Universum FT-81015, Service Manual

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n Output slope control to eliminate ground bounce
n 2 ms typical write cycle time, byte or page
n Up to eight devices may be connected to the same bus for up to 256K bits total memory
n Electrostatic discharge protection > 4000V
n Data retention > 200 years
n 8-pin PDIP and SOIC packages
n Temperature ranges
- Commercial (C): 0°C to +75°C
- Industrial (I): -40°C to +85°C
Pinning:
1. A0 User Configurable Chip Select
2. A1 User Configurable Chip Select
3. A2 User Configurable Chip Select
4. Vss Ground
5. SDA Serial Address/Data I/O
6. SCL Serial Clock
7. WPWrite P rotect Input
8. Vcc +2.5V to 6.0V Power Supply
DRAM
HYB514400BJ
The HYB514400BJ is the new generation dynamic RAM organised as 1M by 4-bit. It utilises CMOS silicon gate process as
well as advances circuit techniques to provide wide operation margins both internally and for the system user. This DRAM is
used with Megatext IC to store teletext pages.
Features:
n 1 048 576 words by 4-bit organisation
n 0 to 70 °C operating temperature
n Fast Page Mode Operation
n 5V (± 10 %) supply with a built-in VBB generator
n Low power dissipation
max. 660mW active (-50 version)
max. 605mW active (-60 version)
max. 550mW active (-70 version)
n Standby power dissipation
11mW max. Standby (TTL)
5.5mW max. Standby (CMOS)
1.1mW max. Standby (CMOS) for low Power Version
n Output unlatched at cycle and allows two-dimensional chip selection
n Read, writes, read-modify write, CAS-before-RAS refreshes,RAS-only refresh hidden refresh and test mode capability
n All inputs and outputs TTL-compatible
n 1024 refresh cycles / 16 ms
n 1024 refresh cycles / 128 ms Low Power Version only
n Plastic Packages: P-SOJ-26/20-5 with 300mil width
EPROM
ST27C2001
The ST27C2001 is 2097 152-bit, ultra-violet erasable, electrically programmable read-only memory. This device is fabricated
using power-saving CMOS technology for high speed and simple interface with MOS and bipolar circuits. All inputs (including
program data inputs) can be driven by series 74TTL circuits without the use of external pull-up resistors. Each output can
drive one series 74 TTL circuit without external resistors. Software for user interface and control of hardware circuitry are
stored in this IC.
Features:
n Organisation ...256K x 8
n Single 5-Vpover supply
n Operationally Compatible with Existing Megabit EPROMs
n Industry Standard 32-pinDual-in-line Package
n All inputs/Outputs Fully TTL Compatible
n Max Access/Min Cycle Time
n 8-Bit Output for Use in Microprocessor-Based Systems
n Power Saving CMOS Technology
n 3-State Output Buffers
n 400 mV Minimum DC Noise Immunity with Standard TTL Loads
n Latchup Immunity of 250mA on all input and output pins
n No pull-up resistors required
n Low power dissipation (Vcc = 5.5V)
- Active 165mW Worst case
- Standby 0.55mW Worst case (CMOS-Input levels)