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Evaluates: MAX38802

MAX38802 Evaluation Kit

Input Voltage Monitoring

VDD1 and GND1 sense points as well as J3 can be used

to monitor the input supply.

Output Voltage Monitoring

J11 and J13 monitor the output voltage. These test points

should not be used for loading. Use scopejack J14 to

monitor the output voltage ripple on an oscilloscope.

Efficiency Measurement

The following steps describe how to measure the regula-

tor efficiency.

1) Connect a 12V power supply to the VDD1 and GND1

banana jacks. To avoid the input voltage to drop at

high load due to power losses on connection cables

connect the sense lines of the power supply to VDD1

and GND1 headers.

2) Connect an external 1.8V, 0.1A current limited power

supply between J12-2 and ground

3) Connect the same power supply to J10-1 to enable

the regulator.

4) Connect a load to the VOUT and GND banana jacks

for better results. J8 can also be used for low currents.

5) Make sure the shunt is installed on J16 (1-2) to close

the sense line.

6) Remove all the other jumpers.

7) Connect a voltmeter to J11 or J13

8) Turn on the power supply.

10) Calculate the efficiency as:

Equation 3

(

)

(

)

OUT

OUT

IN

IN

BIAS

BIAS

VI

VI

V

I



×

η= 



×+

×



R_SEL

C_SEL

VCCVDDH

STAT

OE

AGND

PGM

GND

SENSE-

SENSE+

VX

BST

MAX38802

Kelvin Connection to Load

Figure 1. Electrical Connections to Use the External Voltage Reference Feature