19-4199; Rev 0; 7/08
MAX16050 Evaluation Kit
General Description
The MAX16050 evaluation kit (EV kit) is a complete, fully
assembled and tested multivoltage sequencer circuit that
demonstrates the capability of the 4-channel MAX16050
and 5-channel MAX16051 sequencing ICs. The
MAX16050 EV kit monitors up to nine DC-DC converter
outputs and ensures proper power-up and power-down
conditions for systems requiring voltage sequencing.
The EV kit features
RESET
output signals to indicate an
undervoltage condition, or when
SHDN
or
FAULT
sig-
nals are pulled low. Additionally, dedicated
OV_OUT
outputs indicate an overvoltage fault when any of the
EV kit’s inputs go above the overvoltage threshold. The
EV kit is capable of evaluating the MAX16050 and
MAX16051 individually. The EV kit can be configured
for daisy chaining these two devices together, which
enables the user to sequence and monitor up to nine
voltages across both devices. The MAX16050 EV kit
also provides PCB pads for low-current MOSFETs that
are controlled using the MAX16050 and MAX16051
charge-pump outputs.
The MAX16050 EV kit utilizes two power supplies, one
for each IC. Each power supply can range from 2.7V to
13.2V, allowing the user to operate directly from an
intermediate bus voltage. The MAX16050 EV kit also
requires an additional 2.2V to 5.5V power supply for the
pullup resistors’ open-drain logic outputs.
Features
♦
Quick Demo Mode Evaluation Without DC-DC
Converters
♦
Monitors and Sequences Up to Nine DC-DC
Converter Outputs
♦
Reverse-Sequencing Operation
♦
Configurable Sequencing Order (MAX16050 Only)
♦
Daisy-Chaining Operation of the MAX16050 and
MAX16051
♦
Overvoltage and Power-Good Monitoring
♦
Fully Assembled and Tested
Evaluates: MAX16050/MAX16051
Ordering Information
PART
MAX16050EVKIT+
TYPE
EV Kit
+Denotes
lead-free and RoHS compliant.
Component List
DESIGNATION
C1, C2, C12
C3, C13
QTY
0
0
DESCRIPTION
Not installed, ceramic capacitors
(1206)
Not installed, ceramic capacitors
(0805)
0.1μF ±10%, 25V X7R ceramic
capacitors (0805)
Murata GRM21BR71E104K
1μF ±10%, 25V X7R ceramic
capacitors (0805)
Murata GRM21BR71E105K
0.01μF ±10%, 25V X7R ceramic
capacitors (0805)
Murata GRM21BR71E103K
1200pF ±5%, 50V C0G ceramic
capacitors (0805)
Murata GRM2195C1H122J
DESIGNATION
C11, C21
GND (3)
GND (2)
J1
J2
J3–J6
JU1–JU7, JU10,
JU11, JU12, JU15
JU8, JU9, JU13,
JU14
N1, N2
QTY
2
3
2
1
1
4
11
4
0
DESCRIPTION
2200pF ±5%, 50V C0G ceramic
capacitors (0805)
Murata GRM2165C1H222J
PC large black test points
PC mini black test points
2 x 16 header
2 x 20 header
2-pin headers
3-pin headers
2-pin headers
Not installed, n-channel
MOSFETs (3 SOT23)
C4, C15
2
C5, C14
2
C6–C9, C16-C19,
C22
9
C10, C20
2
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
MAX16050 Evaluation Kit
Evaluates: MAX16050/MAX16051
Component List (continued)
DESIGNATION
OUTPUT1,
OUTPUT2,
U1_CP_OUT,
U1_EN,
U1_OV_OUT,
U1_REM,
U1_RESET,
U2_CP_OUT,
U2_EN,
U2_OV_OUT,
U2_REM,
U2_RESET
R1, R12, R20, R32
R2, R4, R10, R13,
R22, R24, R30,
R33, R36
R3, R23
R5, R11, R14, R25,
R31, R34, R37
R6, R26
R7, R27
R8, R28
R9, R29
