MAX16050EVKIT+ [MAXIM]
Reverse-Sequencing Operation;型号: | MAX16050EVKIT+ |
厂家: | MAXIM INTEGRATED PRODUCTS |
描述: | Reverse-Sequencing Operation |
文件: | 总13页 (文件大小:536K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
19-4199; Rev 0; 7/08
MAX16050 Evaluation Kit
Evluates:/MAX6051
General Description
Features
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.
♦ 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)
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.
♦ Daisy-Chaining Operation of the MAX16050 and
MAX16051
♦ Overvoltage and Power-Good Monitoring
♦ Fully Assembled and Tested
Ordering Information
PART
TYPE
MAX16050EVKIT+
EV Kit
+Denotes lead-free and RoHS compliant.
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.
Component List
DESIGNATION
QTY
DESCRIPTION
DESIGNATION
QTY
DESCRIPTION
Not installed, ceramic capacitors
(1206)
2200pF 5ꢀ, 50V C0G ceramic
capacitors (0805)
C1, C2, C12
0
C11, C21
2
Murata GRM2165C1H222J
Not installed, ceramic capacitors
(0805)
C3, C13
C4, C15
0
2
GND (3)
GND (2)
J1
3
2
1
1
4
PC large black test points
PC mini black test points
2 x 16 header
0.1μF 10ꢀ, 25V X7R ceramic
capacitors (0805)
Murata GRM21BR71E104K
J2
2 x 20 header
J3–J6
2-pin headers
1μF 10ꢀ, 25V X7R ceramic
capacitors (0805)
Murata GRM21BR71E105K
JU1–JU7, JU10,
JU11, JU12, JU15
C5, C14
2
9
2
11 3-pin headers
JU8, JU9, JU13,
JU14
0.01μF 10ꢀ, 25V X7R ceramic
capacitors (0805)
Murata GRM21BR71E103K
4
0
2-pin headers
C6–C9, C16-C19,
C22
Not installed, n-channel
MOSFETs (3 SOT23)
N1, N2
1200pF 5ꢀ, 50V C0G ceramic
capacitors (0805)
Murata GRM2195C1H122J
C10, C20
________________________________________________________________ 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
Component List (continued)
DESIGNATION
QTY
DESCRIPTION
DESIGNATION
QTY
DESCRIPTION
20.5kΩ 1ꢀ resistor (0805)
4-position DIP switch
OUTPUT1,
OUTPUT2,
U1_CP_OUT,
U1_EN,
R35
SW1
SW2
1
1
1
10-position DIP switch
U1_VCC, U2_VCC,
VPULLUP
U1_OV_OUT,
U1_REM,
U1_RESET,
U2_CP_OUT,
U2_EN,
U2_OV_OUT,
U2_REM,
U2_RESET
3
PC large red test points
12 PC mini red test points
4-channel voltage sequencer
(28 TQFN-EP*)
Maxim MAX16050ETI+
U1
U2
1
5-channel voltage sequencer
(28 TQFN-EP*)
1
Maxim MAX16051ETI+
R1, R12, R20, R32
4
9
86.6kΩ 1ꢀ resistors (0805)
16.5kΩ 1ꢀ resistors (0805)
—
32 Shunts (J1, J2, JU1–JU15)
PCB: MAX16050 Evaluation Kit+
R2, R4, R10, R13,
R22, R24, R30,
R33, R36
—
1
*EP = Exposed pad.
R3, R23
2
7
30.1kΩ 1ꢀ resistors (0805)
10kΩ 1ꢀ resistors (0805)
R5, R11, R14, R25,
R31, R34, R37
Component Suppliers
SUPPLIER
PHONE
WEBSITE
R6, R26
R7, R27
R8, R28
R9, R29
2
2
2
2
634kΩ 1ꢀ resistors (0805)
261kΩ 1ꢀ resistors (0805)
698kΩ 1ꢀ resistors (0805)
61.9kΩ 1ꢀ resistors (0805)
Murata
Electronics
North
770-436-1300 www.murata-northamerica.com
America, Inc.
