公开(公告)号：GB1207276A

公开(公告)日：1970-09-30

申请号：GB5674368

申请日：1968-11-29

Applicant: MOTOROLA INC

Inventor： SOLOMON JAMES E ,  DAVIS WALTER RICHARD

IPC: H03G1/00

Abstract: 1,207,276. Transistor automatic gain control circuits. MOTOROLA Inc. 29 Nov. 1968 [29 Jan., 1968], No. 56743/68. Headings H3T and H4R. A gain control circuit comprises a first pair of transistors 40, 42, Fig. 2, with the collectoremitter path of a further transistor 48 as common emitter load, together with a second pair of transistors 44, 46 with the collector-emitter path of transistor 50 as common emitter load. Signals to be amplified are applied in push-pull to the bases of transistors 48, 50 the emitter circuits of which comprise a T-network of resistors 56, 58, 60: a push pull output is derived from the collectors of transistors 40, 46. Gain control signals are applied via terminals 52 between the bases of transistors 42, 44 and 40, 46 the arrangement being such that decoupling capacitors for the signal frequency are not necessary. In a modification transistors 48, 50, Fig. 4, are driven by means of a transformer 49 with equal series-connected secondary circuit resistors 51, 53, the emitter circuit being replaced by a # network of resistors 70, 72, 74. A temperature - compensated power supply is derived from a potentiometer network comprising resistors 71, 73, 114, 116 and transistors 85, 87 strapped as diodes: the collector supply for transistors 40, 46 is taken off via transistors 75, 76 and their base supply via a further transistor 77. Base bias for transistors 48, 50 is derived over transistor 179. Transistors 40, 46 drive an output stage comprising transistors 86, 88 and a pair of emitter-followers 82, 84: transistors 82, 84, 86, 88 are provided with a common emitter impedance comprising transistors 90,92 in Darlington connection. The transistors 90, 92 are biased from a potentiometer network comprising resistors 89, 91 and transistors 85, 87 strapped as diodes.

公开(公告)号：GB1133670A

公开(公告)日：1968-11-13

申请号：GB5036367

申请日：1967-11-06

Applicant: MOTOROLA INC

Inventor： SOLOMON JAMES E

IPC: H03G1/00 ,  H03G5/28 ,  H03H11/12

Abstract: 1,133,670. Variable bandwidth filter. MOTOROLA Inc. 6 Nov., 1967 [14 Dec., 1966], No. 50363/67. Heading H3T. A variable bandwidth filter comprises an amplifier with overall negative feedback, the bandwidth being varied without variation of gain by variation of the gain in the forward transmission path. In a low-pass embodiment, the forward path comprises a transistor 40 in common base connection, its input circuit comprising shunt R.C. circuit 30, 32 and series resistance 63 and capacitor 34, while the output circuit comprises a second shunt R.C. circuit 46, 45. The negative feedback path comprises a second transistor 52 in common emitter connection, in addition to a decoupled bias resistor 56 an undecoupled resistor 54 is provided to stabilize the gain. The gain of the forward path-which is always kept several times greater than unity in order that the overall gain may not appreciably vary-is varied, and with it the bandwidth, by means of diode 23 to which a control voltage is applied via terminal 22: variation of the diode bias varies the partition of the current through resistor 36 between the diode and the emitter of transistor 40, thereby varying the transistor gain without variation of the effective input impedance. The Specification includes a mathematical exposition of the mode of operation of the invention.

公开(公告)号：GB1276375A

公开(公告)日：1972-06-01

申请号：GB5298869

申请日：1969-10-29

Applicant: MOTOROLA INC

Inventor： SOLOMON JAMES E

IPC: H03F1/48 ,  H03F3/45

Abstract: 1276375 Transistor amplifying circuits MOTOROLA Inc 29 Oct 1969 [22 Nov 1968] 52988/69 Heading H3T In a transistor differential amplifier (Fig. 4) the base-emitter junctions of output transistors 12, 14 are connected across the collector-emitter paths of complementary type input transistors 10, 16. This permits low input currents and zero collector-base voltage for transistors 10, 16 to eliminate collector-base leakage and renders the output current of transistors 12; 14 independent of their # value. In Fig. 4, the arrangement is supplied from current sources 56, 58, 68 althrough separate or common sources may be used for the two collector-base connections or the two emitter-base connectors (Figs. 3-6, not-shown) 60, 62 provide positive feedback to minimize signal propagation time and resistors (82, 84, Fig. 6, not shown) may be connected to the emitters of transistors 12, 14 to minimize overshoot and maximize rise time. In Fig. 7, transistors 10, 12, 14, 16 are supplied from constant current sources 86, 90, 92. An input signal for a second amplifier stage 23 is derived from the difference in output signals of 12, 14 in a circuit comprising transistors 98- 102. Common mode signals are thus eliminated. A Miller capacitor 136 provides frequency compensation for stage 23 by reducing its output impedance at high frequencies. A transistor 122 provides a voltage drop to reduce the quiescent current through the class A, B outputstage 25 to about one fifth of that through transistors 122 126. Transistors 124, 126 provide temperature compensation for output transistors 154, 156. To protect the amplifier from shorting of the output terminal to ground diodes 144, 146 are provided. For positive going shorts, the output current is limited to that supplied by transistor 118 through diode- 146. For negative going shorts, a transistor 134 is turned on, to turn off transistor 128 and hold transistor 130 in a constant current condition, the current being conducted through diode 144. Transistors 85 and 87 provide overvoltage protection for the input amplifier.

公开(公告)号：CA789700A

公开(公告)日：1968-07-09

申请号：CA789700D

Applicant: MOTOROLA INC

Inventor： SOLOMON JAMES E ,  THOMPSON JAMES E

公开(公告)号：CA843568A

公开(公告)日：1970-06-02

申请号：CA843568D

Applicant: MOTOROLA INC

Inventor： SOLOMON JAMES E

公开(公告)号：CA768303A

公开(公告)日：1967-09-26

申请号：CA768303D

Applicant: MOTOROLA INC

Inventor： NARUD JAN A ,  SOLOMON JAMES E