ETC 24LC21I/P

24LC21
1K 2.5V Dual Mode I2C™ Serial EEPROM
FEATURES
PACKAGE TYPES
PDIP
1
8
VCC
NC
2
7
VCLK
NC
3
6
SCL
VSS
4
5
SDA
NC
1
8
VCC
NC
2
7
VCLK
NC
3
5
SCL
VSS
4
5
SDA
SOIC
24LC21
DESCRIPTION
The Microchip Technology Inc. 24LC21 is a 128 x 8 bit
Electrically Erasable PROM. This device is designed
for use in applications requiring storage and serial
transmission of configuration and control information.
Two modes of operation have been implemented:
Transmit Only Mode and Bi-Directional Mode. Upon
power-up, the device will be in the Transmit Only Mode,
sending a serial bit stream of the entire memory array
contents, clocked by the VCLK pin. A valid high to low
transition on the SCL pin will cause the device to enter
the Bi-Directional Mode, with byte selectable read/write
capability of the memory array. The 24LC21 is available
in a standard 8-pin PDIP and SOIC package in both
commercial and industrial temperature ranges.
NC
24LC21
• Single supply with operation down to 2.5V
• Completely implements DDC1/DDC2 interface for monitor identification
• Low power CMOS technology
- 1 mA active current typical
- 10 µA standby current typical at 5.5V
• 2-wire serial interface bus, I2C compatible
• Self-timed write cycle (including auto-erase)
• Page-write buffer for up to 8 bytes
• 100 kHz (2.5V) and 400 kHz (5V) compatibility
• Factory programming (QTP) available
• 1,000,000 erase/write cycles ensured
• Data retention > 200 years
• 8-pin PDIP and SOIC package
• Available for extended temperature ranges
- Commercial (C):
0°C to +70°C
- Industrial (I):
-40°C to +85°C
BLOCK DIAGRAM
VCLK
HV GENERATOR
I/O
CONTROL
LOGIC
MEMORY
CONTROL
LOGIC
XDEC
EEPROM
ARRAY
PAGE LATCHES
SDA
SCL
YDEC
VCC
VSS
SENSE AMP
R/W CONTROL
DDC is a trademark of the Video Electronics Standards Association.
I2C is a trademark of Philips Corporation.
 2001 Microchip Technology Inc.
DS21095H-page 1
24LC21
1.0
ELECTRICAL CHARACTERISTICS
1.1
Maximum Ratings*
TABLE 1-1:
VCC...................................................................................7.0V
All inputs and outputs w.r.t. VSS ............... -0.6V to VCC +1.0V
Storage temperature .....................................-65°C to +150°C
Ambient temp. with power applied ................-65°C to +125°C
Soldering temperature of leads (10 seconds) ............. +300°C
ESD protection on all pins ..................................................≥ 4 kV
*Notice: Stresses above those listed under “Maximum ratings”
may cause permanent damage to the device. This is a stress rating only and functional operation of the device at those or any
other conditions above those indicated in the operational listings
of this specification is not implied. Exposure to maximum rating
conditions for extended periods may affect device reliability.
TABLE 1-2:
PIN FUNCTION TABLE
Name
Function
VSS
SDA
SCL
VCLK
VCC
NC
Ground
Serial Address/Data I/O
Serial Clock (Bi-Directional Mode)
Serial Clock (Transmit-Only Mode)
+2.5V to 5.5V Power Supply
No Connection
DC CHARACTERISTICS
VCC = +2.5V to 5.5V
Commercial (C): TAMB = 0°C to +70°C
Industrial
(I):
TAMB = -40°C to +85°C
Parameter
SCL and SDA pins:
High level input voltage
Low level input voltage
Input levels on VCLK pin:
High level input voltage
Low level input voltage
Hysteresis of Schmitt trigger inputs
Low level output voltage
Low level output voltage
Input leakage current
Output leakage current
Pin capacitance (all inputs/outputs)
Operating current
Standby current
Symbol
Min
Max
Units
Conditions
VIH
VIL
.7 VCC
—
—
.3 VCC
V
V
—
—
VIH
VIL
VHYS
VOL1
VOL2
ILI
ILO
CIN, COUT
2.0
—
.05 VCC
—
—
-10
-10
—
.8
.2 VCC
—
.4
.6
10
10
10
V
V
V
V
V
µA
µA
pF
ICC Write
ICC Read
ICCS
—
—
—
—
3
1
30
100
mA
mA
µA
µA
VCC ≥ 2.7V (Note 1)
VCC < 2.7V (Note 1)
(Note 1)
IOL = 3 mA, VCC = 2.5V (Note 1)
IOL = 6 mA, VCC = 2.5V
VIN = .1V to VCC
VOUT = .1V to VCC
VCC = 5.0V (Note1),
TAMB = 25°C, FCLK = 1 MHz
VCC = 5.5V, SCL = 400 kHz
VCC = 3.0V, SDA = SCL = VCC
VCC = 5.5V, SDA = SCL = VCC
(Note 2)
Note 1: This parameter is periodically sampled and not 100% tested.