Not installed, resistors—short
(0805)
Note: Indicate that you are using the MAX16050 or MAX16051
when contacting these component suppliers.
R15, R21
0
8
R16–R19,
R38–R41
Evluates:/MAX6051
10kΩ 5ꢀ resistor (0805)
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.
Quick Start
Required Equipment
Before beginning, the following equipment is needed:
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.
•
•
•
MAX16050 EV kit
DC power supplies: 3.5V/100mA, 5V/50mA
2-channel oscilloscope
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.
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.
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.
1) Verify that headers J1 and J2 and jumpers
JU1–JU14 are configured for demo mode configu-
ration (see Table 1).
8) Verify that both U1_RESET and U2_RESET signals
are high.
2) Verify that switches SW1 and SW2 are set to the off
position.
9) The EV kit is ready for further testing.
2
_______________________________________________________________________________________
MAX16050 Evaluation Kit
Evluates:/MAX6051
Table 1. MAX16050/MAX16051 EV Kit Jumper Description
JUMPER
SHUNT
POSITION
SIGNAL
EV kit operation
OUT_
FUNCTION
MAX16050
MAX16051
1-2*, 2-3
2-3 only
1-2
Demo mode (see Figure 1)
J1
J2
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
JU1
JU2
JU10
JU11
2-3*
1-2*
EN
2-3
1-2
Connects to CP_OUT through resistor
JU3
JU12
OUT3
Connection dependent on jumpers JU1 and JU10
configuration
2-3*
JU4
JU5
JU6
—
—
—
SEQ1
SEQ2
SEQ3
Not installed*
Not installed* Sequence order: OUT1, OUT2, OUT3, OUT4
Not installed*
1-2*
2-3
Normal operation of EN and SHDN functions
Ignores high-to-low transitions at SHDN and EN
JU7
JU15
EN_HOLD
Not installed* Controller enabled or externally driven
Controllers disabled. Reverse power-down sequencing.
RESET asserts low.
Not installed* Normal operation
Disables controller. Initiates simultaneous power-down of
JU8
JU13
SHDN
Installed
JU9
JU14
FAULT
Installed
OUT. RESET asserts low.
*Default position (demo mode operation).
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.
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.
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.
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
_______________________________________________________________________________________
3
MAX16050 Evaluation Kit
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.
Table 2. Input Channel Threshold Voltages
INPUT
THRESHOLD
VOLTAGE (V)
INPUT CHANNEL
RESISTORS
U1_IN1, U2_IN1
U1_IN2, U2_IN2
U1_IN3, U2_IN3
U1_IN4, U2_IN4
U2_IN5
3.13
2.28
1.71
1.43
1.14
R12/R13, R32/R33
R9/R10, R29/R30
R6/R7, R26/R27
R3/R4, R23/R24
R35/R36
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.
Evluates:/MAX6051
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
Evluates:/MAX6051
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
is the desired VCC undervoltage threshold,
EN
0.5V is the MAX16050/MAX16051 EN threshold voltage,
and R is the new resistor value for R1 or R20 in kilohms.
A
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.
Table 3. Jumpers JU1, JU10 Configuration
SHUNT
POSITION
OUT_ PULLUP RESISTOR VOLTAGE
SOURCE
1-2
2-3
OUT_ connects to VCC through resistor
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.
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
OUT3 PULLUP VOLTAGE
POSITION
1-2
2-3
Connects to CP_OUT through resistor
Connection dependent on jumpers JU1/JU10
configuration (see Table 3)
Table 4. Jumpers JU2, JU11 Configuration
MAX16050 Sequence Order
(JU4, JU5, JU6)
SHUNT
EN INPUT SETTING
POSITION
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.
