Analog Devices MAX77857, Руководство пользователя

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Evaluates: MAX77857 (WLP) MAX77857 Evaluation Kit
www.analog.com Analog Devices | 3
EV Kit Default Configuration
With the default jumper settings listed in Table 1 and the EV kit component values of R
SEL
(R9) = 0 Ω, R
TOP
(R10) =
0Ω,
and R
BOT
(R11) = OPEN, the MAX77857 EV kit is configured with the following settings:
•
Internal Feedback
•
Switching Current Limit = 7A
•
I
2
C Slave Address (7-bit) = 0x66
•
Switching Frequency = 1.8MHz (adjustable only through I
2
C)
•
V
IO
Disconnected from V
L
•
EN Controlled from V
IO
(as opposed to controlled from V
IN
)
See the EV Kit Hardware section to change the EV kit configuration.
Table 1. Default Shunt Positions and Jumper Descriptions
JUMPER NODE
SHUNT
POSITION
FUNCTION
J1 EN
1-2*
Connects EN to V
IN
through a 510k
Ω
pullup resistor for standalone operation.
See the Standalone Operation section for more information.
2-3
Connects EN to V
IO
. The converter is enabled when both V
IN
and V
IO
are valid.
Not installed
Floats EN. Use for controlling EN from an external logic signal. The converter is
disabled if no external logic signal is connected to EN.
J2
V
IO
1-2*
Connects V
IO
to V
L
. Allow V
IO
to be powered from V
L
without the need for a
separate V
IO
supply. See the Standalone Operation section for more
information.
Not installed
Disconnects V
IO
from VL. V
IO
needs to be powered from either
MAXUSB_INTERFACE# or an external V
IO
supply.
*Default position
Quick Start
Required Equipment
•
MAX77857 EV Kit
•
Adjustable DC power supply
•
Digital multi-meters
•
Electronic load
•
MAXUSB_INTERFACE# for I
2
C serial interface (optional)
•
USB Type-A to Micro-USB cable (optional)
•
Windows-based PC with MAX77857 EV kit GUI (optional)
Setup Overview
Typical bench setups for the MAX77857 EV kit with different configurations are shown in Figure 3 , Figure 4 , and Figure
5 .