LM2501 National Semiconductor, LM2501 Datasheet - Page 12

• Manufacturer Part Number: LM2501
• Description: Mobile Pixel Link (MPL) Camera Interface Serializer and Deserializer
• Manufacturer: National Semiconductor

www.national.com
Features and Operation
POWER DOWN/OFF
The device may be powered by its PD* pin. A Low on this pin
will power down the entire device.
UN-USED/OPEN INPUTS
Un-used control/inputs pins must be driven to their appropri-
ate logic states to set up the desired operating modes.
UN-USED OUTPUTS
Unused outputs should be left open to minimize power dis-
sipation.
POWERING UP
The LM2501 should be powered up with all power supplies
at the same time, alternately VDDIO may lag VDD and
VDDA. Do not power up with VDDIO before VDD and VDDA.
Mode
SER
SER
SER
DES
DES
DES
DES
TABLE 2. Power Down Output States
WCLKIO
D[0:7]
PCLK
V, H
WC
Pin
MC
MD
LVCMOS
LVCMOS
LVCMOS
LVCMOS
Type
MPL
MPL
MPL
in Power Down
Output State
LOW
LOW
LOW
LOW
OFF
OFF
OFF
FIGURE 10. Sleep to Active
12
PHASE-LOCKED LOOP
When the device is configured as a Serializer, a PLL is
provided to generate the serial link clock. The Phase-locked
loop system generates the serial data clock at five times the
input clock. The PLL operates with an input clock between
4 MHz and 16 MHz. The Deserializer does not utilize the PLL
and its PLL is powered down.
RESET
PD* should be held Low until the power supply has powered
up and is stable. The PD* should then be de-asserted to
generate a RESET and start up. Stopping the WCLKIO or
the PCLK will not RESET the part. A power cycle or PD*
cycle is requested to generate a RESET event.
SERIALIZER/DESERIALIZER SELECTION
The Mode[1:0] pins are used to configure the device as
either a Serializer or Deserializer and other configuration
options.
WHISPERCLOCK
An additional clock signal is sent from the Deserializer to the
Serializer. This can be used to pass a clock reference
(4 MHz to 28 MHz) up to the Camera device from the host.
This link is independent of the Serial data path (opposite
direction). See also Figure 5. The SER can only start up, if
the WCLKIO(ser-out) has been active.
20091608