EN connected to resistor-divider (controllers
enabled)
1-2
2-3
EN = GND (controllers disabled)
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
0.5V
⎛
⎞
⎠
EN
R
= 16.5 x
− 1
A
⎜
⎝
⎟
Table 6. MAX16050 Sequencing Control (JU4, JU5, JU6)
SHUNT POSITION
SEQUENCE ORDER
JU4
JU5
JU6
1ST
2ND
3RD
4TH
Not installed
Not installed
Not installed
Not installed
Not installed
Not installed
Not installed
Not installed
Not installed
Not installed
Not installed
U1_OUT1
U1_OUT1
U1_OUT1
U1_OUT1
U1_OUT1
U1_OUT1
U1_OUT2
U1_OUT2
U1_OUT2
U1_OUT2
U1_OUT2
U1_OUT3
U1_OUT3
U1_OUT4
U1_OUT4
U1_OUT1
U1_OUT1
U1_OUT3
U1_OUT3
U1_OUT4
U1_OUT2
U1_OUT4
U1_OUT2
U1_OUT3
U1_OUT3
U1_OUT4
U1_OUT1
U1_OUT4
U1_OUT3
U1_OUT4
U1_OUT2
U1_OUT3
U1_OUT2
U1_OUT4
U1_OUT3
U1_OUT4
Not installed
2-3
Not installed
1-2
Not installed
2-3
2-3
2-3
2-3
1-2
1-2
1-2
1-2
Not installed
2-3
1-2
_______________________________________________________________________________________
5
MAX16050 Evaluation Kit
Table 6. MAX16050 Sequencing Control (JU4, JU5, JU6) (continued)
SHUNT POSITION
SEQUENCE ORDER
JU4
2-3
2-3
2-3
2-3
2-3
2-3
2-3
2-3
2-3
1-2
1-2
1-2
1-2
1-2
1-2
JU5
Not installed
Not installed
Not installed
2-3
JU6
1ST
2ND
3RD
4TH
Not installed
U1_OUT2
U1_OUT2
U1_OUT2
U1_OUT3
U1_OUT3
U1_OUT3
U1_OUT3
U1_OUT3
U1_OUT3
U1_OUT4
U1_OUT4
U1_OUT4
U1_OUT4
U1_OUT4
U1_OUT4
U1_OUT3
U1_OUT4
U1_OUT4
U1_OUT1
U1_OUT1
U1_OUT2
U1_OUT2
U1_OUT4
U1_OUT4
U1_OUT1
U1_OUT1
U1_OUT2
U1_OUT2
U1_OUT3
U1_OUT3
U1_OUT4
U1_OUT1
U1_OUT3
U1_OUT2
U1_OUT4
U1_OUT1
U1_OUT4
U1_OUT1
U1_OUT2
U1_OUT2
U1_OUT3
U1_OUT1
U1_OUT3
U1_OUT1
U1_OUT2
U1_OUT1
U1_OUT3
U1_OUT1
U1_OUT4
U1_OUT2
U1_OUT4
U1_OUT1
U1_OUT2
U1_OUT1
U1_OUT3
U1_OUT2
U1_OUT3
U1_OUT1
U1_OUT2
U1_OUT1
2-3
1-2
Not installed
2-3
2-3
2-3
1-2
1-2
Not installed
1-2
2-3
1-2
1-2
Not installed
2-3
Not installed
Not installed
Not installed
2-3
1-2
Not installed
2-3
2-3
2-3
1-2
level at pin 1 of jumpers JU8 or JU14. Connect the sig-
nal ground to a convenient ground reference. See
Table 9 for jumpers JU9 and JU14 configuration.
EN_HOLD (JU7, JU15)
Jumpers JU7 and JU15 configuration setting allows the
MAX16050 and MAX16051 to ignore high-to-low transi-
tions at the EN and SHDN inputs. Place a shunt across
pins 1-2 for normal operation of the EN and SHDN fea-
ture. Place a shunt across pins 2-3 to ignore high-to-low
transitions at EN and SHDN. See Table 7 for jumpers
JU7 and JU15 configuration.
