March 1997
CDP1826C
CMOS 64-Word x 8-Bit
Static RAM
Features
• Ideal for Small, Low-Power RAM Memory Requirements in Microprocessor and Microcomputer Applications
• Interfaces with CDP1800-Series Microprocessors
Without Additional Address Decoding
• Daisy Chain Feature to Further Reduce External
Decoding Needs
• Multiple Chip-Select Inputs for Versatility
• Single Voltage Supply
• No Clock or Precharge Required.
Ordering Information
PKG.
PACKAGE TEMP. RANGE PART NUMBER
PDIP -40oC to +85oC CDP1826CE E22.4
NO.
Pinout
CDP1826C (PDIP)
TOP VIEW
V
BUS 0
BUS 1
BUS 2
BUS 3
BUS 4
BUS 5
BUS 6
BUS 7
CS1
CS2
V
SS
1
2
3
4
5
6
7
8
9
10
11
22
21
20
19
18
17
16
15
14
13
12
DD
A0
CS/A5
A1
A2
A3
A4
TPA
MRD
MWR
CEO
Description
The CDP1826C is a general purpose, fully static, 64-word x
8-bit random-access memory, for use in CDP1800-series or
other microprocessor systems where minimum component
count and/or price performance and simplicity in use are
desirable.
The CDP1826C has 8 common data input and data-output
terminals with three-state capability for direct connection to a
standard bidirectional data bus. Two chip-select inputs - CS1
and
CS2 - are provided to simplify memory-system expansion. An additional select pin, CS/A5, is provided to enable
the CDP1826C to be selected directly from the CDP1800
multiplexed address bus without additional latching or
decoding. In an 1800 system, the CS/A5 pin can be tied to
any MA address line from the CDP1800 processor. A TPA
input is provided to latch the high-order bit of this address
line as a chip-select for the CDP1826C. If this CS/A5 input is
latched high, and if CS = 1 and
time in the memory cycle, the CDP1826C will be enabled for
writing or reading. In a non-1800 system, the TPA pin can be
tied high, and the CS/A5 pin can be used as a normal
address input.
The six input-address buffers are gated with the chip-select
function to reduce standby current when the device is deselected, as well as to provide for a simplified power down
mode by reducing address buffer sensitivity to long fall times
from address drivers which are being powered down.
Two memor y control signals,
for reading from the writing to the CDP1826C. The logic is
designed so that
MWR overrides MRD, allowing the chip to
be controlled from a single R/
A CHIP ENABLE OUTPUT is provided for daisy-chaining to
additional memories or I/O devices. This output is high
whenever the chip-select function selects the CDP1826C,
which deselects any other chip which has its
nected to the CDP1826C CEO output. The connected chip is
selected when the CDP1826C is deselected and the
input is low. Thus, the CEO is only active for a read cycle
and can be setup so that a CEO of another device can feed
the
MRD of the CDP1826C, which in turn selects a third chip
in the daisy chain.
CS2 = 0 at the appropriate
MRD and MWR, are provided
W.
CS input con-
MRD
The CDP1826C has a recommended operating voltage of
4.5V to 5.5V and is supplied in 22 lead dual-in-line plastic
packages (E suffix). The CDP1826C is also available in chip
form (H suffix).
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
http://www.intersil.com or 407-727-9207
| Copyright © Intersil Corporation 1999
6-47
File Number 1311.2
ROM
ADDR BUS
TPA
RAM
CDP1826C
CDP1826C
CLEAR WAIT
ADDR BUS
TPA
CPU
CDP1800
SERIES
MRD
N0 - N2
TPB
Q
SCO SCI
INTERRUPT
I/O
DAT A
CONTROL
MRD
CEO
MRD
MWR
8-BIT BIDIRECTIONAL DATA BUS
DMA - IN DMA OUT
EF1 - EF4
FIGURE 1. TYPICAL CDP1802 MICROPROCESSOR SYSTEM
6-48
CDP1826C
Absolute Maximum Ratings Thermal Information
DC Supply Voltage Range, (VDD)
(All Voltages Referenced to VSS Terminal)
CDP1826C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.5V to +7V
Input Voltage Range, All Inputs . . . . . . . . . . . . .-0.5V to VDD +0.5V
DC Input Current, Any One Input. . . . . . . . . . . . . . . . . . . . . . . . .±10mA
Power Dissipation Per Package (PD)
TA = -40oC to +60oC (Package Type E) . . . . . . . . . . . . . . 500mW
TA = +60oC to +85oC (Package Type E). . . . . . Derate Linearly at
12mW/oC to 200mW
TA = -55oC to +100oC (Package Type D) . . . . . . . . . . . . . 500mW
TA = +100oC to +125oC (Package Type D). . . . Derate Linearly at
12mW/oC to 200mW
Thermal Resistance (Typical) θJA (oC/W) θJC (oC/W)
PDIP Package. . . . . . . . . . . . . . . . . . . 75 N/A
Device Dissipation Per Output Transistor
TA = Full Package Temperature Range
(All Package Types). . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100mW
Operating Temperature Range (TA)
Package Type D. . . . . . . . . . . . . . . . . . . . . . . . . .-55oC to +125oC
Package Type E. . . . . . . . . . . . . . . . . . . . . . . . . . .-40oC to +85oC
Storage Temperature Range (T
Lead Temperature (During Soldering)
At distance 1/16 ±1/32 In. (1.59 ±0.79mm)
from case for 10s max. . . . . . . . . . . . . . . . . . . . . . . . . . . . +265oC
). . . . . . . . . . . .-65oC to +150oC
STG
Recommended Operating Conditions At T
= Full Package Temperature Range. For maximum reliability, operating conditions
A
should be selected so that operation is always within the following ranges:
CDP1826C
PARAMETER SYMBOL
UNITSMIN MAX
DC Operating Voltage Range 4 6.5 V
Input Voltage Range V
Input Signal Rise or Fall Time, VDD = 5V tR, t
Static Electrical Specifications At T
= -40oC to +85oC, VDD = 5V ±5%, Except as Noted:
A
F
SS
-10µs
V
DD
CONDITIONS LIMITS
CDP1826C
PARAMETER SYMBOL
Quiescent Device Current I
Output Low (Sink) Current BUS I
CEO 0.4 0, V
Output High (Source) Current BUS I
CEO VDD -0.4 0, V
Output Voltage Low-Level V
Output Voltage High-Level V
Input Low Voltage V
Input High Voltage V
Input Leakage Current I
Operating Device Current (Note 2) I
OPER
Three-State Output Leakage Current I
Input Capacitance C
Output Capacitance C
DD
OL
OH
OL
OH
IL
IH
IN
OUT
IN
OUT
V
O
(V)
- 0, V
0.4 0, V
VDD -0.4 0, V
- 0, V
- 0, V
- - - - 1.5 V
- - 3.5 - - V
Any Input 0, V
- 0, V
0, V
DD
- - - 5 7.5 pF
- 0, V
V
0, V
(V)
IN
MIN
DD
DD
DD
DD
DD
DD
DD
DD
DD
DD
DD
1.6 3.2 - mA
0.8 1.6 - mA
-1.0 -1.5 - mA
-0.6 -1.0 - mA
VDD -0.1 V
(NOTE 1)
TYP MAX
-550µA
- 0 0.1 V
DD
-V
- ±0.1 ±1 µA
- 5 10 mA
- ±0.1 ±1 µA
-1015pF
NOTES:
1. Typical values are for TA = +25oC and nominal VDD.
2. Outputs open circuited; Cycle time = 1µs.
V
UNITS
6-49