3 Configuring Two TPSM8D6C24EVM-2PH as a Four-Phase Single Output Evaluation Module

Two TPSM8D6C24EVM-2PH evaluation modules can also be converted into a four-phase single output evaluation module following a similar process as outlined in Section 2 of this application note. The TPSM8D6C24EVM-2V0 and the TPSM8D6C24EVM-2PH have the same reference designators in the same PCB locations. Components are just populated differently and both channels outputs are shorted together on the TPSM8D6C24EVM-2PH. See Figure 1-1, Figure 1-2 and Figure 2-1 for visual reference.

Update board number one with the following changes:

1. Remove R32 (bottom) to make space for programming MSEL2_B for phase 02 of a 4-phase.
2. Install a 8.25-kΩ resistor in the R21 (bottom) location to configure Channel A as the leader (Phase 00) of a 4-phase stack.
3. Install a 68.1-kΩ resistor in the R32 (bottom) location to configure Channel B as a phase 02 of a 4-phase stack. Note: Channel B of board 1 is configured as Phase 02 rather than Phase 01 so that phases within a single module operate 180 degrees out of phase with each other.
4. Add a small signal wire to the SYNC test point (TP15)
5. Add a small signal wire to the VSHAREA test point (TP12)
6. Add a small signal wire to one side of R19 (BCX_CLK)
7. Add a small signal wire to one side of R20 (BCX_DAT)

Update board number-two with the following changes:

1. Remove R12 (Bottom) to disconnect GOSNS/FLWR_A from the output ground
2. Remove R32 (Bottom) to make space for programming MSEL2_B for phase 03 of a 4-phase
3. Install a 10-kΩ resistor in the R5 (top) location to pull GOSNS/FLWR_A to BP1V5_A to configure channel A as a stack follower.
4. Install a 6.81-kΩ resistor in the R21 (Bottom) location to configure Channel A as a Phase 01 follower of a 4-pahse stack.
5. Install a 31.6-kΩ resistor in the R32 (Bottom) location to configure Channel A as a Phase 03 follower of a 4-phase stack

Connect the two boards together.

1. Add Short, Heavy Gauge wires (solid preferred) to PVIN_A, PVIN_B, VOUT_A, and VOUT_B and GND terminals on both input and output sides of board two.
   • Tighten the terminal blocks.
2. Stack Board number 1 directly on top of board number two, and connect the wires to the matching terminal blocks on board number one.
   • Tighten the terminal blocks on board number one
3. Solder the 4 small signal wires from board number one to the matching location on board number two.
   • VSHARE_A to VSHARE_A (TP12)
   • SYNC to SYNC (TP15)
   • BCX_CLK (R19) to BCX_CLK (R19)
   • BCX_DAT (R20) to BCX_CLK (R20)

The two EVMs are now configured as a single output 4-phase converter (Figure 1-1). Thanks to the BCX_CLK and BCX_DAT connections between the 4 devices, the PMBus only needs to connect to EVM board one, which is placed on top to allow access to the 10-pin connector for the USB-to-GPIO adapter.