Page 1 of 10
IA16450 Preliminary Data Sheet
Universal Asynchronous Receiver/Transmitter
Copyright 1999, InnovASIC Inc.
Customer Specific IC Solutions
FEATURES
• Form, Fit, and Function Compatible with the National NS16450
• Packaging options available: 40 Pin Plastic or 44 Pin Plastic Leaded Chip
Carrier
• Programmable Word Length, Stop Bits, and Parity
• Full Duplex Operation
• Programmable Baud Rate Generator
- Division of any input clock by 1 to (216 –1)
- Generates Internal 16 x clock
• Programmable Serial-Interface
- 5-, 6-, 7- or 8-bit characters
- Even, Odd, or No-Parity Bit Generation and Detection
- 1-, 1 ½-, or 2-Stop Bit Generation
- Baud Generation of DC to 56k
• Prioritized Interrupt Control
• Internal Diagnostic/Loopback Capabilities
The IA16450 uses innovASIC’s innovative new f 3 Program to provide industry with parts that
other vendors have declared obsolete. By specifying parts through this program a customer is
assured of never having a component become obsolete again. This advanced information sheet
assumes the original part has been designed in, and so provides a summary of capabilities only. For
new designs contact innovASIC for more detailed information.
National is a copyright trademark of National Semiconductor Corporation
Package Pinout
44 Pin LCC
IA16450
(12)N. C.
(7)D5
(8)D6
(9)D7
(10)RCLK
(11)SIN
(13)SOUT
(14)CS0
(15)CS1
(16)CS2_n
(17)BAUDOUT_n
MR
INTR
N. C.
OUT2_n
DTR_n
OUT1_n
WR_n
XIN
XOUT
(6)
(5)
(4)
(3)
(2)
(1)
(44)
(43)
(42) DCD_n
(41) DSR_n
(40) CTS_n
D3
D4
(34)
(39)
(38)
(37)
(36)
(35)
(33)
(32)
(31)
(30)
(29)
(18)
(19)
(20)
(21)
(22)
(23)
(24)
(25)
(26)
(27)
(28)
VCC
RI_n
D0
N. C.
D2
D1
VSS
WR
RD_n
N. C.
DDIS
RD
ADS_n
CSOUT
A2
A1
A0
N. C.
RTS_n
(6)
(1)
(2)
(3)
(4)
(5)
(7)
(8)
(9)RCLK
(10)SIN
(11)SOUT
(12)CS0
(13)CS1
(14)
40 Pin DIP
IA16450
RTS_n
OUT2_n
INTR
N. C.
(20)VSS
(15)BAUDOUT_n
(16)XIN
(17)XOUT
(18)WR_n
(19)WR (21)
(22)
(23)
(24)
RD
RD_n
(40)
(39)
(38)
(37)
(36)
(35)
(34)
(33)
(32)
(31)
(30)
(29)
(28)
(27)
(26)
(25)
CS2_n
CSOUT
DDIS
A2
ADS_n
A0
A1
OUT1_n
DTR_n
CTS_n
MR
DCD_n
DSR_n
VCC
RI_n
D5
D0
D1
D2
D3
D4
D6
D7
Page 2 of 10
IA16450 Preliminary Data Sheet
Universal Asynchronous Receiver/Transmitter
Copyright 1999, InnovASIC Inc.
Customer Specific IC Solutions
The IA16450 is a form, fit and function compatible part to the National NS16450 Univeral
Asynchronous Receiver/Transmitter. The IA16450 function receives and transmits data in a variety
of configurations including 5, 6, 7 or 8 bit data words, odd, even or no parity, and 1, 1.5, and 2 stop
bits. This megafunction includes an internal Baud Rate Generator and Interrupt Control. A block
diagram is shown in Figure 1.
