1 Introduction
The TPSM82866AA0SRDJR and TPSM82864AA0SRDJR are synchronous, step-down converter power
modules in a small 3.5-mm × 4-mm overmolded QFN package with 1.4-mm height. The
TPSM82866AA0HRDMR and TPSM82864AA0HRDMR are synchronous, step-down converter power modules
in a small 3.5-mm × 4-mm overmolded QFN package with 1.8-mm height. The four devices in this family support
4-A or 6-A output currents.
1.1 Performance Specification
provides a summary of the TPSM8286xAA0xEVM performance specifications.
Table 1-1. Performance Specification Summary
SPECIFICATION
TEST CONDITIONS
MIN
TYP
MAX
UNIT
Input voltage
2.4
5
5.5
V
Output voltage setpoint
1.2
V
Output current
TPSM82866AA0SEVM (BSR182-001)
0
6
A
TPSM82864AA0SEVM (BSR182-002)
0
4
TPSM82866AA0HEVM (BSR182-003)
0
6
TPSM82864AA0HEVM (BSR182-004)
0
4
1.2 Modifications
The printed-circuit board (PCB) for this EVM is designed to accommodate some modifications by the user.
Additional input and output capacitors or a feedforward capacitor can be added. Also, the MODE setting and
output voltage setting configuration can be changed. Finally, the loop response can be measured.
1.2.1 Input and Output Capacitors
C9, shown in
, is provided for an additional input capacitor. This capacitor is not required for proper
operation, but can be used to reduce the input voltage ripple.
C5, C6, C7, and C8 are provided for additional output capacitors. These capacitors are not required for proper
operation but can be used to reduce the output voltage ripple and to improve the load transient response. The
total output capacitance must remain within the recommended range in the data sheet for proper operation.
1.2.2 Feedforward Capacitor
C4 is provided as an optional feedforward capacitor (C
FF
).
1.2.3 VSET/MODE Resistor
R4 selects the MODE setting (PSM or FPWM) and output voltage setting configuration. When using the VSET
configuration for setting the output voltage, short R1 and remove R2. See the
Efficiency Step-Down Converter QFN Power Module data sheet
for details of the various settings.
1.2.4 Loop Response Measurement
The loop response can be measured with simple changes to the circuitry. First, install a 10-Ω resistor across the
pads of R6 on the back of the PCB. The pads are spaced to allow installation of an 0603-sized resistor. Next, cut
the short section of trace on the top layer between the via near R1 and the V
OUT
plane.
shows this
change. With these changes, an AC signal (10-mV, peak-to-peak amplitude recommended) can be injected into
the control loop across the added 10-Ω resistor.
shows the results of this test.
Introduction
2
TPSM8286xAA0xEVM Evaluation Module
SLVUCB0A – SEPTEMBER 2021 – REVISED NOVEMBER 2022
Copyright © 2022 Texas Instruments Incorporated