Table 7. Jumpers JU7, JU15 Configuration
SHUNT
EN_HOLD INPUT SETTING
POSITION
1-2
2-3
Normal operation of EN and SHDN functions
Ignores high-to-low transitions at EN and SHDN
Evluates:/MAX6051
SHDN Control (JU8, JU13)
Jumpers JU8 and JU13 initiate the MAX16050 and
MAX16051 for a reverse-sequencing event. Install
shunts on jumpers JU8 and JU13 to initiate a reverse-
sequencing event. Remove the shunts at jumpers JU8
and JU13 for proper power-up operation when EN =
high. To drive SHDN externally, place a square-wave
signal with a 2V to 5.5V logic-high level at pin 1 of
jumpers JU8 or JU13. See Table 8 for jumpers JU8 and
JU13 configuration.
Table 8. Jumpers JU8, JU13 Configuration
SHUNT
SHDN INPUT SETTING
POSITION
Not
Controller enabled or externally driven
installed
Reverse power-down sequencing. RESET
asserts low.
Installed
FAULT Control (JU9, JU14)
Jumpers JU9 and JU14 control the MAX16050 and
MAX16051 input/output FAULT signal, respectively.
FAULT asserts low when any of the monitored IN volt-
ages fall below its SET voltage threshold. As an output,
FAULT can be driven externally to initiate a simultane-
ous power-down of the DC-DC controllers. Install a
shunt across jumpers JU9 and JU14 to initiate a shut-
down of the controllers. To drive FAULT externally,
place a square-wave signal with a 2V to 5.5V logic-high
Table 9. Jumpers JU9, JU14 Configuration
SHUNT
FAULT INPUT SETTING
POSITION
Not
Normal operation
installed
Disables controller. Initiates simultaneous power
Installed
down of OUT_. RESET asserts low.
6
_______________________________________________________________________________________
MAX16050 Evaluation Kit
Evluates:/MAX6051
Sequence Delay Control
The EV kit RESET signals assert low under the following
Capacitors C10 or C20 set the t
periods for U1
conditions:
DELAY
and U2 to 644μs, respectively. Replace the capacitors
1) Any monitored voltage falls below its input threshold.
2) EN falls below the enable threshold.
3) FAULT output is pulled low.
with different values to adjust the t
remove the capacitors to set the t
periods, or
periods to
DELAY
DELAY
34μs. Use the following equation to calculate a new
capacitor value when adjusting the t period:
DELAY
− 34μs
4) SHDN is pulled low (note that when SHDN is pulled
low, the controller initiates a reverse-sequence
power-down).
t
DELAY
C =
5
5 ×10 Ω
where C is the capacitance of C10 or C20 in farads,
and t is in seconds.
DELAY
Table 10. SW2 Channel Bypass
Reset Timeout Control
Capacitors C11 and C21 set the t period for U1
SWITCH
BYPASS CHANNEL
U1_IN4
TIMEOUT
1
2
and U2 to 1.1ms, respectively. Replace the capacitors
U1_IN3
with a different value to adjust the t
periods, or
period to
TIMEOUT
3
U1_IN2
remove the capacitors to set the t
TIMEOUT
34μs. Use the following equation to calculate new
capacitor values when adjusting the t period:
4
U1_IN1
TIMEOUT
5
U2_IN5
t
− 34μs
5 x 10 Ω
TIMEOUT
6
U2_IN4
C =
5
7
U2_IN3
8
U2_IN2
where C is the capacitance of C11 or C21 in farads,
and t is in seconds.
9
U2_IN1
TIMEOUT
10
Not used
Channel Bypassing (SW2)
DIP switch SW2 allows the MAX16050 EV kit to bypass
any unused channels and to power up successfully when
using fewer than four or five DC-DC converters with the
U1_IN1–U1_IN4 and U2_IN1–U2_IN5 inputs, respectively.
To bypass a channel, remove the shunts connected
across pins 1-2 and 2-3 of headers J1 or J2, and set the
respective SW2 switch to the on position. See Table 10
for the input channel assignment on switch SW2.