Functional Block Diagram
Figure 1
DATA BUS
BUFFER
RECEIVER
BUFFER
REGISTER
LINE CONTROL
REGISTER
DIVISOR LATCH
(LSB)
DIVISOR LATCH
(MSB)
LINE STATUS
REGISTER
TRANSMITTER
HOLDING
REGISTER
MODEM
CONTROL
REGISTER
MODEM STATUS
REGISTER
INTERRUPT
ENABLE
REGISTER
INTERRUPT ID
REGISTER
INTERNAL DATA
BUS
RECEIVER
SHIFT
REGISTER
RECEIVER
TIMING
&
CONTROL
TRANSMITTER
TIMING
&
CONTROL
TRANSMITTER
SHIFT
REGISTER
INTERRUPT
CONTROL
LOGIC
MODEM
CONTROL
LOGIC
BAUD
GENERATOR
SIN
RCLK
BAUDOUT_n
SOUT
RTS_n
CTS_n
DTR_n
DSR_n
DCD_n
RI
OUT1_n
OUT2_n
INTR
DECODE
AND
CONTROL
LOGIC
A0
A1
A2
CS0
CS1
CS2_n
ADS_n
MR
RD
RD_n
WR
WR_n
DDIS
CSOUT
XIN
XOUT
D7:D0
Page 3 of 10
IA16450 Preliminary Data Sheet
Universal Asynchronous Receiver/Transmitter
Copyright 1999, InnovASIC Inc.
Customer Specific IC Solutions
I/O Signal Description
Table 1 below describes the I/O characteristics for each signal on the IC. The signal names
correspond to the signal names on the pinout diagrams provided. Table 2 refers to the address
register map. Table 3 refers to the Preliminary A. C. Characteristics. Figure 2 illustrates the
Preliminary Timing Waveforms for this device. Environmental/Qualification Levels are listed in
Table 4.
Table 1
Name Type Description
MR IMaster Reset - Active high - Clears all registers (except the
receiver buffer, transmitter holding and divisor latches) to their
initial state. Resets internal control logic to its initial state
A(2:0) IRegister Address - Active high - This bus selects one of the
internal UART registers (refer to table 1). Note the state of the
divisor latch access bit (DLAB - the msb of the line control
register) must be set high to access the divisor latches and low
to access the receiver buffer or the interrupt enable register.
DIN(7:0) IData Input Bus - Active high - Serves as input data when
writing to internal UART registers.
CS0 IChip Select 0 - Active high - When CS0, CS1 and CS2 are active
the megafunction is selected. Read and write transactions to
internal UART registers are then possible.
CS1 IChip Select 1 - Active high - When CS0, CS1 and CS2 are active
the megafunction is selected. Read and write transactions to
internal UART registers are then possible.
CS2_n IChip Select 2 - Active low - When CS0, CS1 and CS2 are active
the megafunction is selected. Read and write transactions to
internal UART registers are then possible.
ADS_n IAddress Strobe - Active low - Gating signal to the Address
input latch. The positive edge of ADS_n latches the state of the
register address bus into the Address input latch. If address
signals are guaranteed to be stable for the duration of a read or
write cycle, ADS_n may be tied low thus forcing the Address
input latch to be transparent.
RD IRead Control - Active High - when RD is high or RD_n is low
and the UART is selected, read transactions from internal
UART registers are possible.
Page 4 of 10
IA16450 Preliminary Data Sheet
Universal Asynchronous Receiver/Transmitter
Copyright 1999, InnovASIC Inc.
Customer Specific IC Solutions
Name Type Description
RD_n IRead Control - Active low - when RD is high or RD_n is low
and the UART is selected, read transactions from internal
UART registers are possible.
WR IWrite Control - Active High - when WR is high or WR_n is low
and the UART is selected, write transactions to internal UART
registers are possible.
WR_n IWrite Control - Active low - when WR is high or WR_n is low
and the UART is selected, write transactions to internal UART
registers are possible.
SIN ISerial Data Input - Active High - Receive data to the UART
RCLK IReceive Clock - The 16x baud rate clock used by the receiver
section of the UART.
