April 1998
1/3
This is preliminary information on a new product in development or undergoing evaluation. Details are subject to change without notice.
R
ST7275-1
8-BIT, 56-PIN MCU FOR MONITORS, WITH UP TO 60K ROM, 2K
RAM, ADC, TIMER, IR, SYNC, PWM/BRM, DDC/DMA, I
2
C & SCI
PRODUCT PREVIEW
s
User ROM/OTP/EPROM: up to 60 Kbytes
s
Data RAM: up to 2 Kbytes (256 bytes stack)
s
8 MHz Maximum Internal Clock Frequency in
fast mode, 4 MHz in normal mode
s
Run, Wait and Halt CPU modes
s
Sync Processor for Mode Recognition, power
management and composite video blanking,
clamping and free-running frequency
generation.
Corrector mode
Analyzer mode
s
Fast I
2
C Multi Master Interface
s
DDC Bus Interface fully compliant with DDC1,
2B, 2B+, 2AB, 2Bi standards
s
32 I/O lines
8 Open Drain I/Os with high current capacity
(10 mA) on port A
5 lines programmable as interrupt inputs
s
16-bit timer with 2 input captures and 2 output
compare functions (with 1 output pin)
s
8-bit Analog to Digital Converter with 8
channels on port B
s
8 10-bit PWM/BRM Digital to Analog outputs
s
One 12-bit PWM/BRM Digital to Analog output
s
Asynchronous Serial Communications
Interface
s
Infra red controller
s
Master Reset and Power on/off reset
1
s
Programmable Watchdog for system reliability
s
56-pin Shrink Dual In line Plastic package
s
Fully static operation
s
0 to + 70
o
C operating temperature range
s
4.0V to 5.5V supply operating range
s
24 MHz Quartz Oscillator
s
63 basic instructions/17 main address modes
s
8x8 unsigned multiply instruction
s
True bit manipulation
s
Versatile Development Tools (DOS and
Windows) including assembler, linker, C-
compiler, archiver, source level debugger,
EPROM programmer and hardware emulator
Device Summary
Note 1: Power On/Off reset not implemented in
this revision.
Features
ST72751N9
ST72751N7
ST72751N6
ROM
(bytes)
60K 48K 32K
RAM
(bytes)
2K
1.5
1
ADC
8 channels
Timer
1
I
2
C Bus
one multimaster
DDC/DMA
yes
Sync yes
PWM
9
I/O
32
SCI
yes
IR
yes
EPROM
Device
ST72E751N9D1
OTP
Device
ST72T751N9B1
PSDIP56
See Ordering Information at the end of the Document
1
2/3
ST7275-1
1 GENERAL DESCRIPTION
1.1 INTRODUCTION
The ST7275 is a HCMOS microcontroller unit
(MCU) from the ST7 family with dedicated periph-
erals for Monitor applications.
It is based around an industry standard 8-bit core
and offers an enhanced instruction set. The proc-
essor runs with an external clock at 24 MHz with
a 5V supply. Due to the fully static design of this
device, operation down to DC is possible. Under
software control the ST7275 can be placed in
WAIT or HALT mode thus reducing power con-
sumption. The enhanced instruction set and ad-
dressing modes afford real programming potential.
In addition to standard 8-bit data management the
ST7 features true bit manipulation, 8x8 unsigned
multiplication and indirect addressing modes.
The device includes an on-chip oscillator, CPU,
Sync Processor for video timing & Vfback analy-
sis, up to 60K ROM, up to 2K RAM, I/O, a timer
with 2 input captures and 2 output compares, an 8-
channel Analog to Digital Converter, DDC/DMA,
I
2
C multi Master, SCI Serial Communications In-
terface, Watchdog Reset, an Infra Red Control
preprocessor, and one 12-bit and eight 10-bit
PWM/BRM outputs for analog DC control of exter-
nal functions.
Figure 1. ST7275-1 Block Diagram
SYNC
PROCESSOR
POWER
SU PPLY
OSC /3 or 6
V
DD
POR T A
PORT C
P
C
L
A
D
D
R
E
S
S
/
D
A
T
A
B
U
S
E
S
DDC
TIM ER
WATCHDOG
PORT D
C
S
Y
N
C
I
H
S
Y
N
C
O
V
S
Y
N
C
O
H
/
C
S
Y
N
C
V
S
Y
N
C
OCMP
C
L
A
M
P
O
U
T
PWM/BRM
PORT B
ADC
A IN 0-A IN7
DA0
60K Bytes
RAM
2K Bytes
CONTROL
8-BIT CORE
ALU
P
C
H
S
P
X
Y
A
C
C
INTERNAL
CLOC K
V
SS
OSCOUT
OSCIN
DA1,DA8
H
S
Y
N
C
I
2
V
S
Y
N
C
I
2
DDC DM A
H
F
B
A
C
K
PORT C
SCLD
SDAD
IC
INFRA RED
S
C
L
I
S
D
A
I
SC I
(UART)
VR01735Q
PA0..6
PA7/BLANKOUT
V
D D A
V
S S A
PC3/SDAD
PC2/RX/SCLD
PC0/OCMP/HFBACK
RESET
HSYNCI1
VSYNCI1
PB1..7/ AIN1..7
VFBACK/AIN0
PC1/HSYNCI2
PC4/SCLI
PC5/SDAI
PC6/RDI
PC7/TDO
IRIN
POWER ON/OFF
TDO
RDI
ROM/
Up to
Up to
PB0/
PD0/CSYNCI
PD1/HSYNCO
PD2/VSYNCO
PD3/ITC
PD4/ITB
PD5/ITA
PD6/CLAMPOUT
PD7/VSYNCI2/ITD
OTP/EPROM
V
F
B
A
C
K
Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no
responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third
parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights
of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without notice.
This publication supersedes and replaces all information previously supplied. SGS-THOMSON Microelectronics products
are not authorized for use as critical components in life support devices or systems without the express written approval
of SGS-THOMSON Microelectronics.
1998 SGS-THOMSON Microelectronics - All Rights Reserved.
Purchase of I
2
C Components by SGS-THOMSON Microelectronics conveys a license under the Philips I
2
C Patent. Rights to use these
components in an I
2
C system is granted provided that the system conforms to the I
2
C Standard Specification as defined by Philips.
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