Elenco Electronics LP-700 Specifications

Logic Probe LP-700 Specifications

Elenco Electronics, Inc. Wheeling, IL 60090

Max. Ratings

Maximum allowable supply voltage +25V
Guaranteed operating supply voltage range 3 ~ 18V
Maximum input voltage +50V
Guaranteed operating input voltage range –25 ~ +25V
Free-Air operating temperature range 0 ~ 50

O

C

Storage temperature range –65 ~ +150OC

Specifications

a. Input Impedance 120kW
b. Minimum detectable pulse width

1. At Vcc = 5 Volts 20ns

2. At Vcc>10 Volts 20ns

c. Logic Thresholds

TTL CMOS

Logic 1 (green LED lights) 2.3 +

0.2V 70% Vcc +1V

Logic 0 (green LED off) 0.8 + 0.2V 30% Vcc +1V
High impedance >500kW >1MW
(green LED blinks at a frequency of 1Hz)
Excessive Vcc supply voltage (red LED lights) Vcc +5V

Minus voltage (orange LED lights) –5V
d. Max input frequency displayable 20MHz
e. Input overvoltage protection +

50V/10 sec

+240V AC/1 sec
f. Pulse LED (yellow) flashing time 200ms
g. Power supply protection +25V/10 sec
h. Size 0.62Æ x 6.8”
i. Weight 1.8 oz.

Operating Instructions

A. Setting up the instrument

a. Applying power to the probe

1. Connect the black clip to GND (–).

2.

Connect the red clip to Vcc (+). Be sure Vcc is less than 25V, (Vcc = 5V in TTL circuit. Vcc = 3~18V in CMOS circuit).

3. If the supply voltage is correct, the green LED will blink. The yellow LED lights indicating the supply voltage
is over 25 volts, the orange and red LED lights indicating the supply voltage is the wrong polarity. Please
remove the clips quickly.

b. Setting the switches

1. TTL/CMOS switch
The TTL/CMOS switch can be switched to TTL mode for use in the TTL circuit. The TTL logic 1 is >2.3V,
Logic 0 is <0.8V. When switched to CMOS mode for CMOS circuit, the CMOS logic 1 is >70% Vcc, logic
0 is <

30% Vcc. At the same time, the switch can determine if the pulse modes trigger edge is positive or

is negative. This is very useful when you have the LP-600 Logic Pulser, and try to test the IC truth table.

2. Pulse/Memory Switch
The logic probe can detect and memorize the level transition. Either positive or negative level transition can
be detected or memorized, depending on the mode selected.
(a) Pulse position: The memory function is inoperative in this position. Input state transition is “0” to “1” or “1”
to “0”, will activate the pulse indicator for 200ms.
(b) Memory position: In this position, memory function is activated. Pulse indicator lights up until reset if any
pulse or level transition occurs.
NOTE: The probe tip must be first connected to the node and then the selecting switch set to memory

position. Otherwise a false read out will occur, because the level transition may be falsely activated
when a floating tip is connected to the node.

B. TYPICAL signals and corresponding LED indication:

P1

=

=

=