| 666921 | HEF4008BP | 4-bit binary full adder | Philips |
| 666922 | HEF4008BT | 4-bit binary full adder | Philips |
| 666923 | HEF40097 | 3-state hex non-inverting buffer | Philips |
| 666924 | HEF40097B | 3-state hex non-inverting buffer | Philips |
| 666925 | HEF40097BD | 3-state hex non-inverting buffer | Philips |
| 666926 | HEF40097BF | 3-state hex non-inverting buffer | Philips |
| 666927 | HEF40097BN | 3-state hex non-inverting buffer | Philips |
| 666928 | HEF40097BP | 3-state hex non-inverting buffer | Philips |
| 666929 | HEF40097BT | 3-state hex non-inverting buffer | Philips |
| 666930 | HEF40098B | 3-state hex inverting buffer | Philips |
| 666931 | HEF40098BD | 3-state hex inverting buffer | Philips |
| 666932 | HEF40098BF | 3-state hex inverting buffer | Philips |
| 666933 | HEF40098BN | 3-state hex inverting buffer | Philips |
| 666934 | HEF40098BP | Hex inverting buffer; 3-state | NXP Semiconductors |
| 666935 | HEF40098BP | 3-state hex inverting buffer | Philips |
| 666936 | HEF40098BT | Hex inverting buffer; 3-state | Nexperia |
| 666937 | HEF40098BT | Hex inverting buffer; 3-state | NXP Semiconductors |
| 666938 | HEF40098BT | 3-state hex inverting buffer | Philips |
| 666939 | HEF40106 | Hex inverting Schmitt trigger | Philips |
|
| 666940 | HEF40106B | Hex inverting Schmitt trigger | Philips |
| 666941 | HEF40106BD | Hex inverting Schmitt trigger | Philips |
| 666942 | HEF40106BF | Hex inverting Schmitt trigger | Philips |
| 666943 | HEF40106BN | Hex inverting Schmitt trigger | Philips |
| 666944 | HEF40106BP | Hex inverting Schmitt trigger | NXP Semiconductors |
| 666945 | HEF40106BP | Hex inverting Schmitt trigger | Philips |
| 666946 | HEF40106BT | Hex inverting Schmitt trigger | Nexperia |
| 666947 | HEF40106BT | Hex inverting Schmitt trigger | NXP Semiconductors |
| 666948 | HEF40106BT | Hex inverting Schmitt trigger | Philips |
| 666949 | HEF40106BT-Q100 | Hex inverting Schmitt trigger | Nexperia |
| 666950 | HEF40106BT-Q100 | Hex inverting Schmitt trigger | NXP Semiconductors |
| 666951 | HEF40106BTT | Hex inverting Schmitt trigger | Nexperia |
| 666952 | HEF40106BTT | Hex inverting Schmitt trigger | NXP Semiconductors |
| 666953 | HEF40106BTT | HEF40106B; Hex inverting Schmitt trigger | Philips |
| 666954 | HEF40106BTT-Q100 | Hex inverting Schmitt trigger | Nexperia |
| 666955 | HEF40106BTT-Q100 | Hex inverting Schmitt trigger | NXP Semiconductors |
| 666956 | HEF4011B | Quadruple 2-input NAND gate | Philips |
| 666957 | HEF4011BD | Quadruple 2-input NAND gate | Philips |
| 666958 | HEF4011BDB | Quadruple 2-input NAND gate | Philips |
| 666959 | HEF4011BF | Quadruple 2-input NAND gate | Philips |
| 666960 | HEF4011BN | Quadruple 2-input NAND gate | Philips |