2: VLCK must be grounded.
DS21095H-page 2
 2001 Microchip Technology Inc.
24LC21
TABLE 1-3:
AC CHARACTERISTICS
Standard Mode
Parameter
Symbol
Vcc= 4.5 - 5.5V
Fast Mode
Units
Remarks
400
—
—
300
300
—
kHz
ns
ns
ns
ns
ns
600
—
ns
—
—
—
3500
—
0
100
600
—
1300
—
—
—
900
—
ns
ns
ns
ns
ns
—
250
250
ns
—
50
20 + .1
CB
—
—
—
—
(Note 1)
(Note 1)
After this period the first clock
pulse is generated
Only relevant for repeated
START condition
(Note 2)
—
—
(Note 2)
Time the bus must be free
before a new transmission
can start
(Note 1), CB ≤ 100 pF
50
ns
(Note 3)
—
10
—
10
ms
Byte or Page mode
—
4000
4700
—
0
2000
—
—
500
—
—
600
1300
—
0
1000
—
—
500
—
ns
ns
ns
ns
ns
—
—
—
—
—
1M
—
1M
—
cycles
Min
Max
Min
Max
Clock frequency
FCLK
Clock high time
THIGH
Clock low time
TLOW
SDA and SCL rise time
TR
SDA and SCL fall time
TF
START condition hold time THD:STA
—
4000
4700
—
—
4000
100
—
—
1000
300
—
—
600
1300
—
—
600
TSU:STA
4700
—
THD:DAT
TSU:DAT
TSU:STO
TAA
TBUF
0
250
4000
—
4700
START condition setup
time
Data input hold time
Data input setup time
STOP condition setup time
Output valid from clock
Bus free time
TOF
Output fall time from VIH
min to VIL max
Input filter spike suppresTSP
sion (SDA and SCL pins)
Write cycle time
TWR
Transmit-Only Mode Parameters
Output valid from VCLK
TVAA
VCLK high time
TVHIGH
VCLK low time
TVLOW
Mode transition time
TVHZ
Transmit-Only power up
TVPU
time
Endurance
—
25°C, VCC = 5.0V, Block
Mode (Note 4)
Note 1: Not 100% tested. CB = total capacitance of one bus line in pF.
2: As a transmitter, the device must provide an internal minimum delay time to bridge the undefined region
(minimum 300 ns) of the falling edge of SCL to avoid unintended generation of START or STOP conditions.
3: The combined TSP and VHYS specifications are due to new Schmitt trigger inputs which provide improved
noise and spike suppression. This eliminates the need for a TI specification for standard operation.
4: This parameter is not tested but ensured by characterization. For endurance estimates in a specific application, please consult the Total Endurance Model which can be obtained on our website: www.microchip.com
 2001 Microchip Technology Inc.
DS21095H-page 3
24LC21
2.0
FUNCTIONAL DESCRIPTION
The 24LC21 operates in two modes, the Transmit-Only
Mode and the Bi-Directional Mode. There is a separate
two wire protocol to support each mode, each having a
separate clock input and sharing a common data line
(SDA). The device enters the Transmit-Only Mode
upon power-up. In this mode, the device transmits data
bits on the SDA pin in response to a clock signal on the
VCLK pin. The device will remain in this mode until a
valid high to low transition is placed on the SCL input.
When a valid transition on SCL is recognized, the
device will switch into the Bi-Directional Mode. The only
way to switch the device back to the Transmit-Only
Mode is to remove power from the device.
2.1
Transmit-Only Mode
The device will power up in the Transmit-Only Mode.
This mode supports a unidirectional two wire protocol
for transmission of the contents of the memory array.
