MOTOROLA
SEMICONDUCTOR TECHNICAL DATA
68030/040 PECL-TTL Clock Driver
The MC10H/100H642 generates the necessary clocks for the 68030,
68040 and similar microprocessors. It is guaranteed to meet the clock
specifications required by the 68030 and 68040 in terms of part–to–part
skew, within–part skew and also duty cycle skew.
The user has a choice of using either TTL or PECL (ECL referenced to
+5.0V) for the input clock. TTL clocks are typically used in present MPU
systems. However, as clock speeds increase to 50MHz and beyond, the
inherent superiority of ECL (particularly differential ECL) as a means of
clock signal distribution becomes increasingly evident. The H642 also
uses differential PECL internally to achieve its superior skew
characteristic.
The H642 includes divide–by–two and divide–by–four stages, both to
achieve the necessary duty cycle skew and to generate MPU clocks as
required. A typical 50MHz processor application would use an input clock
running at 100MHz, thus obtaining output clocks at 50MHz and 25MHz
(see Logic Diagram).
The 10H version is compatible with MECL 10H ECL logic levels,
while the 100H version is compatible with 100K levels (referenced to
+5.0V).
• Generates Clocks for 68030/040
• Meets 030/040 Skew Requirements
• TTL or PECL Input Clock
• Extra TTL and PECL Power/Ground Pins
• Asynchronous Reset
• Single +5.0V Supply
MC10H642
MC100H642
68030/040
PECL–TTL CLOCK
DRIVER
26
45
FN SUFFIX
PLASTIC PACKAGE
CASE 776–02
11
Function
Reset(R):
Select(SEL):
LOW on RESET forces all Q outputs LOW.
LOW selects the ECL input source (DE/DE).
HIGH selects the TTL input source (DT).
The H642 also contains circuitry to force a stable input state of the ECL differential input pair , should both sides be left open. In
this Case, the DE side of the input is pulled LOW, and DE
Power Up:
The device is designed to have positive edges of the ÷2 and ÷4 outputs synchronized at Power Up.
VT VT Q1 GT GT Q0 VT
25 24 23 22 21 20 19
Q2
26
GT
27
GT
28
Pinout: 28–Lead PLCC
567891011
Q5
GT GT Q6 Q7 VT SEL
VT
VT
Q3
1
2
3
4
goes HIGH.
(Top View)
18
V
BB
17
DE
16
DE
VE
15
R
14
GE
13
12
DTQ4
9/96
Motorola, Inc. 1996
2–1
REV 4
MC10H642 MC100H642
LOGIC DIAGRAM
TTL Outputs
Q7
TTL/ECL Clock Inputs
V
BB
DE
DE
DT
SEL
TTL Control Inputs
R
MUX
÷4
÷2
Q6
Q5
Q4
Q3
Q2
Q1
Q0
PIN NAMES
Pin Symbol Description Pin Symbol Description
81
82
83
84
85
86
87
88
89
10
11
12
13
14
**Divide by 2
**Divide by 4
Q3
VT
VT
Q4
Q5
GT
GT
Q6
Q7
VT
SEL
DT
GE
R
Signal Output (TTL)**
TTL VCC (+5.0V)
TTL VCC (+5.0V)
Signal Output (TTL)**
Signal Output (TTL)**
TTL Ground (0V)
TTL Ground (0V)
Signal Output (TTL)**
Signal Output (TTL)**
TTL VCC (+5.0V)
Input Select (TTL)
TTL Signal Input
ECL Ground (0V)
Reset (TTL)
15
16
17
18
19
20
21
22
23
24
25
26
27
28
V
VE
DE
DE
BB
VT
Q0
GT
GT
Q1
VT
VT
Q2
GT
GT
ECL VCC (+5.0V)
ECL Signal Input (Non–Inverting)
ECL Signal Input (Inverting)
VBB Reference Output
TTL VCC (+5.0V)
Signal Output (TTL)*
TTL Ground (0V)
TTL Ground (0V)
Signal Output (TTL)*
TTL VCC (+5.0V)
TTL VCC (+5.0V)
Signal Output (TTL)**
TTL Ground (0V)
TTL Ground (0V)
MOTOROLA MECL Data
2–2
DL122 — Rev 6
MC10H642 MC100H642
AC CHARACTERISTICS (VT = VE = 5.0V ±5%)
TA = 0°C TA = 25°C TA = 85°C
Symbol Characteristic Min Max Min Max Min Max Unit Condition
t
PLH
tskpp Part–to–Part Skew 1.0 1.0 1.0 ns
tskwd* Within–Device Skew 0.5 0.5 0.5 ns
t
PLH
tskpp Part–to–Part Skew All
tskwd Within–Device Skew 1.0 1.0 1.0 ns CL = 25pF
t
PD
t
R
t
F
f
MAX
RPW Reset Pulse Width 1.5 1.5 1.5 ns
RRT Reset Recovery Time 1.25 1.25 1.25 ns
* Within–Device Skew defined as identical transactions on similar paths through a device.
** NOTE: MAX Frequency is 135MHz.
Propagation Delay
D to Output
Propagation Delay
D to Output
Propagation Delay
R to Output
Output Rise/Fall Time
0.8 V to 2.0 V
** Maximum Input Frequency 100 100 100 MHz CL = 25pF
Q2–Q7
C ECL
C TTL
Q0, Q1
C ECL
C TTL
Outputs
All
Outputs
All
Outputs
4.70
4.70
4.30
4.30
4.3 6.3 4.0 6.0 4.5 6.5 ns CL = 25pF
5.70
5.70
5.30
5.30
2.0 2.0 2.0 ns CL = 25pF
2.5
2.5
4.75
4.75
4.50
4.50
5.75
5.75
5.50
5.50
2.5
2.5
4.60
4.50
4.25
4.25
5.60
5.50
5.25
5.25
2.5
2.5
ns CL = 25pF
ns CL = 25pF
ns CL = 25pF
10H PECL CHARACTERISTICS (VT = VE = 5.0V ±5%)
TA = 0°C TA = 25°C TA = 85°C
Symbol Characteristic Min Max Min Max Min Max Unit Condition
I
IH
I
IL
V
IH
V
IL
V
BB
Input HIGH Current
Input LOW Current
* NOTE
Input HIGH Voltage
Input LOW Voltage
* NOTE
Output Reference Voltage 3.62 3.73 3.65 3.75 3.69 3.81 V
0.5
3.83
3.05
225
4.16
3.52
0.5
3.87
3.05
175
4.19
3.52
0.5
3.94
3.05
175 µA
4.28
3.555
V VEE = 5.0V
100H PECL CHARACTERISTICS (VT = VE = 5.0V ±5%)
TA = 0°C TA = 25°C TA = 85°C
Symbol Characteristic Min Max Min Max Min Max Unit Condition
I
IH
I
IL
V
IH
V
IL
V
BB
*NOTE: PECL LEVELS are referenced to VCC and will vary 1:1 with the power supply. The VALUES shown are for VCC = 5.0V.
Input HIGH Current
Input LOW Current
* NOTE
Input HIGH Voltage
Input LOW Voltage
* NOTE
Output Reference Voltage 3.620 3.740 3.620 3.740 3.620 3.740 V
0.5
3.835
3.190
225
4.120
3.525
0.5
3.835
3.190
175
4.120
3.525
0.5
3.835
3.190
175 µA
4.120
3.525
V VEE = 5.0V
DL122 — Rev 6
2–3 MOTOROLAMECL Data