1 Introduction
The TPS62843x is a family of synchronous, step-down converters in a 0.8-mm × 1.05-mm wafer chip-scale
package (WCSP) with a 0.4-mm pitch. The BSR167 EVM contains three completely independent circuits, each
for a different IC version. See
for a summary of the BSR167 EVMs.
The reference designator order is grouped by sub-circuit. Reference designators beginning with
1
(for example,
R1x, J1x, C1x) are part of one sub-circuit. The second digit of each reference designator is the same for the
same component in different sub-circuits. R11, R21, and R31, for example, refer to the same resistor in each
sub-circuit.
Table 1-1. BSR167 Circuit Options
EVM Version
IC Installed
Output Voltage Setpoint
Output Voltage
Setpoint Range
Output Current
TPS628436-7-8EVM167
(BSR167-001)
TPS628436 (U11)
0.6 V
0.4-0.8 V (adjustable)
600 mA
TPS628437 (U21)
0.9 V
0.8-1.8 V (adjustable)
600 mA
TPS628438 (U31)
1.8 V
1.8-3.6 V (adjustable)
600 mA
1.1 Performance Specification
provides a summary of the TPS628436-7-8EVM-167 performance specifications.
Table 1-2. Performance Specification Summary
SPECIFICATION
MIN
TYP
MAX
UNIT
Input voltage
1.8
3.6
5.5
V
Output voltage setpoint
V
Output current
0
mA
1.2 Modifications
The printed circuit board (PCB) for this EVM is designed to accommodate all the output voltage versions of this
integrated circuit (IC). Extra input and output capacitors can also be added. Finally, the loop response of the IC
can be measured by configuring the board.
1.2.1 Adjusting the Output Voltage
The output voltage can be adjusted through the choice of Rx1 and Rx2 resistors. Since Rx1 and Rx2 are in
parallel, only Rx1 or Rx2 should be installed one at a time. Rx1 is an 0201 size to represent a typical solution in
actual application. However, such a small size is difficult to replace. Therefore, Rx2 is provided in an 0603 size to
change the output voltage easily. Simply remove Rx1 and place the desired value to Rx2.
1.2.2 Input and Output Capacitors
Cx2 provides an additional input capacitor. This capacitor is not required for proper operation but can be used to
reduce the input voltage ripple.
Cx5, Cx6, and Cx7 are options for additional output capacitors. These capacitors are not mandatory for the
device's proper operation. But it can be used to reduce the output voltage ripple and improve the load transient
response. The total output capacitance must remain within the recommended range in the data sheet for proper
operation.
1.2.3 Loop Response Measurement
The loop response of the EVM can be measured with two simple changes to the circuitry. First, cut the trace
between the VOS pin and the output capacitor on the top layer. This change is shown in
place a 10-Ω resistor across the resistor pads on the back of the PCB at Rx3. The pads are spaced to
allow installation of an 0603-sized resistor. With these changes, an ac signal (100-mV, peak-to-peak amplitude
recommended) can be injected into the control loop across the added resistor. Details of measuring the control
loop of DCS-Control devices are found in
How to Measure the Control Loop of DCS-Control™ Devices
Introduction
2
TPS628436-7-8EVM-167 Evaluation Module
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