This device requires that it be initialized prior to valid
data being sent in the Transmit-Only Mode (see Initialization Procedure, below). In this mode, data is transmitted on the SDA pin in 8 bit bytes, each followed by a
FIGURE 2-1:
ninth, null bit (see Figure 2-1). The clock source for the
Transmit-Only Mode is provided on the VCLK pin, and a
data bit is output on the rising edge on this pin. The
eight bits in each byte are transmitted most significant
bit first. Each byte within the memory array will be output in sequence. When the last byte in the memory
array is transmitted, the output will wrap around to the
first location and continue. The Bi-Directional Mode
Clock (SCL) pin must be held high for the device to
remain in the Transmit-Only Mode.
2.2
Initialization Procedure
After VCC has stabilized, the device will be in the Transmit-Only Mode. Nine clock cycles on the VCLK pin must
be given to the device for it to perform internal synchronization. During this period, the SDA pin will be in a
high impedance state. On the rising edge of the tenth
clock cycle, the device will output the first valid data bit
which will be the most significant bit of a byte. The
device will power up at an indeterminate byte address.
(Figure 2-2).
TRANSMIT ONLY MODE
SCL
TVAA
TVAA
SDA
NULL BIT
BIT 1 (LSB)
BIT 1 (MSB)
BIT 7
VCLK
TVHIGH
FIGURE 2-2:
TVLOW
DEVICE INITIALIZATION
VCC
SCL
SDA
TVAA
HIGH IMPEDANCE FOR 9 CLOCK CYCLES
TVAA
BIT 8
BIT 7
TVPU
VCLK
DS21095H-page 4
1
2
8
9
10
11
 2001 Microchip Technology Inc.
24LC21
3.0
BI-DIRECTIONAL MODE
3.1
The 24LC21 can be switched into the Bi-Directional
Mode (see Figure 3-1) by applying a valid high to low
transition on the Bi-Directional Mode Clock (SCL).
When the device has been switched into the Bi-Directional Mode, the VCLK input is disregarded, with the
exception that a logic high level is required to enable
write capability. This mode supports a two wire bi-directional data transmission protocol. In this protocol, a
device that sends data on the bus is defined to be the
transmitter, and a device that receives data from the
bus is defined to be the receiver. The bus must be controlled by a master device that generates the Bi-Directional Mode Clock (SCL), controls access to the bus
and generates the START and STOP conditions, while
the 24LC21 acts as the slave. Both master and slave
can operate as transmitter or receiver, but the master
device determines which mode is activated.
Bi-Directional Mode Bus
Characteristics
The following bus protocol has been defined:
• Data transfer may be initiated only when the bus
is not busy.
• During data transfer, the data line must remain
stable whenever the clock line is HIGH. Changes
in the data line while the clock line is HIGH will be
interpreted as a START or STOP condition.
Accordingly, the following bus conditions have been
defined (see Figure 3-2).
3.1.1
BUS NOT BUSY (A)
Both data and clock lines remain HIGH.
3.1.2
START DATA TRANSFER (B)
A HIGH to LOW transition of the SDA line while the
clock (SCL) is HIGH determines a START condition. All
commands must be preceded by a START condition.
3.1.3
STOP DATA TRANSFER (C)
A LOW to HIGH transition of the SDA line while the
clock (SCL) is HIGH determines a STOP condition. All
operations must be ended with a STOP condition.
FIGURE 3-1:
MODE TRANSITION
Transmit Only Mode
Bi-Directional Mode
SCL
TVHZ
SDA
VCLK
FIGURE 3-2:
(A)
DATA TRANSFER SEQUENCE ON THE SERIAL BUS
(B)
(D)
START
CONDITION
ADDRESS OR
ACKNOWLEDGE
VALID
(D)
(C)
(A)
SCL
SDA
 2001 Microchip Technology Inc.
DATA
ALLOWED
TO CHANGE
STOP
CONDITION
DS21095H-page 5
24LC21
3.1.4
DATA VALID (D)
3.1.5
The state of the data line represents valid data when,
after a START condition, the data line is stable for the
duration of the HIGH period of the clock signal.
Each receiving device, when addressed, is obliged to
generate an acknowledge after the reception of each
byte. The master device must generate an extra clock
pulse which is associated with this acknowledge bit.
The data on the line must be changed during the LOW
period of the clock signal. There is one clock pulse per
bit of data.
