Electronic Components Datasheet Search |
|
EM4450A5WT7 Datasheet(PDF) 10 Page - EM Microelectronic - MARIN SA |
|
EM4450A5WT7 Datasheet(HTML) 10 Page - EM Microelectronic - MARIN SA |
10 / 16 page EM4450 EM4550 Copyright 2003, EM Microelectronic-Marin SA 10 www.emmicroelectronic.com Power-On-Reset (POR) When the EM4450/4550 with its attached coil enters an electromagnetic field, the built in AC/DC converter will supply the chip. The DC voltage is monitored and a Reset signal is generated to initialise the logic. The contents of the Control word and Protection word will be downloaded to enable the functions (INIT). The Power-On-Reset is also provided in order to make sure that the chip will start issuing correct data. Hysteresis is provided to avoid improper operation at the limit level. Fig. 17 Lock All / Lock Memory Area The EM4450/4550 can be converted to a Read Only chip or be configured to Read/Write and Read Only Areas by programming the protection word. This configuration can be locked by write inhibiting the Write Protection Word. Great care should be taken in doing this operation as there is no further possibility to change the Write Protection Word. The Control Word can also be protected in the same way thus freezing the operation mode. Clock Extractor The Clock extractor will generate a system clock with a frequency corresponding to the frequency of the RF field. The system clock is used by a sequencer to generate all internal timings. Data Extractor The transceiver generated field will be amplitude modulated to transmit data to the EM4450/4550. The Data extractor demodulates the incoming signal to generate logic levels, and decodes the incoming data. Modulator The Data Modulator is driven by the serial data output from the memory which is Manchester encoded. The modulator will draw a large current from both coil terminals, thus amplitude modulating the RF field according to the memory data. AC/DC Converter and Voltage Limiter The AC/DC converter is fully integrated on chip and will extract the power from the incident RF field. The internal DC voltage will be clamped to avoid high internal DC voltage in strong RF fields. Special Timings The Processing Pause Time (tpp), Write Access Time (twa) and EEPROM Write Time (twee) are timings where the EM4450/4550 is executing internal operations. During these pauses, the RF field will be influenced. Fig. 18 t V DD t Reset V prh V prhys t init EM4450 Active During Twa and Twee, the signal on the coil is damped due to a higher current consumption. 32 32 RF periods : t pp Same modulation as for a normal bit 16 16 (Opt64) (Opt32) 64 32 (Opt64) (Opt32) t wa 3200 2624 (Opt64) (Opt32) t wee |
Similar Part No. - EM4450A5WT7 |
|
Similar Description - EM4450A5WT7 |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |