GP521 Datasheet, PDF (1/8 Pages) Gennum Corporation – General Purpose Controller / Memory Chip for Hearing Instruments

General Purpose
Controller / Memory Chip
for Hearing Instruments
FEATURES
• general purpose
• EEPROM non-volatile memory
• 8 programmable current sink (PCS) control outputs
• can be configured with 6 PCS outputs for hearing
instruments (two switchable, four non-switchable)
• status register
• data transmission error detection
• synchronization of GP521 internal clocks with program
unit clock
STANDARD PACKAGING
• Chip (129 x 112 mils)
Au Bump
DESCRIPTION
The GP521 is a general purpose controller/memory chip in-
tended for use with audio signal path circuits in programmable
hearing instruments.
The GP521 uses a flexible communication standard which
allows room for future growth in programmable functions for
hearing instruments. The communication with the program unit
is over a bi-directional serial data link. Error detection circuitry
is used to avoid undesired changes in programmed settings.
GP521 - DATA SHEET
An information transfer dialogue consists of the address and
data for a register sent to the GP521 and the register contents
returned by the GP521. The function controlled by an output of
the GP521 is defined by the signal path circuit allowing current
controlled parameters. The relationship between the GP521
register addresses and the function on the signal path circuit
is defined by a data file in the programming unit. With this
format, any software developed for the GP521 can be used for
future generations of Gennum’s controller/memory circuits
and audio signal path circuits.
The GP521 uses EEPROM cells as the long term memory
element. These cells will retain the stored data when the power
supply is disconnected. Each EEPROM cell is combined with
a temporary (RAM) memory cell which makes it possible to
evaluate various control settings prior to saving them in the
long term EEPROM memory.
The GP521 controls the audio signal path circuit using eight
Programmable Current Sinks (PCS). Each PCS has 16 pro-
grammable settings. The circuit can be configured for either 6
or 8 PCS outputs. When used with a single pole single throw
switch (SPST) under the 6 PCS configuration , it is possible to
design a hearing instrument with two programmed settings
(i.e. adjusting a low cut filter for either noisy or quiet back-
ground environments). The 8 output configuration may be
used for circuits that require more programmable but non-
switchable settings. An external reference current is used for
the PCS’s so that the PCS outputs can track with the currents
in the audio signal path circuit.
BLOCK DIAGRAM
I_O1
10
I_O2
9
CONTROL OUTPUTS
CONTROL OUTPUTS
I_O3
I_O4
I_O5
I_O6
8
7
15
13
I_O7
12
I_O8
11
4 BIT
EEPROM
DAC
V
CC ₃
GND ⁵
4 BIT
EEPROM
DAC
4 BIT
EEPROM
DAC
4 BIT
EEPROM
DAC
4 BIT
EEPROM
DAC
4 BIT
EEPROM
DAC
4 BIT
EEPROM
DAC
4 BIT
EEPROM
DAC
REFERENCE
CURRENT
17 _{I RIR}
2
DATA
SERIAL TO PARELLEL
CONVERSION
DATA ERROR CHECKING
CONTROLLER TIMING
EEPROM
VOLTAGE
MULTIPLIER
STATUS &
OPERATION
REGISTER
1
CLOCK
Revision Date: May 1998
4
SW OFF
6
OS1
OSCILLATOR
16
N/C
14
N/C
Document No. 510 - 79 - 06
GENNUM CORPORATION P.O. Box 489, Stn. A, Burlington, Ontario, Canada L7R 3Y3 tel. [phone]
Web Site: www.gennum.com E-mail: [e-mail]