Note:
Each data transfer is initiated with a START condition
and terminated with a STOP condition. The number of
the data bytes transferred between the START and
STOP conditions is determined by the master device
and is theoretically unlimited, although only the last
eight will be stored when doing a write operation.
When an overwrite does occur it will replace data in a
first in first out fashion.
FIGURE 3-3:
ACKNOWLEDGE
The 24LC21 does not generate any
acknowledge bits if an internal programming cycle is in progress.
The device that acknowledges has to pull down the
SDA line during the acknowledge clock pulse in such a
way that the SDA line is stable LOW during the HIGH
period of the acknowledge related clock pulse. Of
course, setup and hold times must be taken into
account. A master must signal an end of data to the
slave by not generating an acknowledge bit on the last
byte that has been clocked out of the slave. In this
case, the slave must leave the data line HIGH to enable
the master to generate the STOP condition.
BUS TIMING START/STOP
VHYS
SCL
THD:STA
TSU:STA
TSU:STO
SDA
START
FIGURE 3-4:
STOP
BUS TIMING DATA
TR
TF
THIGH
TLOW
SCL
TSU:STA
THD:DAT
TSU:DAT
TSU:STO
THD:STA
SDA
IN
TSP
TAA
THD:STA
TAA
TBUF
SDA
OUT
DS21095H-page 6
 2001 Microchip Technology Inc.
24LC21
3.1.6
4.2
SLAVE ADDRESS
After generating a START condition, the bus master
transmits the slave address consisting of a 7-bit device
code (1010) for the 24LC21, followed by three don’t
care bits.
The eighth bit of slave address determines if the master
device wants to read or write to the 24LC21
(Figure 3-5).
The 24LC21 monitors the bus for its corresponding
slave address all the time. It generates an acknowledge bit if the slave address was true and it is not in a
programming mode.
Operation
Control Code
Chip Select
R/W
Read
Write
1010
1010
XXX
XXX
1
0
FIGURE 3-5:
The write control byte, word address and the first data
byte are transmitted to the 24LC21 in the same way as
in a byte write. But instead of generating a stop condition the master transmits up to eight data bytes to the
24LC21 which are temporarily stored in the on-chip
page buffer and will be written into the memory after the
master has transmitted a stop condition. After the
receipt of each word, the three lower order address
pointer bits are internally incremented by one. The
higher order five bits of the word address remains constant. If the master should transmit more than eight
words prior to generating the stop condition, the
address counter will roll over and the previously
received data will be overwritten. As with the byte write
operation, once the stop condition is received an internal write cycle will begin (Figure 4-3).
It is required that VCLK be held at a logic high level in
order to program the device. This applies to byte write
and page write operation. Note that VCLK can go low
while the device is in its self-timed program operation
and not affect programming.
CONTROL BYTE
ALLOCATION
START
READ/WRITE
Note:
SLAVE ADDRESS
1
0
1
0
X
R/W
X
4.0
WRITE OPERATION
4.1
Byte Write
Page Write
A
X
Following the start signal from the master, the slave
address (4 bits), the don’t care bits (3 bits) and the R/W
bit which is a logic low is placed onto the bus by the
master transmitter. This indicates to the addressed
slave receiver that a byte with a word address will follow after it has generated an acknowledge bit during
the ninth clock cycle. Therefore, the next byte transmitted by the master is the word address and will be written into the address pointer of the 24LC21. After
receiving another acknowledge signal from the 24LC21
the master device will transmit the data word to be written into the addressed memory location. The 24LC21
acknowledges again and the master generates a stop
condition. This initiates the internal write cycle, and during this time the 24LC21 will not generate acknowledge
signals (Figure 4-1).
Page write operations are limited to
writing bytes within a single physical
page, regardless of the number of
bytes actually being written. Physical
page boundaries start at addresses that
are integer multiples of the page buffer
size (or ‘page size’) and end at
addresses that are integer multiples of
[page size - 1]. If a page write command
attempts to write across a physical
page boundary, the result is that the
data wraps around to the beginning of
the current page (overwriting data previously stored there), instead of being
written to the next page as might be
expected. It is therefore necessary for
the application software to prevent
page write operations that would
attempt to cross a page boundary.
It is required that VCLK be held at a logic high level in
order to program the device. This applies to byte write
and page write operation. Note that VCLK can go low
while the device is in its self-timed program operation
and not affect programming.
