U2739M-BFT Atmel, U2739M-BFT Datasheet - Page 23

• Manufacturer Part Number: U2739M-BFT
• Description: IC DECODER 1CHAN/SOURCE 100-PQFP
• Manufacturer: Atmel
• Type: Decoderr

Specifications of U2739M-BFT

• Applications: Processing, IF Modules
• Mounting Type: Surface Mount
• Package / Case: 100-MQFP, 100-PQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

6.6.4
6.7
6.7.1
6.7.2
The U2739M-B master clock should be derived from a voltage-controlled reference oscillator. The pulse width modu-
lated output signal PWM of the U2739M-B can be used to control the VCXO frequency of 24.576 MHz.
Rev. A1, 22-May-01
Read/ write cycle time
Output delay SRAM_A(18:0)
Output delay SRAM_WR
Output delay SRAM_OE
Setup time SRAM_D(7:0)
Write pulse with
Output delay SRAM_D(7:0)
Data valid to end of write
QFP144 QFP100
19
20
21
22
25
U2739M-B
VCXO Interface
SRAM Interface Timing Parameter
VCXO Interface Signal Description
VCXO Interface Description
PWM
PAD
13
14
15
16
18
Parameter
AVSS1
XIN
XOUT
AVDD1
PWM
Pin Name
f
n = 11 –> f
PWM
= f
PAD
XIN
Analog ground
Oscillator input
Oscillator output
Analog power supply
Pulse width modulated control output
clk2457
Figure 12. VCXO application circuit
VCXO 24.576 MHz
PWM
/ 2
= 12 kHz
n
Signal Description
Symbol
tddata
tdvwh
tsdata
tavav
twleh
td1
td2
td3
XOUT
PAD
Min.
15.0
12.0
16.0
33.0
15.0
33.0
2.0
Typ.
40.7
25.0
20.0
24.0
40.7
23.0
40.7
PVSS3Z
PDX02
(PDX02)
PVDD3Z
PRO04T
Pad Type
PLL
U2739M-B
Max.
35.0
28.0
32.0
48.0
31.0
48.0
49.192 MHz
Dir.
pwr
gnd
osc
osc
out
5 V Tol.
Unit
23 (69)
ns
ns
ns
ns
ns
ns
ns
ns
x