74HC40105D,652

74HC40105 4-bit x 16-word FIFO register Rev. 5 19 April 2019 Product data sheet 1. General description The 74HC40105 is a first-in/first-out (FIFO)elasti storage register that can store 16 4-bit words. It can handle input and output data at different shifting rates. This feature makes it particularly useful as a buffer between asynchronous systems. Each word position in the register is clocked by a control flip-flop, which stores a marker bit. A logic 1 signifies that the data at that position is filled and a logic 0 denotes a vacancy in that position. The control flip-flop detects the state of the preceding flip-flop and communicates its own status to the succeeding flip-flop. When a control flip-flop is in the logic 0 state and sees a logic 1 in the preceding flip-flop, it generates a clock pulse. The clock pulse transfers data from the preceding four data latches into its own four data latches and resets the preceding flip-flop to logic 0. The first and last control flip-flops have buffered outputs. All empty locationsbubbl automatically to the input end, and all valid data ripples through to the output end. As a result, the status of the first control flip-flop (data-in ready output - DIR) indicates if the FIFO is full. The status of the last flip-flop (data-out ready output - DOR) indicates whether the FIFO contains data. As the earliest data is removed from the bottom of the data stack (output end), all data entered later will automatically ripple toward the output. Inputs include clamp diodes that enable the use of current limiting resistors to interface inputs to voltages in excess of V . CC 2. Features and benefits Independent asynchronous inputs and outputs Expandable in either direction Reset capability Status indicators on inputs and outputs 3-state outputs CMOS input levels Complies with JEDEC standard JESD7A ESD protection: HBM JESD22-A114F exceeds 2000 V MM JESD22-A115-A exceeds 200 V Specified from -40 C to +85 C and from -40 C to +125 C 3. Ordering information Table 1. Ordering information Type number Package Temperature range Name Description Version 74HC40105D -40 C to +125 C SO16 plastic small outline package 16 leads SOT109-1 body width 3.9 mmNexperia 74HC40105 4-bit x 16-word FIFO register 4. Functional diagram 1 FIFO 16 x 4 1 2 EN6 IR 2 14 1Z2 OR 5 OE 4 D0 Q0 13 CTR 3 1 (+/C4) 5 D1 Q1 12 CT < 16 G1 9 CT = 0 G3 CT > 0 6 D2 Q2 11 15 3 - 7 D3 Q3 10 3Z5 4 13 4D 6 3 SI DOR 14 5 12 15 SO DIR 2 6 11 MR 7 10 aaa-008737 9 aaa-008736 Fig. 2. IEC logic symbol Fig. 1. Logic symbol 4 D0 Q0 13 5 D1 Q1 12 4 x 16 6 D2 Q2 11 DATA REGISTER Q3 10 7 D3 1 OE DOR 14 2 DIR CONTROL LOGIC SO 15 3 SI MR 9 aaa-008738 Fig. 3. Functional diagram 74HC40105 All information provided in this document is subject to legal disclaimers. Nexperia B.V. 2019. All rights reserved Product data sheet Rev. 5 19 April 2019 2 / 27