Bi-directional buffer for interfacing test system channel
First Claim
1. A probe card apparatus comprising:
- a plurality of electrical connections to a tester for testing an electronic device;
a plurality of probes disposed to contact the electronic device;
a plurality of communications channels connecting ones of the electrical connections to ones of the probes; and
in a first one of the communication channels, a first amplifier for amplifying a signal output by the electronic device and received at a first one of the probes, the first amplifier providing the amplified signal to a first one of the electrical connections, anda first by-pass resistor providing a resistive electrical path to the first of the probes by-passing the first amplifier for test signals output by the tester and received at the first one of the electrical connections, wherein;
the first amplifier is biased such that the first amplifier is off in response to a signal driven through the first one of the electrical connections to the first one of the probes, andthe first amplifier is biased such that the first amplifier is on in response to a signal driven through the first one of the probes to the first one of the electrical connections.
1 Assignment
0 Petitions
Accused Products
Abstract
An emitter follower or source follower transistor is provided in the channel of a wafer test system between a DUT and a test system controller to enable a low power DUT to drive a test system channel. A bypass resistor is included between the base and emitter of the emitter follower transistor to enable bi-directional signals to be provided between the DUT channel and test system controller, as well as to enable parametric tests to be performed. The emitter follower transistor and bypass resistor can be provided on the probe card, with a pull down termination circuit included in the test system controller. The test system controller can provide compensation for the base to emitter voltage drop of the emitter follower transistor.
27 Citations
16 Claims
-
1. A probe card apparatus comprising:
-
a plurality of electrical connections to a tester for testing an electronic device; a plurality of probes disposed to contact the electronic device; a plurality of communications channels connecting ones of the electrical connections to ones of the probes; and in a first one of the communication channels, a first amplifier for amplifying a signal output by the electronic device and received at a first one of the probes, the first amplifier providing the amplified signal to a first one of the electrical connections, and a first by-pass resistor providing a resistive electrical path to the first of the probes by-passing the first amplifier for test signals output by the tester and received at the first one of the electrical connections, wherein; the first amplifier is biased such that the first amplifier is off in response to a signal driven through the first one of the electrical connections to the first one of the probes, and the first amplifier is biased such that the first amplifier is on in response to a signal driven through the first one of the probes to the first one of the electrical connections. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A probe card apparatus comprising:
-
a plurality of electrical connections to communications channels to a tester for testing an electronic device; a plurality of probes disposed to contact the electronic device; in a first communication channel, a first amplifier for amplifying a signal output by the electronic device and received at a first of the probes, the first amplifier providing the amplified signal to a first of the communications channels; a first by-pass electrical path for providing an electrical path to the first of the probes by-passing the first amplifier for test signals output by the tester and received at the first connection to the first of the communications channels; a temperature sensor; and a power supply circuit connected to the temperature sensor, the power supply circuit providing a voltage to the first amplifier that varies with a temperature sensed by the temperature sensor. - View Dependent Claims (9)
-
-
10. A method of testing an electronic device, the method comprising:
-
providing a plurality of test signals from a tester for controlling testing of the electronic device through a probe card apparatus comprising a plurality of communications channels between the tester and the electronic device, the providing comprising providing one of the test signals through a first by-pass resistor by-passing an amplifier disposed in a first one of the communications channels to a first probe in contact with the electronic device; and amplifying an output signal output by the electronic device and received at the first probe with the amplifier to produce an amplified signal; and providing the amplified output signal to the tester through the first communications channel, wherein the first by-pass resistor by-passes the first amplifier. - View Dependent Claims (11, 12, 13, 14, 15)
-
-
16. A method of testing an electronic device, the method comprising:
-
providing a plurality of test signals from a tester for controlling testing of the electronic device through ones of communications channels between the tester and the electronic device, the providing comprising providing one of the test signals through a first by-pass path of a first of the communications channels to a first probe in contact with the electronic device; amplifying an output signal output by the electronic device and received at the first probe; providing the amplified output signal to the tester through the first communications channel, wherein the first by-pass path by-passes the first amplifier; sensing a temperature adjacent the first amplifier; and varying a voltage component of power supplied to the first amplifier in accordance with the sensed temperature.
-
Specification