Abstract:
A frequency divider divides a frequency of a DLL clock CLK_P into two, to generate ZCLK_PD0 and ZCLK_PD1. A delay circuit generates ZCLK_PDD0, ZCLK_PDD1 obtained by delaying ZCLK_PD0, ZCLK_PD1 respectively by Tc (=a backward amount of CLK_P with respect to an external clock+a delay amount of an internal clock with respect to the external clock). A frequency division select instruction circuit generates ZSEL0, ZSEL1 based on an internal clock CLK, and ZCLK_PDD0, PDD1. A ZSEL0 shifter circuit generates ZSEL1_D2 including a clock pulse of ZSEL1. A ZCLK_P #2 select circuit selects a clock pulse of ZCLK_PD0 using ZSEL1_D2.
Abstract:
An anode lead 17 extending from a capacitor body 18 of a capacitor element 14 is mounted on a connecting portion 21 of an anode terminal 12 and the anode lead 17 and the connecting portion 21 are welded together by laser light B. The welding operation is performed by laser light B in a state where the anode lead 17 is urged to the connecting portion 21 in a region between said anode lead and said connecting portion. Alternatively, the welding operation is performed by laser light B in a state where a reflection plate having a slot and functioning to reflect reflected laser light is arranged in a region between the connecting portion and the capacitor body while the anode lead is received in said slot.
Abstract:
In the case where memory arrays are arranged so as to surround the central region where peripheral circuitry and pads are provided, arranging pads for receiving addresses A0 to A12, BA1 and BA0 in two trains is facilitated. By locating an address latch circuit at an equal distance from each pad train, characteristics of the setup time and hold time can be improved.
Abstract:
A chip capacitor has capacitor component 14 having anode lead 17 and sintered body 21 of a metal having a valve action in which anode lead 17 is embedded so as to project from embedding surface 21a, resin-based insulating film layer 24 containing a white pigment and disposed on the embedding surface of capacitor component 14, water-repellent layer 25 disposed on resin-based insulating film layer 24, anode terminal 12 having a portion bent into joint tongue 31, with anode lead 17 being placed on joint tongue 31, joint tongue 31 and anode lead 17 being welded to each other into anode terminal 12, and antireflection member 34 extending from a proximal end of joint tongue 31 of anode terminal 12 toward sintered body 21. When joint tongue 31 and anode lead 17 are welded to each other by a laser beam, antireflection member 34 prevents the laser beam from being reflected from the welded region.
Abstract:
According to a reference voltage generated by a reference voltage generating circuit, a level shift circuit generates a control voltage with its level shifted from the reference voltage by a threshold voltage of a difference detection transistor. According to this control voltage, the difference detection transistor operates in a source follower mode to adjust a charged voltage of a capacitance element according to a voltage level of an internal voltage line. A current is supplied from a current drive circuit to the internal voltage line according to the charged voltage. In this way, an internal voltage is generated having a constant voltage level over a wide temperature range with a small occupying area and a small current consumption.
Abstract:
A through-current Ic of a comparator circuit is switched in accordance with a response speed required with respect to a current consumption. Additionally, a through-current Is of a shifter circuit, which sends to the comparator circuit an output signal at an appropriate level transmitting a difference between an internal power supply potential Vdd and a reference potential Vref is switched according to the required response speed. When a device is in a standby state requiring a small current consumption in internal power supply potential Vdd, both through-currents Ic and Is are set small so that the whole current consumption can be further reduced.
Abstract:
The amount of charge supplied to a high level sense power supply line by a level control circuit is monitored. Charge of an equal amount is drawn out from a low level sense power supply line according to the monitoring result. In a memory of a boosted sense ground scheme, the boosted sense ground voltage can be maintained at a predetermined voltage level stably.
Abstract:
A Vpp level detecting circuit detects a potential on a Vpp trunk line which is provided commonly to a plurality of memory array banks for supplying a boosted potential thereto, and a boosted potential pump circuit supplies a current to the Vpp trunk line in accordance with a result of the detection. Since the position on the Vpp trunk line where the Vpp level detecting circuit performs the monitoring is substantially equally spaced from the respective memory blocks, an influence caused by an active state of the memory array bank can be suppressed during control of the potential on the Vpp trunk line.
Abstract:
In order to stably generate a high voltage of a prescribed level, a Vpp detection circuit which is activated in response to an activation signal for comparing the high voltage with a reference voltage is forcibly brought into an active state for a prescribed period under control of an initial control circuit.
Abstract:
A circuit for supplying a stress to memory cells of a semiconductor memory device having the plurality of the memory cells respectively connected to a word line and a bit line comprises a circuit for generating precharge voltage for bit line, a bit line precharging and equalizing circuit which is connected between said circuit for generating precharge voltage for bit line and said memory cells, a pad connected to the bit line precharging and equalizing circuit for applying a desirable voltage to said memory cells through the corresponding bit lines, and a circuit connected to the circuit for generating precharge voltage for bit line for generating a signal for stopping the operation of said circuit for generating precharge voltage for bit line, whereby cell checker patterns can easily be realized in order to screen out possible failures not only in gate oxide films but also in capacitor dielectrics, storage node junctions or the like by applying an arbitrary stress voltage from the outside of the device.