DS21095H-page 7
 2001 Microchip Technology Inc.
24LC21
FIGURE 4-1:
BYTE WRITE
BUS ACTIVITY
MASTER
S
T
A
R
T
SDA LINE
S
CONTROL
BYTE
WORD
ADDRESS
S
T
O
P
DATA
P
A
C
K
BUS ACTIVITY
A
C
K
A
C
K
VCLK
FIGURE 4-2:
BYTE WRITE
BUS ACTIVITY
MASTER
S
T
A
R
T
SDA LINE
S
CONTROL
BYTE
WORD
ADDRESS
S
T
O
P
DATA
P
A
C
K
BUS ACTIVITY
A
C
K
A
C
K
VCLK
FIGURE 4-3:
PAGE WRITE
BUS ACTIVITY
MASTER
S
T
A
R
T
SDA LINE
S
BUS ACTIVITY
WORD
ADDRESS
CONTROL
BYTE
DATA (n + 1)
DATA (n)
S
T
O
P
DATA (n + 15)
P
A
C
K
A
C
K
A
C
K
A
C
K
A
C
K
VCLK
DS21095H-page 8
 2001 Microchip Technology Inc.
24LC21
5.0
ACKNOWLEDGE POLLING
Since the device will not acknowledge during a write
cycle, this can be used to determine when the cycle is
complete (this feature can be used to maximize bus
throughput). Once the stop condition for a write command has been issued from the master, the device initiates the internally timed write cycle. ACK polling can
be initiated immediately. This involves the master sending a start condition followed by the control byte for a
write command (R/W = 0). If the device is still busy with
the write cycle, then no ACK will be returned. If the
cycle is complete, then the device will return the ACK
and the master can then proceed with the next read or
write command. See Figure 5-1 for the flow diagram.
FIGURE 5-1:
ACKNOWLEDGE POLLING
FLOW
Send
Write Command
7.0
Read operations are initiated in the same way as write
operations with the exception that the R/W bit of the
slave address is set to ‘1’. There are three basic types
of read operations: current address read, random read
and sequential read.
7.1
Random Read
Random read operations allow the master to access
any memory location in a random manner. To perform
this type of read operation, first the word address must
be set. This is done by sending the word address to the
24LC21 as part of a write operation. After the word
address is sent, the master generates a start condition
following the acknowledge. This terminates the write
operation, but not before the internal address pointer is
set. Then the master issues the control byte again but
with the R/W bit set to a ‘1’. The 24LC21 will then issue
an acknowledge and transmits the eight bit data word.
The master will not acknowledge the transfer but does
generate a stop condition and the 24LC21 discontinues
transmission (Figure 7-2).
Send Stop
Condition to
Initiate Write Cycle
Send Start
Send Control Byte
with R/W = 0
No
Yes
Next
Operation
6.0
Current Address Read
The 24LC21 contains an address counter that maintains the address of the last word accessed, internally
incremented by one. Therefore, if the previous access
(either a read or write operation) was to address n, the
next current address read operation would access data
from address n + 1. Upon receipt of the slave address
with R/W bit set to ‘1’, the 24LC21 issues an acknowledge and transmits the eight bit data word. The master
will not acknowledge the transfer but does generate a
stop condition and the 24LC21 discontinues transmission (Figure 7-1).
7.2
Did Device
Acknowledge
(ACK = 0)?
READ OPERATION
WRITE PROTECTION
When using the 24LC21 in the Bi-Directional Mode, the
VCLK pin operates as the write protect control pin. Setting VCLK high allows normal write operations, while
setting VCLK low prevents writing to any location in the
array. Connecting the VCLK pin to VSS would allow the
24LC21 to operate as a serial ROM, although this configuration would prevent using the device in the Transmit-Only Mode.
7.3
Sequential Read
Sequential reads are initiated in the same way as a random read except that after the 24LC21 transmits the
first data byte, the master issues an acknowledge as
opposed to a stop condition in a random read. This
directs the 24LC21 to transmit the next sequentially
addressed 8-bit word (see Figure 7-3).
To provide sequential reads the 24LC21 contains an
internal address pointer which is incremented by one at
the completion of each operation. This address pointer
allows the entire memory contents to be serially read
during one operation.
7.4
Noise Protection
The 24LC21 employs a VCC threshold detector circuit
which disables the internal erase/write logic if the VCC
is below 1.5 volts at nominal conditions.
The SCL and SDA inputs have Schmitt trigger and filter
circuits which suppress noise spikes to assure proper
device operation even on a noisy bus.
