Datasheet

NXP Semiconductors

FRDM33771BTPLEVB

Featuring the MC33771B battery cell controller IC

User guide Rev. 1.0 — 28 June 2018

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After a reset, the EEPROM is not enabled. When the EEPROM is enabled, the device

can load the EEPROM calibration parameters into the MC33771B registers.

4.10 GPIO configuration

The FRDM33771BTPLEVB offers seven customizable GPIOs [GPIO_0...GPIO_6] for

measuring external temperature with on-board or off-board NTCs. The off-board NTC

connection is described in Section 6.5 "Off-board NTC configuration ".

4.11 Cell terminal voltage measurement

The differential measurement of each cell terminal input is designed to function in

conjunction with an external anti-aliasing filter with a corner frequency.

4.12 Fault detection

The FRDM33771BTPLEVB uses an optocoupler to detect a fault that is dependent on

user defined internal or external faults.

The fault signal can be chained between EVBs and can be made available on the

controller inputs. With two FRDM33771BTPLEVB boards, the fault is chained as shown

in Section 6.4 "Fault chain connection".

4.13 Current sensing

The FRDM33771BTPLEVB supports current sense function with off-board shunt resistor.

The off-board shunt resistor shall be connected between J26-31 (ISENSE+) and J26-32

(ISENSE–). On-board current sensing filter and protection circuits can be found in EVB

schematic shared via NXP DocStore (NDA required).

4.14 Bus terminal communication

The transformers isolate communication between the MC33771B and the pack controller

and between each MC33771B. They are protected against ESD. There are significant

advantages to using transformers for isolation and communication:

• High degree of voltage isolation

• Communication rates of 2.0 MHz with very low radiated emissions

• Ability to force the secondary signals to be true differential reducing radiated emissions

• Ability to loop the network back to the pack controller

Detailed schematic, component selection, and layout recommendations can be obtained

from the NXP DocStore (NDA required). [6]

5 Accessory transceiver board

The FRDM33771BTPLEVB kit is designed for use with the FRDM33664BEVB in high-

voltage isolated applications that provide a SPI-to-high-speed isolated communication

interface. The FRDM33664BEVB includes an MC33664 isolated network high-speed

transceiver. MCU SPI data bits are directly converted to pulse bit information.