PIN FUNCTIONS
VCC (Pin 1): Positive Supply. 4.75V < VCC < 5.25V.
R (Pin 2): Receiver Output. R is high if (A – B) ≥ – 10mV
and low if (A – B) ≤ – 200mV.
D (Pin 3): Driver Input. If D is high, Y is taken high and Z
is taken low. If D is low, Y is taken low and Z is taken high.
GND (Pin 4): Ground.
Y (Pin 5): Driver Output.
Z (Pin 6): Driver Output.
B (Pin 7): Receiver Input.
A (Pin 8): Receiver Input.
LTC1690
TEST CIRCUITS
Y
VOD2
Z
R
R VOC
1690 F01
Figure 1. Driver
DC Test Load #1
375Ω
Y
VOD3
Z
60Ω
375Ω
VTST
–7V TO 12V
1690 F02
Figure 2. Driver
DC Test Load #2
UW
W
SWITCHI G TI E WAVEFOR S
3V
D
0V
VO
–VO
Z
VO
Y
1.5V
50%
10%
tr
tSKEW
f = 1MHz, tr ≤ 10ns, tf ≤ 10ns
tPLH
90%
VO = V(A) – V(B)
1/2 VO
1.5V
tPHL
90%
50%
10%
tf
tSKEW
1690 F04
Figure 4. Driver Propagation Delays
+
Y
CL1 A
D
RDIFF
Z
+
CL2 B
Figure 3. Driver/Receiver
Timing Test Load
R
+
15pF
1690 F03
VOD2
A–B
0V
–VOD2
5V
f = 1MHz, tr ≤ 10ns, tf ≤ 10ns
INPUT
0V
tPHL
R
1.5V
OUTPUT
VOL
NOTE: tSKD = |tPHL – tPLH|
tPLH
1.5V
1690 F05
Figure 5. Receiver Propagation Delays
FUNCTION TABLES
Driver
D
Z
Y
1
0
1
0
1
0
Receiver
A–B
R
≥ – 0.01V
1
≤ – 0.20V
0
Inputs Open
1
Inputs Shorted
1
Note: Table valid with or without termination resistors.
7