User's Guide for the LMZM23601 and LMZM23600
Evaluation Boards
The evaluation modules (EVM) for the LMZM23601 and LMZM23600 are designed as easy-to-use
platforms to help evaluate the features and performance of these DC/DC step-down power modules. This
guide provides an overview of the board settings and board layout along with connection diagrams and
several performance curves for each device in the family.
18Output Ripple for V
19Output Ripple for V
20Efficiency for V
21Load Transient Response for V
22Output Ripple for V
23Output Ripple for V
24Efficiency for V
25Load Transient Response for V
26Output Ripple for V
27Output Ripple for V
The LMZM23601 and LMZM23600 are miniature, simple, and easy-to-use DC/DC converter modules ideal
for applications where board space is limited and an efficient power conversion is needed. Both the
LMZM23600 and the LMZM23601 support an input range of 4 V to 36 V. This range makes the modules
suitable to be powered from various 5-V, 12-V, or 24-V supplies. The LMZM23600 supports load current
of up to 0.5 A, and the LMZM23601 can deliver up to 1 A of current. Features of the devices include a
precision enable circuit, input UVLO circuit, built-in soft start, light load mode selection for exceptional
power savings or constant frequency operation, switching frequency synchronization to an external clock,
power-good flag, and current limit protection. More details about the operating range, features, and
specifications of the LMZM23601 and LMZM23600 can be found in the device data sheet.
The output voltage for the adjustable (ADJ) version can be configured between 2.5 V and 15 V. There are
also fixed output options of the devices for 5-V and 3.3-V outputs and each voltage option comes in two
output current choices: 0.5 A and 1 A. There are two main evaluation boards - one for the ADJ output
voltage options and one for the fixed 5-V and 3.3-V outputs. The ADJ output board comes in two variants,
one for the 1-A capable devices and one for the 0.5-A current option. The fixed output voltage option
boards also come in two output current variations. Table 1 summarizes the available evaluation boards for
this module family.
Description
Table 1. Available Evaluation Boards
Output Voltage
ADJ (2.5 V to 15 V)1 ALMZM23601LMZM23601EVMBSR017-001
ADJ (2.5 V to 15 V)0.5 ALMZM23600LMZM23600EVMBSR017-002
Figure 3. Jumper Configuration Details for Each Board
Before applying power to the EVM, ensure that all of the jumpers are in place and are properly positioned
for the intended feature setting and output voltage operation. Always shut down the input power supply
before changing any of the jumper settings. Figure 1 and Figure 3 above provide an overview of the board
connection terminals, jumper setting options, and test points.
Use the "VIN POWER TERMINAL" and "GND TERMINAL" turrets to connect the board to the input
supply. Connect the load between the "VOUT TERMINAL" and "GND TERMINAL".
For the adjustable output version of the board, the output voltage setting jumper configures the feedback
resistor divider pair for various popular output voltages: 2.5 V, 3.3 V, 5 V, 12 V, or 15 V. Voltage sense
points are provided to help read the input voltage and output voltage directly at the regulator. The sense
lines should not be used for power connections. There are several test points provided on the left hand
side of the board. They can be used to monitor the voltage signals at the MODE, EN, and PG pins of the
device.
The EN selection jumper allows the user to select the desired enabling scheme for the end application.
The LMZM23600 and LMZM23601 feature a precision enable input which can be used to set the input
UVLO point with a voltage divider from the input voltage. Alternatively, the enable input can be driven by a
logic signal or it could be tied directly to VIN for an always-on operation.
The MODE selection jumper sets the DC/DC converter mode of operation at light load. When Auto PFM
mode is selected, the converter will enter PFM mode at light load and reduce the switching frequency in
order to maintain high conversion efficiency. Some applications may require that the regulator maintains
constant switching frequency across the entire load range. In such cases the mode pin can be used to set
forced PWM operation at light load. The mode terminal can also be used to synchronize the converter
switching frequency to an external clock. If frequency synchronization is used, the converter will operate in
forced PWM mode at light load.
The PGOOD flag jumper allows the user to either connect the PGOOD pullup resistor to VOUT or provide
an external voltage rail for the logic HIGH voltage level.