DS21095H-page 9
 2001 Microchip Technology Inc.
24LC21
FIGURE 7-1:
CURRENT ADDRESS READ
BUS ACTIVITY
MASTER
S
T
A
R
T
SDA LINE
S
CONTROL
BYTE
P
N
O
A
C
K
BUS ACTIVITY
FIGURE 7-2:
S
T
O
P
DATA (n)
A
C
K
RANDOM READ
S
T
T
S
T
A
R
T
S
S
CONTROL
BYTE
BUS ACTIVITY A
MASTER
R
SDA LINE
WORD
ADDRESS
A
C
K
BUS ACTIVITY
CONTROL
BYTE
S
T
O
P
DATA (n)
P
A
C
K
A
C
K
N
O
A
C
K
FIGURE 7-3:
BUS ACTIVITY
MASTER
SEQUENTIAL READ
CONTROL
BYTE
DATA (n)
DATA (n + 1)
DATA (n + 2)
S
T
O
P
DATA (n + X)
P
SDA LINE
BUS ACTIVITY
A
C
K
A
C
K
A
C
K
A
C
K
N
O
A
C
K
8.0
PIN DESCRIPTIONS
8.2
8.1
SDA
This pin is the clock input for the Bi-Directional Mode,
and is used to synchronize data transfer to and from the
device. It is also used as the signaling input to switch
the device from the Transmit Only Mode to the Bi-Directional Mode. It must remain high for the chip to continue
operation in the Transmit Only Mode.
This pin is used to transfer addresses and data into and
out of the device, when the device is in the Bi-Directional Mode. In the Transmit-Only Mode, which only
allows data to be read from the device, data is also
transferred on the SDA pin. This pin is an open drain
terminal, therefore the SDA bus requires a pullup resistor to VCC (typical 10KΩ for 100 kHz, 2KΩ for 400 kHz).
For normal data transfer in the Bi-Directional Mode,
SDA is allowed to change only during SCL low.
Changes during SCL high are reserved for indicating
the START and STOP conditions.
 2001 Microchip Technology Inc.
8.3
SCL
VCLK
This pin is the clock input for the Transmit Only Mode.
In the Transmit Only Mode, each bit is clocked out on
the rising edge of this signal. In the Bi-Directional
Mode, a high logic level is required on this pin to enable
write capability.
DS21095H-page 10
24LC21
24LC21 Product Identification System
To order or to obtain information, e.g., on pricing or delivery, please use the listed part numbers, and refer to the factory or the listed
sales offices.
24LC21
-
/P
Package:
Temperature
Range:
Device:
P = Plastic DIP (300 mil Body), 8-lead
SN = Plastic SOIC (150 mil Body), 8-lead
Blank = 0°C to +70°C
I = -40°C to +85°C
24LC21
24LC21T
Dual Mode I2C Serial EEPROM
Dual Mode I2C Serial EEPROM (Tape and Reel)
Sales and Support
Data Sheets
Products supported by a preliminary Data Sheet may have an errata sheet describing minor operational differences and recommended workarounds. To determine if an errata sheet exists for a particular device, please contact one of the following:
1. Your local Microchip sales office
2. The Microchip Corporate Literature Center U.S. FAX: (480) 792-7277
3. The Microchip Worldwide Web Site (www.microchip.com)
Please specify which device, revision of silicon and Data Sheet (include Literature #) you are using.
New Customer Notification System
Register on our web site (www.microchip.com/cn) to receive the most current information on our products.
 2001 Microchip Technology Inc.
DS21095H-page 11
24LC21
NOTES:
 2001 Microchip Technology Inc.
DS21095H-page 12
24LC21
NOTES:
DS21095H-page 13
 2001 Microchip Technology Inc.
24LC21
NOTES:
 2001 Microchip Technology Inc.
DS21095H-page 14
24LC21
“All rights reserved. Copyright © 2001, Microchip
Technology Incorporated, USA. Information contained
in this publication regarding device applications and the
like is intended through suggestion only and may be
superseded by updates. No representation or warranty
is given and no liability is assumed by Microchip
Technology Incorporated with respect to the accuracy
or use of such information, or infringement of patents or
other intellectual property rights arising from such use
or otherwise. Use of Microchip’s products as critical
components in life support systems is not authorized
except with express written approval by Microchip. No
licenses are conveyed, implicitly or otherwise, under
any intellectual property rights. The Microchip logo and
name are registered trademarks of Microchip
Technology Inc. in the U.S.A. and other countries. All
rights reserved. All other trademarks mentioned herein
are the property of their respective companies. No
licenses are conveyed, implicitly or otherwise, under
any intellectual property rights.”