CTS_n IClear To Send - Active Low - Active state indicates that the
MODEM or data set is ready to exchange data. A change in
state of this input is recorded in the DCTS bit (bit 0) of the
MODEM Status register. Whenever CTS_n changes state, an
interrupt is generated if the MODEM Status interrupt is
enabled. The complement of this input is recorded in the CTS
(bit 4) bit of the MODEM Status register
DSR_n IData Set Ready - Active Low - Active state indicates that the
MODEM or data set is ready to establish the communications
link with the UART. A change in state of this input is recorded
in the DDSR bit (bit 1) of the MODEM Status register.
Whenever DSR_n changes state, an interrupt is generated if the
MODEM Status interrupt is enabled. The complement of this
input is recorded in the DSR (bit 5) bit of the MODEM Status
register
DCD_n IData Carrier Detect - Active Low - Active state indicates that
the data carrier has been detected by the MODEM or data set.
A change in state of this input is recorded in the DDCD bit (bit
3) of the MODEM Status register. Whenever DCD_n changes
state, an interrupt is generated if the MODEM Status interrupt
is enabled. The complement of this input is recorded in the
DCD (bit 7) bit of the MODEM Status register
Page 5 of 10
IA16450 Preliminary Data Sheet
Universal Asynchronous Receiver/Transmitter
Copyright 1999, InnovASIC Inc.
Customer Specific IC Solutions
Name Type Description
RI_n IRing Indicator - Active Low - Active state indicates that the ring
signal has been detected by the MODEM or data set. A change
in state of this input is recorded in the TERI bit (bit 2) of the
MODEM Status register. Whenever DSR_n changes state, an
interrupt is generated if the MODEM Status interrupt is
enabled. The complement of this input is recorded in the RI
(bit 6) bit of the MODEM Status register
DOUT(7:0) OData Output Bus - Active high - Serves as output data when
reading from internal UART registers.
DDIS ODriver Disable - Active High - Active State indicates that the
CPU is reading data from the UART. This output is intended as
a disable or direction control between the UART and CPU.
CSOUT OChip Select Output - Active High - Active State indicates that
the megafunction has been selected by use of the CS0, CS1 and
CS2_n inputs.
SOUT OSerial Data Out - Active High - Serial (transmit) data out. This
signal is set to the marking (logic 1) state upon master reset.
BAUDOUT_n OBaud Out - Active Low - The 16x baud rate clock used by the
transmitter section of the UART. This output is controlled by
the programmable baud rate generator.
RTS_n ORequest to Send - Active Low - This output indicates that the
UART is ready to exchange data. This output is controlled by
writing to the RTS (bit 1) bit of the control register.
DTR_n OData Terminal Ready - Active Low - This output indicates that
the UART is ready to establish a communications link. This
output is controlled by writing to the DTR (bit 0) bit of the
control register.
OUT1_n ODiscrete Output - Active Low - One of two user-programmable
discrete outputs. This output is controlled by writing to the
OUT1 (bit 2) bit of the control register.
OUT2_n ODiscrete Output - Active Low - One of two user-programmable
discrete outputs. This output is controlled by writing to the
OUT2 (bit 3) bit of the control register.
INTR OInterrupt - Active High - Indicates that an enabled interrupt has
had its interrupt condition met.
Page 6 of 10
IA16450 Preliminary Data Sheet
Universal Asynchronous Receiver/Transmitter
Copyright 1999, InnovASIC Inc.
Customer Specific IC Solutions
Name Type Description
XIN IExternal Crystal Input. This signal iniput is used in conjuction
with XOUT to form a feedback circuit for the baud rate
generator’s oscillator. If a clock signal will be generated off-
chip, then it should drive the baud rate generator through this
pin
XOUT OExternal Crystal Output. This signal output is used in
conjuction with XIN to form a feedback circuit for the baud
rate generator’s oscillator. If the clock signal will be generated
off-chip, then this pin is unused.
VSS PGround.
VCC P+5V power.
