Electronic Components Datasheet Search |
|
MIC2558 Datasheet(PDF) 5 Page - Micrel Semiconductor |
|
MIC2558 Datasheet(HTML) 5 Page - Micrel Semiconductor |
5 / 6 page MIC2558 Micrel 2-14 1997 Applications Information PCMCIA VPP1 and VPP2 control is easily accomplished using the MIC2558 voltage selector/switch IC. Two control bits per VPP OUT pin determine output voltage and standby/ operate mode condition. Output voltages of 0V (defined as less than 0.4V), VCC (3.3V or 5V), VPP, or a high impedance state, are available. When either the high impedance or low voltage conditions are selected, the device switches into "sleep" mode and draws only nanoamperes of leakage current. The MIC2558 is a dual low-resistance power MOSFET switching matrix that operates from the computer system main power supply. Device power is obtained from VDD, which may be either 3.3V or 5V, and FET drive is obtained from VPP IN (usually +12V). Internal break-before-make switches determine the output voltage and device mode. VPP1 and VPP2 are completely indepenent from each other. Supply Bypassing For best results, bypass VCC and VPP IN inputs with 1µF capacitors. Both VPP OUT pins should have a 0.01µF to 0.1 µF capacitor for noise reduction and electrostatic dis- charge (ESD) damage prevention. Larger values of output capacitor will create large current spikes during transitions, requiring larger bypass capacitors on the VCC and VPP IN pins. Figure 3. MIC2558 Typical two slot PCMCIA applica- tion with single 5.0V V CC. System Power Supply PCMCIA Card Slot Controller MIC2558 PCMCIA Card Slot A PCMCIA Card Slot B MIC2558 5V 12V EN01 EN11 EN12 EN02 EN11 EN01 EN12 EN02 VPP1 VPP2 VCC VPP1 VPP2 VCC VCC Switch VPP IN VCC VPP IN VCC PCMCIA Implementation The Personal Computer Memory Card International Asso- ciation (PCMCIA) specification requires two VPP supply pins per PCMCIA slot. VPP is primarily used for programming Flash (EEPROM) memory cards. The two VPP supply pins may be programmed to different voltages. Fully implement- ing PCMCIA specifications requires a MIC2558 and a con- troller. Figure 2 shows this full configuration, supporting both 5.0V and 3.3V VCC operation. Figure 3 is a simplified design with fixed VCC = 5V. When a memory card is initially inserted, it should receive VCC — usually 5.0V ±5%. The card sends a handshaking data stream to the controller, which then determines whether or not this card requires VPP and if the card is designed for 5.0V or 3.3V VCC. If the card uses 3.3V VCC, the controller commands this change, which is reflected on the VCC pins of both the PCMCIA slot and the MIC2558. During Flash memory programming, the PCMCIA controller outputs a (1,0) to one or both halves of the MIC2558, which connects VPP IN to VPP OUT1 and/or VPP OUT2. The low ON resistance of the MIC2558 switch requires only a small bypass capacitor on the VPP OUT pins, with the main filtering System Power Supply PCMCIA Card Slot Controller VCC Select and Switch MIC2558 PCMCIA Card Slot A PCMCIA Card Slot B VCC Select and Switch MIC2558 5V 3.3V 12V EN01 EN11 EN12 EN02 EN11 EN01 EN12 EN02 VPP1 VPP2 VCC VPP1 VPP2 VCC VPP IN VCC VPP IN VCC Figure 2. MIC2558 Typical two slot PCMCIA applica- tion with dual V CC (5.0V or 3.3V). |
Similar Part No. - MIC2558 |
|
Similar Description - MIC2558 |
|
|
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 |