R15, R21
R16–R19,
R38–R41
QTY
DESCRIPTION
DESIGNATION
R35
SW1
SW2
U1_VCC, U2_VCC,
VPULLUP
U1
QTY
1
1
1
3
DESCRIPTION
20.5kΩ ±1% resistor (0805)
4-position DIP switch
10-position DIP switch
PC large red test points
4-channel voltage sequencer
(28 TQFN-EP*)
Maxim MAX16050ETI+
5-channel voltage sequencer
(28 TQFN-EP*)
Maxim MAX16051ETI+
Shunts (J1, J2, JU1–JU15)
PCB: MAX16050 Evaluation Kit+
12
PC mini red test points
1
U2
4
9
2
7
2
2
2
2
0
8
86.6kΩ ±1% resistors (0805)
—
16.5kΩ ±1% resistors (0805)
30.1kΩ ±1% resistors (0805)
10kΩ ±1% resistors (0805)
634kΩ ±1% resistors (0805)
261kΩ ±1% resistors (0805)
698kΩ ±1% resistors (0805)
61.9kΩ ±1% resistors (0805)
Not installed, resistors—short
(0805)
10kΩ ±5% resistor (0805)
SUPPLIER
Murata
Electronics
North
America, Inc.
—
1
32
1
*EP = Exposed pad.
Component Suppliers
PHONE
WEBSITE
770-436-1300 www.murata-northamerica.com
Note:
Indicate that you are using the MAX16050 or MAX16051
when contacting these component suppliers.
Quick Start
Required Equipment
Before beginning, the following equipment is needed:
• MAX16050 EV kit
• DC power supplies: 3.5V/100mA, 5V/50mA
• 2-channel oscilloscope
3) Connect the positive terminal of the 3.5V power
supply to the U1_VCC and U2_VCC test points.
Connect the ground terminal of this power supply to
the respective GND test points.
4) Connect the positive terminal of a 5V power supply
to the VPULLUP test point. Connect the ground ter-
minal of this power supply to the GND test point.
5) Connect oscilloscope channels 1 and 2 to the
U1_RESET and U2_RESET test points, respectively.
Connect the ground leads to the nearby black GND
test points.
6) Turn on the VCC power supply and adjust the volt-
age to 3.5V.
7) Turn on the VPULLUP power supply and adjust the
voltage to 5V.
8) Verify that both U1_RESET and U2_RESET signals
are high.
9) The EV kit is ready for further testing.
Procedure
The MAX16050 EV kit is a fully assembled and tested
surface-mount board. Follow the steps below to verify
board operation.
Caution: Do not turn on the power
supplies until all connections are completed.
1) Verify that headers J1 and J2 and jumpers
JU1–JU14 are configured for demo mode configu-
ration (see Table 1).
2) Verify that switches SW1 and SW2 are set to the off
position.
2
_______________________________________________________________________________________
MAX16050 Evaluation Kit
Evaluates: MAX16050/MAX16051
Table 1. MAX16050/MAX16051 EV Kit Jumper Description
JUMPER
MAX16050
J1
JU1
JU2
MAX16051
J2
JU10
JU11
SIGNAL
EV kit operation
OUT_
EN
SHUNT
POSITION
1-2*, 2-3
2-3 only
1-2
2-3*
1-2*
2-3
1-2
JU3
JU4
JU5
JU6
JU7
JU12
—
—
—
JU15
OUT3
SEQ1
SEQ2
SEQ3
EN_HOLD
2-3*
Not installed*
Not installed*
Not installed*
1-2*
2-3
Not installed*
JU8
JU13
SHDN
Installed
Not installed*
JU9
JU14
FAULT
Installed
Normal operation of EN and
SHDN
functions
Ignores high-to-low transitions at
SHDN
and EN
Controller enabled or externally driven
Controllers disabled. Reverse power-down sequencing.
RESET
asserts low.
Normal operation
Disables controller. Initiates simultaneous power-down of
OUT.
RESET
asserts low.
Sequence order: OUT1, OUT2, OUT3, OUT4
FUNCTION
Demo mode (see Figure 1)
DC-DC mode (see Figure 1)
OUT_ connects to VCC through resistor
OUT_ connects to VPULLUP through resistor
Controllers enabled at U1_VCC/U2_VCC > 3.2V
Controllers disabled
Connects to CP_OUT through resistor
Connection dependent on jumpers JU1 and JU10
configuration
*Default position (demo mode operation).
Detailed Description of Hardware
The MAX16050 evaluation kit (EV kit) evaluates the 4-
channel MAX16050 and 5-channel MAX16051 power-
supply sequencing ICs. The MAX16050 EV kit monitors
up to nine DC-DC converter outputs, thus ensuring
proper power-up and power-down conditions for sys-
tems requiring voltage sequencing. During power-
down, the outputs can be reverse-sequenced by
driving
SHDN
low. The MAX16050 EV kit’s VCC power-
supply inputs require 2.7V to 13.2V and VPULLUP
requires 2.2V to 5.5V.
The MAX16050 EV kit can operate in DC-DC mode or in
demo mode. DC-DC mode uses the MAX16050 and
MAX16051 to control external DC-DC converters, and
without demo mode facilitates stand-alone evaluation
without external DC-DC converters.
The EV kit features
RESET
output signals to indicate an
undervoltage condition, or when shunts are installed
across the jumpers labeled
SHDN
or
FAULT.
Additionally, dedicated
OV_OUT
outputs indicate over-
voltage faults when any of the monitored EV kit IN inputs
go above their overvoltage thresholds. The EV kit also
provides test points OUTPUT1 and OUTPUT2 for low-cur-
rent n-channel MOSFETs N1 and N2, respectively, which
are controlled by the MAX16050 and MAX16051 charge-
pump outputs. Refer to the MAX16050/MAX16051 IC
data sheet for additional information on selecting appro-
priate MOSFETs when driving external MOSFETs using
the charge-pump outputs.
Power-Supply Connections
(U1_VCC, U2_VCC, VPULLUP)
The MAX16050 EV kit requires input voltages of 2.7V to
13.2V connected at the U1_VCC and U2_VCC test
points to power the MAX16050 and MAX16051 con-
trollers, respectively. The power supplies must provide
at least 50mA of current. VPULLUP requires an input
voltage of 2.2V to 5.5V connected to the VPULLUP test
point and supplies power to the EV kit’s pullup resistor
open-drain outputs. The VPULLUP power supply must
provide at least 50mA of current. Additional surface-
mount 1206 PCB pads are provided for adding addition-
al bulk capacitance at C1, C2, and C12 for the EV kit
power-supply inputs. Header pins J3–J6 are available to
use as ground reference for signal and voltage probing.
3
_______________________________________________________________________________________
MAX16050 Evaluation Kit
Evaluates: MAX16050/MAX16051
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.
Table 2. Input Channel Threshold Voltages
INPUT CHANNEL
U1_IN1, U2_IN1
U1_IN2, U2_IN2
U1_IN3, U2_IN3
U1_IN4, U2_IN4
U2_IN5
INPUT
THRESHOLD
VOLTAGE (V)
3.13
2.28
1.71
1.43
1.14
RESISTORS
R12/R13, R32/R33
R9/R10, R29/R30
R6/R7, R26/R27
R3/R4, R23/R24
R35/R36
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.
Figure 1. Headers J1/J2 Shunt Configurations for DC-DC and
Demo Mode Operation
4
_______________________________________________________________________________________
MAX16050 Evaluation Kit
Caution:
When operating the MAX16050 EV kit
U1_VCC or U2_VCC inputs with power supplies greater
than 5.5V, verify that shunts are installed across pins 2-3
of jumpers JU1 and JU10 to prevent operating the open-
drain logic outputs above the maximum voltage rating.
where V
EN
is the desired VCC undervoltage threshold,
0.5V is the MAX16050/MAX16051 EN threshold voltage,
and R
A
is the new resistor value for R1 or R20 in kilohms.
