DC-DC Mode

For DC-DC mode operation, connect the DC-DC con-

verter outputs and EN/SHDN inputs to the EV kit’s IN_

and OUT_ header pins, respectively, and place shunts

across pins 2-3 of headers J1 and J2. Header J1 drives

the U1_IN1–U1_IN4 MAX16050 inputs and header J2

drives the U2_IN1–U2_IN5 MAX16051 inputs. See

Table 1 and Figure 1 for headers J1 and J2 configura-

tion for DC-DC and demo modes of operation. By

default, the input-voltage thresholds are set according

to Table 2.

The sequence delay between each of the OUT_ outputs

is the time required for the external converter voltage to

exceed the undervoltage threshold, the respective

channel open-drain output OUT_ going high imped-

ance, and the additional time delay set by external delay

capacitors C10 and C20. As each IN_ voltage meets its

respective threshold, the next OUT_ in the sequence

goes high impedance (open-drain output), enabling the

next power supply, which is then monitored by the next

input stage. When all the voltages exceed their respec-

tive thresholds, RESET goes high after the reset timeout

period set by capacitors C11 and C21.

Demo Mode

The MAX16050 EV kit allows quick evaluation of the

MAX16050 and MAX16051 ICs individually without inter-

facing DC-DC converters to the kit’s IN and OUT header

pins. Place shunts across pins 1-2 and pins 2-3 of head-

ers J1 and J2 to operate the MAX16050 EV kit in demo

mode. In demo mode, VCC or VPULLUP powers the

inputs to the respective IN_ channels with the OUT_

pullup voltage. Demo mode operation requires a mini-

mum 3.5V applied at the VCC or VPULLUP PCB input

pads. See Table 1 and Figure 1 for proper shunt place-

ment when operating the MAX16050 EV kit in demo

mode. Note that when operating the MAX16050 EV kit in

demo mode, both OV_OUT signals will be asserted low.

To daisy chain the MAX16050 and MAX16051 while

operating the EV kit in demo mode, See the

Configuring

the MAX16050 EV Kit for Daisy-Chain Operation (SW1)

section.

Input Channel Threshold Voltages (IN_)

The EV kit input-voltage thresholds are set to operate

with 3.3V, 2.5V, 1.8V, 1.5V, and 1.2V (MAX16051) volt-

age systems. All input-voltage thresholds can be recon-

figured by replacing the corresponding resistors, as

shown in Table 2. Refer to the

Resistor Value Selection

section in the MAX16050/MAX16051 IC data sheet to

calculate the new resistor values when reconfiguring

the EV kit input thresholds.

OUT_ Pullup Voltage Selection (JU1, JU10)

Jumpers JU1 and JU10 select the OUT_ open-drain

pullup voltage. Place a shunt across pins 1-2 of

jumpers JU1 and JU10 to select the respective power-

supply inputs (U1_VCC, U2_VCC) as the OUT_ logic-

high voltage. Place shunts across pins 2-3 of jumpers

JU1 and JU10 to select VPULLUP as the OUT_ logic-

high voltage. See Table 3 for proper jumper settings for

OUT_’s logic-high voltage configuration.

MAX16050 Evaluation Kit

4

_______________________________________________________________________________________

Table 2. Input Channel Threshold Voltages

INPUT CHANNEL

INPUT

THRESHOLD

VOLTAGE (V)

RESISTORS

U1_IN1, U2_IN1

3.13

R12/R13, R32/R33

U1_IN2, U2_IN2

2.28

R9/R10, R29/R30

U1_IN3, U2_IN3

1.71

R6/R7, R26/R27

U1_IN4, U2_IN4

1.43

R3/R4, R23/R24

U2_IN5

1.14

R35/R36

Figure 1. Headers J1/J2 Shunt Configurations for DC-DC and

Demo Mode Operation