Lattice Semiconductor ispMACH 4000ZE Pico, Руководство пользователя

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ispMACH 4000ZE Pico Development Kit
Lattice Semiconductor User’s Guide
Figure 8. ispMACH 4000ZE Pico Evaluation Board Block Diagram
ispMACH4256ZE-
MN144
4-bit DIP
Switch
ispPAC-
POWR6AT6
2
2X16
Header
3-char 7-seg
LCD
GPIO 10
USB
Controller
USB Mini-B
Socket
A/Mini-B
USB Cable
JTAG
Programming
14
I
2
C
I
2
C
4
Current
Sense Circuit
2
Table 4 describes the components on the board and the interfaces it supports.
Table 4. Pico Evaluation Board Components and Interfaces
Component/Interface Type Schematic Reference Description
Circuits
Power Circuit Circuit Figure 11
5V USB, 3V battery, and optional lithium-ion
20mA charge circuit.
High-Side Current Sense
Circuit
Circuit Figure 13
Resistive current sensor circuit to produce a
voltage level proportional to the current level
(see AN6049,
High-side Current Sensing
Techniques for Power Manager Devices ).
USB Controller Circuit U4:FT2232D
USB-to-JTAG interface and dual USB
UART/FIFO IC.
USB Mini B Socket I/O J1:USB_MINI_B Programming and debug interface.
Components
LC4256ZE CPLD U1: Lattice_4kZE
256-macrocell CPLD packaged in a 7 x 7mm,
144-ball chip-scale BGA.
POWR6AT6 Mixed Signal PLD U6: ispPAC-POWR6AT6
Integrates analog DC-to-DC trim outputs,
analog monitor, power supply margin/trim
control, ADC, and I
2
C interface in a 32-ball
QFNS package.
Interfaces
LCD Panel Output U2: LUMEX-LCD2 3-character, 7-segment LCD panel.
15x2 Header Landing I/O J2:HEADER 15X2 User-definable I/O.
4-Bit DIP Switch Input SW2: SWDIP-4 General purpose 4-bit DIP switch.
Push-button Switch Input SW1:GlobalReset General purpose push-button.
Subsystems
This section describes the principle subsystems for the Pico board in alphabetical order.
Battery
A CR2032 watch cell battery provides a 3V supply rail for a portion of the Pico board and covers the LC4256ZE,
current sensor circuit, and LCD power requirements. As a power saving measure a power MOSFET circuit enables
the sensor circuit only upon measurement requests by the CPLD.
The Pico board can be populated by the user with a 20mA charger circuit for use with Li-Ion rechargable batteries
only. Do not try to recharge a standard CR2032 battery.