Evaluates: MAX16050/MAX16051
Charge-Pump Outputs (CP_OUT)
The EV kit features test points (U1_CP_OUT,
U2_CP_OUT) to monitor the MAX16050 and MAX16051
charge-pump outputs. PCB pads are also available for
the installation of low-current SOT23 footprint n-channel
MOSFETs at N1 and N2.
The EV kit’s charge-pump outputs can also be used as
the pullup voltages for open-drain output OUT3 using
jumpers JU3 and JU12. See Table 5 for configuring
OUT3 to the respective charge-pump outputs.
Table 3. Jumpers JU1, JU10 Configuration
SHUNT
POSITION
1-2
2-3
OUT_ PULLUP RESISTOR VOLTAGE
SOURCE
OUT_ connects to VCC through resistor
OUT_ connects to VPULLUP through resistor
EN Control (JU2, JU11)
Jumpers JU2 and JU11 enable or disable the MAX16050
and MAX16051, respectively, for power-up sequencing
and simultaneous power-down operation. Install shunts
across pins 1-2 of jumpers JU2 and JU11 to initiate a
power-up sequence. Install a shunt across pins 2-3 to
power down the channels and to assert
RESET.
See
Table 4 for jumpers JU2 and JU11 configuration.
Table 5. Jumpers JU3, JU12 Configuration
SHUNT
POSITION
1-2
2-3
OUT3 PULLUP VOLTAGE
Connects to CP_OUT through resistor
Connection dependent on jumpers JU1/JU10
configuration (see Table 3)
Table 4. Jumpers JU2, JU11 Configuration
SHUNT
POSITION
1-2
2-3
EN INPUT SETTING
EN connected to resistor-divider (controllers
enabled)
EN = GND (controllers disabled)
MAX16050 Sequence Order
(JU4, JU5, JU6)
Jumpers JU4, JU5, and JU6 configure the MAX16050
sequencing order. The jumper settings allow up to 24
different power-up combinations. The MAX16051 does
not feature programmable power-supply sequencing
and powers up in a fixed order from U2_OUT1–U2_
OUT5. See Table 6 to configure the sequencing order
for U1_OUT1–U1_OUT4.
The voltage threshold of each analog EN input is config-
ured to 3.17V using resistors R1/R2 (U1) and R20/R22
(U2). Use the following equation to calculate a new R1 or
R20 resistor value to change the enable threshold:
⎛
V
⎞
R
A
=
16. 5 x
⎜
EN
−
1
⎟
⎝
0 . 5V
⎠
Table 6. MAX16050 Sequencing Control (JU4, JU5, JU6)
SHUNT POSITION
JU4
Not installed
Not installed
Not installed
Not installed
Not installed
Not installed
Not installed
Not installed
Not installed
JU5
Not installed
Not installed
Not installed
2-3
2-3
2-3
1-2
1-2
1-2
JU6
Not installed
2-3
1-2
Not installed
2-3
1-2
Not installed
2-3
1-2
1ST
U1_OUT1
U1_OUT1
U1_OUT1
U1_OUT1
U1_OUT1
U1_OUT1
U1_OUT2
U1_OUT2
U1_OUT2
SEQUENCE ORDER
2ND
U1_OUT2
U1_OUT2
U1_OUT3
U1_OUT3
U1_OUT4
U1_OUT4
U1_OUT1
U1_OUT1
U1_OUT3
3RD
U1_OUT3
U1_OUT4
U1_OUT2
U1_OUT4
U1_OUT2
U1_OUT3
U1_OUT3
U1_OUT4
U1_OUT1
4TH
U1_OUT4
U1_OUT3
U1_OUT4
U1_OUT2
U1_OUT3
U1_OUT2
U1_OUT4
U1_OUT3
U1_OUT4
_______________________________________________________________________________________
5