Robert L Gruebel

US Patent:

50476726, Sep 10, 1991

Filed:

Mar 31, 1989

Appl. No.:

7/332257

Inventors:

Rohit L. Bhuva - Plano TX
Walter C. Bonneau - Peoria AZ
Robert L. Gruebel - Plano TX
Robert A. Helmick - Allen TX
Allen Y. Chen - Plano TX

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

H03K 190175
H03K 1920
H03K 1716
G06F 738

US Classification:

307475

Abstract:

A circuit (90) converts a true ECL signal to a true TTL signal. The circuit includes a differential circuit (180) that receives an ECL signal having high and low values. The differential circuit produces a differential signal therefrom that has a high value in response to one of the high and low values of the true ECL signal, and a low value in response to the other of the high and low values of the true ECL signal. A first translator circuit (36, 64) has an input (32) coupled to the differential circuit (180). The first translator circuit (36, 64) transmits a true low TTL output (56) signal having a voltage level referenced to the voltage level of a TTL low supply voltage in response to receiving a high value of the differential signal. A second translator circuit (46, 52) has an input (38) and is coupled to a TTL high supply voltage and the output (56). An input signal appearing on the input (38) of the second translator circuit has a voltage level related to the voltage level of the differential signal (32).