SLVSGG8E November 2023 – October 2025 TPS6287B10 , TPS6287B15 , TPS6287B20 , TPS6287B25 , TPS6287B30
PRODUCTION DATA
The device can control the inductor current in three different ways to regulate the output:
During PWM-CCM operation, the device switches at a constant frequency and the inductor current is continuous (see Figure 8-2). PWM operation achieves the lowest output voltage ripple and the best transient performance.
During PWM-DCM operation the device switches at a constant frequency and the inductor current is discontinuous (see Figure 8-3). In this mode the device controls the peak inductor current to maintain the selected switching frequency while still being able to regulate the output.
During PFM-DCM operation the device keeps the peak inductor current constant (at a level corresponding to the minimum on-time of the converter) and skips pulses to regulate the output (see Figure 8-4). The switching pulses that occur during PFM-DCM operation are synchronized to the internal clock.
.Use Equation 1 to calculate the output current threshold at which the device enters PFM-DCM:
The following figure shows how this threshold typically varies with VIN and VOUT for a switching frequency of 1.5MHz.
Configure the device to use either Forced-PWM (FPWM) mode or Power-Save Mode (PSM):
Table 8-1 shows the function table of the MODE/SYNC pin and the FPWMEN bit in the CONTROL1 register, which control the operating mode of the device.
| MODE/SYNC Pin | FPWMEN Bit | Operating Mode | Remark |
|---|---|---|---|
| Low | 0 | PSM | Do not use in a stacked configuration |
| 1 | FPWM | ||
| High | X | FPWM | |
| Sync Clock | X | FPWM |