Trademarks
The Microchip name, logo, PIC, PICmicro,
PICMASTER, PICSTART, PRO MATE, KEELOQ,
SEEVAL, MPLAB and The Embedded Control
Solutions Company are registered trademarks of
Microchip Technology Incorporated in the U.S.A. and
other countries.
Total Endurance, ICSP, In-Circuit Serial Programming,
FilterLab, MXDEV, microID, FlexROM, fuzzyLAB,
MPASM, MPLINK, MPLIB, PICDEM, ICEPIC,
Migratable Memory, FanSense, ECONOMONITOR,
SelectMode and microPort are trademarks of
Microchip Technology Incorporated in the U.S.A.
Serialized Quick Term Programming (SQTP) is a
service mark of Microchip Technology Incorporated in
the U.S.A.
All other trademarks mentioned herein are property of
their respective companies.
© 2001, Microchip Technology Incorporated, Printed in
the U.S.A., All Rights Reserved.
Microchip received QS-9000 quality system
certification for its worldwide headquarters,
design and wafer fabrication facilities in
Chandler and Tempe, Arizona in July 1999. The
Company’s quality system processes and
procedures are QS-9000 compliant for its
PICmicro® 8-bit MCUs, KEELOQ® code hopping
devices, Serial EEPROMs and microperipheral
products. In addition, Microchip’s quality
system for the design and manufacture of
development systems is ISO 9001 certified.
DS21095H-page 15
 2001 Microchip Technology Inc.
WORLDWIDE SALES AND SERVICE
AMERICAS
New York
Corporate Office
150 Motor Parkway, Suite 202
Hauppauge, NY 11788
Tel: 631-273-5305 Fax: 631-273-5335
2355 West Chandler Blvd.
Chandler, AZ 85224-6199
Tel: 480-792-7200 Fax: 480-792-7277
Technical Support: 480-792-7627
Web Address: http://www.microchip.com
Rocky Mountain
2355 West Chandler Blvd.
Chandler, AZ 85224-6199
Tel: 480-792-7966 Fax: 480-792-7456
Atlanta
500 Sugar Mill Road, Suite 200B
Atlanta, GA 30350
Tel: 770-640-0034 Fax: 770-640-0307
Austin
Analog Product Sales
8303 MoPac Expressway North
Suite A-201
Austin, TX 78759
Tel: 512-345-2030 Fax: 512-345-6085
Boston
2 Lan Drive, Suite 120
Westford, MA 01886
Tel: 978-692-3848 Fax: 978-692-3821
Boston
Analog Product Sales
Unit A-8-1 Millbrook Tarry Condominium
97 Lowell Road
Concord, MA 01742
Tel: 978-371-6400 Fax: 978-371-0050
Chicago
333 Pierce Road, Suite 180
Itasca, IL 60143
Tel: 630-285-0071 Fax: 630-285-0075
Dallas
4570 Westgrove Drive, Suite 160
Addison, TX 75001
Tel: 972-818-7423 Fax: 972-818-2924
Dayton
Two Prestige Place, Suite 130
Miamisburg, OH 45342
Tel: 937-291-1654 Fax: 937-291-9175
Detroit
Tri-Atria Office Building
32255 Northwestern Highway, Suite 190
Farmington Hills, MI 48334
Tel: 248-538-2250 Fax: 248-538-2260
Los Angeles
18201 Von Karman, Suite 1090
Irvine, CA 92612
Tel: 949-263-1888 Fax: 949-263-1338
Mountain View
Analog Product Sales
1300 Terra Bella Avenue
Mountain View, CA 94043-1836
Tel: 650-968-9241 Fax: 650-967-1590
ASIA/PACIFIC (continued)
Korea
Microchip Technology Korea
168-1, Youngbo Bldg. 3 Floor
Samsung-Dong, Kangnam-Ku
Seoul, Korea
Tel: 82-2-554-7200 Fax: 82-2-558-5934
San Jose
Microchip Technology Inc.
2107 North First Street, Suite 590
San Jose, CA 95131
Tel: 408-436-7950 Fax: 408-436-7955
Singapore
Microchip Technology Singapore Pte Ltd.