Table 11. Input Overvoltage Thresholds
INPUT OVERVOLTAGE
INPUT CHANNEL
THRESHOLD (V)
_IN1
3.43
2.61
1.89
1.55
1.23
_IN2
_IN3
Logic Outputs (OV_OUT, RESET)
The MAX16050 EV kit features test points U1_OV_OUT,
U2_OV_OUT, U1_RESET, and U2_RESET to monitor
fault conditions on each controller. U1_OV_OUT and
U2_OV_OUT assert low when any of the monitored IN
voltages rise above their overvoltage threshold. See
Table 11 for the input channel overvoltage thresholds.
_IN4
IN5 (MAX16051 only)
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MAX16050 Evaluation Kit
To initiate a reverse power-down sequence, install a
shunt across jumper JU8 or JU13. When all the IN_ volt-
ages monitored by U2 (U2_IN1–U2_IN5) have dropped
below their undervoltage threshold, U2_REM output
goes high, thereby allowing U1_OUT_ to commence
sequencing down. U2_REM connects to
U1_ EN_HOLD (through SW1-2) to force U1 controller
to stay on even if U1_EN and U1_SHDN are pulled low
during a daisy-chain operation.
Configuring the MAX16050 EV Kit for
Daisy-Chain Operation (SW1)
The MAX16050 EV kit can be configured for daisy-
chain operation of the MAX16050 (U1) and the
MAX16051 (U2) by configuring DIP switch SW1 and
various jumpers. See Tables 12 and 13 for switch SW1
and the proper jumper configurations, respectively, to
configure the EV kit for daisy-chain operation. For prop-
er daisy-chain operation of U1 and U2, all of SW1
switches should be set to the on position.
Switch SW1-3 connects U1 and U2 open-drain FAULT
outputs together, resulting in a fast power-down of all
inputs when a fault condition occurs on any of the
inputs or when FAULT is manually pulled low by
installing a shunt across jumpers JU9 or JU14.
To initiate a power-up sequence, install a shunt across
pins 1-2 of jumper JU2 (U1_EN). U1_IN1–U1_IN4
sequence according to the shunt configurations of
jumpers JU4, JU5, and JU6 (Table 6). Upon U1_ inputs
rising above their respective thresholds, the U1_RESET
signal goes high and drives U2_EN input high (SW1-4)
allowing sequencing to commence on the MAX16051.
Upon U2 controller sequencing successfully,
U2_RESET goes high.
Table 12. SW1 Switch Functions
SW1
DESIGNATION
SWITCH
POSITION
EV KIT OPERATION
SHDN
On
U1 and U2 SHDN inputs connected and controlled by one signal.
Connects U2_REM to U1_EN_HOLD. Reverse-sequence U2_OUT and then U1_OUT when a
shunt is installed across jumper JU8 or JU13.
REV_SEQ
On
Connects UI_FAULT and U2_FAULT. All outputs power down simultaneously during fault
conditions.
FAULT
On
On
SEQ
Connects U1_RESET to U2_EN. Sequences U1 OUT_ and then U2 OUT_.
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Table 13. Jumper Configuration for Daisy-Chain Operation
SHUNT
POSITION
JUMPER
EV KIT OPERATION
JU2
JU7
1-2
U1 controllers enabled at U1_VCC = 3.3V (DC-DC mode)
U1_EN_HOLD controlled by U2_REM
U1_SHDN and U2_SHDN = high
Not installed
Not installed
Not installed
Not installed
1-2
JU8, JU13
JU9, JU14
JU11
U1_FAULT and U2_FAULT connected together
U2_EN controlled by switch SW1-4
JU15
U2_EN_HOLD = high
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Figure 2a. MAX16050 EV Kit Schematic (Sheet 1 of 2)
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MAX16050 Evaluation Kit
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Figure 2b. MAX16050 EV Kit Schematic (Sheet 2 of 2)
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MAX16050 Evaluation Kit
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Figure 3. MAX16050 EV Kit Component Placement Guide—Component Side
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MAX16050 Evaluation Kit
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Figure 4. MAX16050 EV Kit PCB Layout—Component Side
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MAX16050 Evaluation Kit
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Figure 5. MAX16050 EV Kit PCB Layout—Solder Side
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implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
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is a registered trademark of Maxim Integrated Products, Inc.
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