estimation) | 42.5 | 45 | 47.5 | A | ||
| Peak Efficiency = 16 A; (MFR_SPECIFIC_15<1:0> = 10b); Offset = 4 A; (MFR_SPECIFIC_15<6:5> = 00b); VRIPPLE = 14 A (estimation) | 40.5 | 43 | 45.5 | A | ||
| Peak Efficiency = 16 A; (MFR_SPECIFIC_15<1:0> = 10b); Offset = 6 A; (MFR_SPECIFIC_15<6:5> = 01b); VRIPPLE = 14 A (estimation) | 42.5 | 45 | 47.5 | A | ||
| Peak Efficiency = 16 A; (MFR_SPECIFIC_15<1:0> = 10b); Offset = 8 A; (MFR_SPECIFIC_15<6:5> = 10b); VRIPPLE = 14 A (estimation) | 44.5 | 47 | 49.5 | A | ||
| Peak Efficiency = 16 A; (MFR_SPECIFIC_15<1:0> = 10b); Offset = 10 A; (MFR_SPECIFIC_15<6:5> = 11b); VRIPPLE = 14 A (estimation) | 46.5 | 49 | 51.5 | A | ||
| Peak Efficiency = 18 A; (MFR_SPECIFIC_15<1:0> = 11b); Offset = 4 A; (MFR_SPECIFIC_15<6:5> = 00b); VRIPPLE = 14 A (estimation) | 44.5 | 47 | 49.5 | A | ||
| Peak Efficiency = 18 A; (MFR_SPECIFIC_15<1:0> = 11b); Offset = 6 A; (MFR_SPECIFIC_15<6:5> = 01b); VRIPPLE = 14 A (estimation) | 46.5 | 49 | 51.5 | A | ||
| Peak Efficiency = 18 A; (MFR_SPECIFIC_15<1:0> = 11b); Offset = 8 A; (MFR_SPECIFIC_15<6:5> = 10b); VRIPPLE = 14 A (estimation) | 48.5 | 51 | 53.5 | A | ||
| Peak Efficiency = 18 A; (MFR_SPECIFIC_15<1:0> = 11b); Offset = 10 A; (MFR_SPECIFIC_15<6:5> = 11b); VRIPPLE = 14 A (estimation) | 50.5 | 53 | 55.5 | A | ||
| VDPSTHS2 | Dynamic phase shedding threshold, 3 to 2 phases (average current) | Peak Efficiency = 12 A; (MFR_SPECIFIC_15<1:0> = 00b); Offset = -4 A; (MFR_SPECIFIC_14<9:8> = 00b) | 17.5 | 20 | 22.5 | A |
| Peak Efficiency = 12 A; (MFR_SPECIFIC_15<1:0> = 00b); Offset = -2 A; (MFR_SPECIFIC_14<9:8> = 01b) | 19.5 | 22 | 24.5 | A | ||
| Peak Efficiency = 12 A; (MFR_SPECIFIC_15<1:0> = 00b); Offset = 0 A; (MFR_SPECIFIC_14<9:8> = 10b) | 21.5 | 24 | 26.5 | A | ||
| Peak Efficiency = 12 A; (MFR_SPECIFIC_15<1:0> = 00b); Offset = 2 A; (MFR_SPECIFIC_14<9:8> = 11b) | 23.5 | 26 | 28.5 | A | ||
| Peak Efficiency = 14 A; (MFR_SPECIFIC_15<1:0> = 01b); Offset = -4 A; (MFR_SPECIFIC_14<9:8> = 00b) | 21.5 | 24 | 26.5 | A | ||
| Peak Efficiency = 14 A; (MFR_SPECIFIC_15<1:0> = 01b); Offset = -2 A; (MFR_SPECIFIC_14<9:8> = 01b) | 23.5 | 26 | 28.5 | A | ||
| Peak Efficiency = 14 A; (MFR_SPECIFIC_15<1:0> = 01b); Offset = 0 A; (MFR_SPECIFIC_14<9:8> = 10b) | 25.5 | 28 | 30.5 | A | ||
| Peak Efficiency = 14 A; (MFR_SPECIFIC_15<1:0> = 01b); Offset = 2 A; (MFR_SPECIFIC_14<9:8> = 11b) | 27.5 | 30 | 32.5 | A | ||
| Peak Efficiency = 16 A; (MFR_SPECIFIC_15<1:0> = 10b); Offset = -4 A; (MFR_SPECIFIC_14<9:8> = 00b) | 25.5 | 28 | 30.5 | A | ||
| Peak Efficiency = 16 A; (MFR_SPECIFIC_15<1:0> = 10b); Offset = -2 A; (MFR_SPECIFIC_14<9:8> = 01b) | 27.5 | 30 | 32.5 | A | ||
| Peak Efficiency = 16 A; (MFR_SPECIFIC_15<1:0> = 10b); Offset = 0 A; (MFR_SPECIFIC_14<9:8> = 10b) | 29.5 | 32 | 34.5 | A | ||
| Peak Efficiency = 16 A; (MFR_SPECIFIC_15<1:0> = 10b); Offset = 2 A; (MFR_SPECIFIC_14<9:8> = 11b) | 31.5 | 34 | 36.5 | A | ||
| Peak Efficiency = 18 A; (MFR_SPECIFIC_15<1:0> = 11b); Offset = -4 A; (MFR_SPECIFIC_14<9:8> = 00b) | 29.5 | 32 | 34.5 | A | ||
| Peak Efficiency = 18 A; (MFR_SPECIFIC_15<1:0> = 11b); Offset = -2 A; (MFR_SPECIFIC_14<9:8> = 01b) | 31.5 | 34 | 36.5 | A | ||
| Peak Efficiency = 18 A; (MFR_SPECIFIC_15<1:0> = 11b); Offset = 0 A; (MFR_SPECIFIC_14<9:8> = 10b) | 33.5 | 36 | 38.5 | A | ||
| Peak Efficiency = 18 A; (MFR_SPECIFIC_15<1:0> = 11b); Offset = 2 A; (MFR_SPECIFIC_14<9:8> = 11b) | 35.5 | 38 | 40.5 | A | ||