200 Middle Road
#07-02 Prime Centre
Singapore, 188980
Tel: 65-334-8870 Fax: 65-334-8850
Toronto
6285 Northam Drive, Suite 108
Mississauga, Ontario L4V 1X5, Canada
Tel: 905-673-0699 Fax: 905-673-6509
Taiwan
Microchip Technology Taiwan
11F-3, No. 207
Tung Hua North Road
Taipei, 105, Taiwan
Tel: 886-2-2717-7175 Fax: 886-2-2545-0139
ASIA/PACIFIC
Australia
Microchip Technology Australia Pty Ltd
Suite 22, 41 Rawson Street
Epping 2121, NSW
Australia
Tel: 61-2-9868-6733 Fax: 61-2-9868-6755
EUROPE
China - Beijing
Denmark
Microchip Technology Beijing Office
Unit 915
New China Hong Kong Manhattan Bldg.
No. 6 Chaoyangmen Beidajie
Beijing, 100027, No. China
Tel: 86-10-85282100 Fax: 86-10-85282104
Microchip Technology Denmark ApS
Regus Business Centre
Lautrup hoj 1-3
Ballerup DK-2750 Denmark
Tel: 45 4420 9895 Fax: 45 4420 9910
France
China - Shanghai
Microchip Technology Shanghai Office
Room 701, Bldg. B
Far East International Plaza
No. 317 Xian Xia Road
Shanghai, 200051
Tel: 86-21-6275-5700 Fax: 86-21-6275-5060
Hong Kong
Microchip Asia Pacific
RM 2101, Tower 2, Metroplaza
223 Hing Fong Road
Kwai Fong, N.T., Hong Kong
Tel: 852-2401-1200 Fax: 852-2401-3431
India
Microchip Technology Inc.
India Liaison Office
Divyasree Chambers
1 Floor, Wing A (A3/A4)
No. 11, O’Shaugnessey Road
Bangalore, 560 025, India
Tel: 91-80-2290061 Fax: 91-80-2290062
Japan
Microchip Technology Intl. Inc.
Benex S-1 6F
3-18-20, Shinyokohama
Kohoku-Ku, Yokohama-shi
Kanagawa, 222-0033, Japan
Tel: 81-45-471- 6166 Fax: 81-45-471-6122
Arizona Microchip Technology SARL
Parc d’Activite du Moulin de Massy
43 Rue du Saule Trapu
Batiment A - ler Etage
91300 Massy, France
Tel: 33-1-69-53-63-20 Fax: 33-1-69-30-90-79
Germany
Arizona Microchip Technology GmbH
Gustav-Heinemann Ring 125
D-81739 Munich, Germany
Tel: 49-89-627-144 0 Fax: 49-89-627-144-44
Germany
Analog Product Sales
Lochhamer Strasse 13
D-82152 Martinsried, Germany
Tel: 49-89-895650-0 Fax: 49-89-895650-22
Italy
Arizona Microchip Technology SRL
Centro Direzionale Colleoni
Palazzo Taurus 1 V. Le Colleoni 1
20041 Agrate Brianza
Milan, Italy
Tel: 39-039-65791-1 Fax: 39-039-6899883
United Kingdom
Arizona Microchip Technology Ltd.
505 Eskdale Road
Winnersh Triangle
Wokingham
Berkshire, England RG41 5TU
Tel: 44 118 921 5869 Fax: 44-118 921-5820
01/30/01
All rights reserved. © 2001 Microchip Technology Incorporated. Printed in the USA. 3/01
Printed on recycled paper.
Information contained in this publication regarding device applications and the like is intended through suggestion only and may be superseded by
updates. It is your responsibility to ensure that your application meets with your specifications. No representation or warranty is given and no liability is
assumed by Microchip Technology Incorporated with respect to the accuracy or use of such information, or infringement of patents or other intellectual
property rights arising from such use or otherwise. Use of Microchip’s products as critical components in life support systems is not authorized except with
express written approval by Microchip. No licenses are conveyed, implicitly or otherwise, except as maybe explicitly expressed herein, under any intellectual property rights. The Microchip logo and name are registered trademarks of Microchip Technology Inc. in the U.S.A. and other countries. All rights
reserved. All other trademarks mentioned herein are the property of their respective companies.
DS21095H-page 16
 2001 Microchip Technology Inc.