Philips Semiconductors
LPC2212/LPC2214
16/32-bit ARM microcontrollers with external memory interface
Table 13: External memory interface AC characteristics. CL = 25 pF. Tamb = 40 °C…continued
Symbol
Description
Min
Max
tAVDV
Burst-ROM Initial Memory Access Time
(latest of Address Valid, CS LOW, OE
LOW to Data Valid)
(tCYC*(2 + WST1)) + (−20) -
tAVDV
Burst-ROM Subsequent Memory Access tCYC + (−20)
-
Time (Address Valid to Data Valid)
tSTHDNV
Data Hold Time (earliest of CS HIGH, OE 0
-
HIGH, Address Change to Data Invalid)
tCSHOEH
CS HIGH to OE HIGH
−5
5
tOEHANV
OE HIGH to Address Invalid
−5
5
tCHOEL
XCLK HIGH to OE LOW
−5
5
tCHOEH
XCLK HIGH to OE HIGH
−5
5
Write Cycle Parameters
tAVCSLW
tCSLDVW
tCSLWEL
tCSLBLSL
tWELDV
tCSLDV
tWELWEH
tWELWEH
tWEHANV
tWEHDNV
tBLSHANV
tBLSHDNV
Address Valid to CS LOW
CS LOW to Data Valid
CS LOW to WE LOW
CS LOW to BLS LOW
WE LOW to Data Valid
CS LOW to Data Valid
WE LOW to WE HIGH
BLS LOW to BLS HIGH
WE HIGH to Address Invalid
WE HIGH to Data Invalid
BLS HIGH to Address Invalid
BLS HIGH to Data Invalid
tCYC − 10 [1]
−5
−5
−5
−5
−5
tCYC × (1 + WST2) − 5
tCYC × (1 + WST2) − 5
tCYC−5
(2 × tCYC)−5
tCYC−5
(2 × tCYC)−5
-
5
5
5
5
5
tCYC*(1 + WST2) + 5
tCYC*(1 + WST2) + 5
tCYC + 5
(2 × tCYC) + 5
tCYC + 5
(2 × tCYC) + 5
tCHDV
XCLK HIGH to Data Valid
-
10
tCHWEL
XCLK HIGH to WE LOW
-
10
tCHHBLSL
XCLK HIGH to BLS LOW
-
10
tAVCSL
XCLK HIGH to WE HIGH
-
10
tAVCSL
XCLK HIGH to BLS HIGH
-
10
tAVCSL
XCLK HIGH to Data Invalid
-
10
[1] Except on initial access, in which case the address is set up tCYC earlier.
Unit
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
9397 750 13149
Product data
Rev. 02 — 23 December 2004
© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
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