4464 / 41464 DRAM 64K x 4 pinout

DIP-18. Dynamic RAM, 64K x 4. Main RAM on the BBC Master; reported on later 130XE boards. UNVERIFIED

Four bits wide, 64K deep, +5 V only, with an output enable (/G) on pin 1. Same pinout as the 16K x 4 4416, plus A7 on pin 10. Eight address bits are multiplexed on A0-A7; refresh is all 256 rows every 4 ms. It is not a 4164 substitute (18 pins, 4 bits wide). Pin table from the TI TMS4464 data sheet. Atari: some later 130XE boards are reported to use 64K x 4 DRAMs, but Sams CC16 (1986) shows sixteen 64K x 1 DRAMs: U9-U16 main and U26-U33 extra RAM, with MT4264-15 and D4164-15 in its terminal guides and no 4464 anywhere. No Atari or Sams document read shows a 4464 130XE, so look at the board before ordering parts (verify).

Open the interactive 4464 pinout

Pins

Pin	Name	Type	Signal
1	/G	ctrl	Output enable. HIGH holds the data outputs in high impedance.
2	DQ1	data	Data in/out bit 1.
3	DQ2	data	Data in/out bit 2.
4	/W	ctrl	Write enable. LOW writes; HIGH reads.
5	/RAS	ctrl	Row address strobe. Latches the row address; a RAS-only cycle refreshes the row.
6	A6	addr	Multiplexed address bit 6.
7	A5	addr	Multiplexed address bit 5.
8	A4	addr	Multiplexed address bit 4.
9	VDD	power	+5 V, the only supply.
10	A7	addr	Multiplexed address bit 7.
11	A3	addr	Multiplexed address bit 3.
12	A2	addr	Multiplexed address bit 2.
13	A1	addr	Multiplexed address bit 1.
14	A0	addr	Multiplexed address bit 0.
15	DQ3	data	Data in/out bit 3.
16	/CAS	ctrl	Column address strobe. Latches the column address.
17	DQ4	data	Data in/out bit 4.
18	VSS	ground	0 V.

Fitted in

Atari 130XE
Commodore 64 U9, U10 (250466; U10, U11 on the 250469)
Apple IIe Two 64K x 4 RAMs on the enhanced CF ROM board (silk 64KX4 RAM, row F, columns 8 and 9); designators not read
ZX Spectrum +3 IC3-IC6 (64K x 4)
BBC Master 128 IC17, IC18, IC23, IC26

4464 / 41464 DRAM 64K x 4 pinout

Pins

Fitted in

Sources