74HC299D,653 Nexperia

74HC299 8-bit universal shift register 3-state Rev. 6 11 May 2021 Product data sheet 1. General description The 74HC299 is an 8-bit universal shift register with 3-state outputs. It contains eight edge-triggered D-type flip-flops and the interstage logic necessary to perform synchronous shift-right, shift-left, parallel load and hold operations. The type of operation is determined by the mode select inputs S0 and S1. Pins I/O0 to I/O7 are flip-flop 3-state buffer outputs which allow them to operate as data inputs in parallel load mode. The serial outputs Q0 and Q7 are used for expansion in serial shifting of longer words. A LOW signal on the asynchronous master reset input MR overrides the Sn and clock CP inputs and resets the flip-flops. All other state changes are initiated by the rising edge of the clock pulse. Inputs can change when the clock is either state, provided that the recommended set-up and hold times are observed. A HIGH signal on the 3-state output enable inputs OE1 or OE2 disables the 3-state buffers and the I/On outputs assume a high-impedance OFF-state. In this condition, the shift, hold, load and reset operations can still occur. The 3-state buffers are also disabled by HIGH signals on both S0 and S1, when in preparation for a parallel load operation. Inputs include clamp diodes. This enables the use of current limiting resistors to interface inputs to voltages in excess of V . CC 2. Features and benefits CMOS input levels Multiplexed inputs/outputs provide improved bit density Four operating modes: Shift left Shift right Hold (store) Load data Operates with output enable or at high-impedance OFF-state 3-state outputs drive bus lines directly Cascadable for n-bit word lengths 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 74HC299D -40 C to +125 C SO20 plastic small outline package 20 leads SOT163-1 body width 7.5 mmNexperia 74HC299 8-bit universal shift register 3-state 4. Functional diagram 1 19 S0 S1 DSL DSR 11 18 CP 12 8-BIT SHIFT REGISTER MR 9 Q0 Q7 8 17 OE1 2 INPUT/3-STATE OUTPUT CIRCUITRY OE2 3 I/O0 I/O1 I/O2 I/O3 I/O4 I/O5 I/O6 I/O7 7 13 6 14 5 15 4 16 001aai460 Fig. 1. Functional diagram 9 R SRG8 2 & 3EN5 3 1 0 0 M 19 1 3 12 C4/1 /2 11 1, 4D 1 I/O0 7 S0 7 8 Z6 3, 4D 19 S1 I/O1 13 6, 5 13 11 I/O2 6 DSR 3, 4D 5 18 DSL I/O3 14 6 I/O4 5 14 12 CP I/O5 15 5 15 I/O6 4 9 MR 4 I/O7 16 16 2 3, 4D OE Q0 8 17 3 7, 5 Z7 18 Q7 17 2, 4D 001aai458 001aai459 Fig. 2. Logic symbol Fig. 3. IEC logic symbol 74HC299 All information provided in this document is subject to legal disclaimers. Nexperia B.V. 2021. All rights reserved Product data sheet Rev. 6 11 May 2021 2 / 15