MIC2568-1YSM Micrel Inc, MIC2568-1YSM Datasheet - Page 8

• Manufacturer Part Number: MIC2568-1YSM
• Description: IC PCMCIA/CARDBUS DUAL 28-SSOP
• Manufacturer: Micrel Inc
• Type: PCMCIA/Cardbus Switchr

Specifications of MIC2568-1YSM

• Number Of Outputs: 4
• Rds (on): 4 Ohm
• Internal Switch(s): Yes
• Current Limit: 300mA
• Voltage - Input: 3.3V, 5V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 28-SSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

MIC2568
Applications Information
PC Card power control for two sockets is easily accomplished
using the Micrel MIC2568 PC Card/CardBus Slot Power
Controller IC.
Output Voltage Selection
Four control bits per socket determine V
voltages and standby- or operate-mode conditions. Input
logic threshold voltages are compatible with common PC
Card logic controllers using either 3.3V or 5V supplies.
The V
(ground) or 3.3V and 5V at the maximum allowable PC Card
current. The V
tween 0V (ground), 3.3V or 5V (V
high impedance. When V
MIC2568 goes into sleep mode and draws only nanoamperes
of leakage current.
Switching speeds are controlled to prevent damage to sensi-
tive loads and meet all PC Card Specification timing require-
ments. V
manded to switch directly from one V
first turning off and waiting 100ms), enhancement of the
second switch begins only after the first is off (break-before-
make protection).
Supply Input
The MIC2568 itself is powered from the V
nominal supply input). Bias its internal MOSFETs is gener-
ated by a charge pump quadrupler. Refer to “5V-Only V
Application” and Figure 4 for information on using the MIC2568
without a 3.3V supply.
Output Current and Protection
The MIC2568 meets or exceeds all PCMCIA current specifi-
cations. Its switches are capable of passing the maximum
current needed by any PC Card. For system and card
MIC2568
CC
CC
outputs can be individually switched between 0V
switches are turned on and off slowly. If com-
PP
outputs can be individually switched be-
between logic controller and
PCMCIA cards not shown.
Address and data lines
Logic Controller
CC
Dual-Slot
PC Card
= 0V (ground) is selected, the
CC3
CC
or V
to the other (without
CC
CC3
Figure 3. Basic V
CC5
and V
IN pin (3.3V-
voltages), or
A EN1
A EN0
A V
A V
B EN1
B EN0
B V
B V
PP
CC5
CC3
CC5
CC3
System Power Supply
A
output
EN
EN
EN
EN
⁄
B
V
3.3V
CC3
CC
IN
MIC2568-0
Controller
GND
Power
8
A
PP
(
⁄
OPTIONAL
B
V
protection, output currents are internally limited. For full
system protection, long-term output short circuits (millisec-
ond or longer) invoke overtemperature shutdown, protecting
the MIC2568, system power supplies, card socket pins, and
PC Card.
Bypass Capacitors
Both V
low-ESR surface-mount ceramic capacitors mounted near
the MIC2568 chip.
Both V
capacitors for noise reduction and to reduce the chance of
(electrostatic discharge) ESD damage.
PC Card Slot Implementation
The MIC2568 is designed for PC Card applications, including
the CardBus option, that do not require a 12V supply.
When a memory card is initially inserted, it must receive a V
voltage (either 3.3V 0.3V or 5.0V 5%). The initial voltage is
determined by a combination of mechanical socket keys and
voltage-sense pins. Each card sends handshaking data to
the logic controller which determines whether that card
requires a V
dual V
quests, a different V
waits at least 100ms, and then enables the new V
If no card is inserted, or the system is in sleep mode, the logic
controller outputs a (V
MIC2568, which shuts down V
into its high-impedance output sleep mode.
Basic V
Refer to Figure 3. A single system power supply feeds both
slot-A and slot-B supply inputs. Although the PC Card speci-
fication defines two V
they are usually connected together.
5V
CC5
and V
A V
B V
A V
B V
IN
CC
CC
PP
PP
)
OUT
OUT
OUT
OUT
CC3
CC
CC
CC
PP
OUT and V
Switch
voltages. If the card is compatible with, and re-
IN and V
and V
Motherboard
PP
Slot A
Slot B
voltage and whether the card is designed for
V
V
V
V
V
V
V
V
PP
PP
PP
PP
CC
CC
CC
CC
CC
1
2
1
2
CC5
Switch Application
PP
CC
PP
IN pins should be bypassed with 1 F
CC3
OUT pins may use 0.01 F to 0.1 F
outputs (V
level, the controller disables V
EN, V
CC
PC Card
PC Card
. This also places the switch
A
B
CC5
PP
1 and V
EN) = (0, 0) to the
PP
2) per card,
CC
May 2003
voltage.
Micrel
CC
CC
,