IA16450 Register Address Map
Table 2
DLAB A2 A1 A0 REGISTER DESCRIPTION
0 0 0 0 Receiver Buffer - Read Only
Transmitter Holding Register - Write Only
1 0 0 0 Divisor Latch (LSB)
0 0 0 1 Interrupt Enable Register
1 0 0 1 Divisor Latch (MSB)
X010Interrupt ID Register
X011Line Control Register
X100MODEM Control Register
DATA
X101Line Status Register
X110MODEM Status Register
X111Scratch
Page 7 of 10
IA16450 Preliminary Data Sheet
Universal Asynchronous Receiver/Transmitter
Copyright 1999, InnovASIC Inc.
Customer Specific IC Solutions
AC Electrical Characteristics
Table 3
Symbol Min Max
tADS 25
tAH 0
tAR 20
tAS 25
tAW 20
tCH 0
tCS 25
tCSC 33
tCSR 20
tCSW 20
tDH 10
tDS 20
tHZ 0 25
tRA 0
tRC 36
tRCS 0
tRD 60
tRDD 20
tRVD 31
tWA 0
tWC 36
tWCS 0
tWR 60
RC 115
WC 115
Parameter
Address Strobe Width
Address Hold Time
RD, RD_n Delay from Address (Note 1)
Address Setup Time
WR, WR_n Delay from Address (Note 1)
Chip Select Hold Time
Chip Select Setup Time
Chip Select Output Delay from Select (Note 1)
RD, RD_n Delay fron Select (Note 1)
WR, WR_n Delay fron Select (Note 1)
Data Hold Time
Data Setup Time
RD, RD_n to Floating Data Delay
Address Hold Time from RD, RD_n (Note 1)
Read Cycle Delay
Chip Select Hold Time from RD, RD_n (Note 1)
RD, RD_n Strobe Width
RD, RD_n to Driver Disable Delay
Delay from RD, RD_n to Data
Address Hold Time from WR, WR_n
Write Cycle Delay
Chip Select Hold Time from WR, WR_n (Note 1)
WR, WR_n Strobe Width
Read Cycle = tAR + tRD
+ tRC
Write Cycle = tAW + tWR
+tWC
Note 1: Applicable only when ADS_n is tied low.
Page 8 of 10
IA16450 Preliminary Data Sheet
Universal Asynchronous Receiver/Transmitter
Copyright 1999, InnovASIC Inc.
Customer Specific IC Solutions
Timing Waveforms
Figure 2
ADS_n
A2,A1,A0
CS2_n,CS1,CS0
CSOUT
WR_n,WR
RD_n,RD
DATA,D0:D7
ADS_N
A2,A1,A0
CS2_n,CS1,CS0
CSOUT
RD_n,RD
WR_n,WR
DDIS
DATA,D0:D7
VALID
VALID
ACTIVE ACTIVE
ACTIVE
VALID DATAVALID DATA
VALID
VALID
ACTIVE ACTIVE
ACTIVE
VALID DATAVALID DATA
tCSC
tRA
tRCS
WC
tWR
tDS tDH
tADS
tAS
tCS
tWC
tCSW
tAW
tCSC
tWA
tWCS
RC
tRD
tADS
tAS
tCS
tRC
tCSR
tAR
tRDD tRDD
tRVD tHZ
tAH
tCH
tAH
tCH
Write Cycle
Read Cycle
Page 9 of 10
IA16450 Preliminary Data Sheet
Universal Asynchronous Receiver/Transmitter
Copyright 1999, InnovASIC Inc.
Customer Specific IC Solutions
Qualification Levels
Table 4
Part Number Environmental/ Qual Level
IA16450-PDW40C Commercial
IA16450-PLC44C Commercial
IA16450-PDW40I Industrial
IA16450-PLC44I Industrial
The following diagram depicts the innovASIC Product Identification Number.
IAXXXXX-PPPPNNNT/SP
Special Processing:
S = Space
Q = MIL-STD-883
Temperature:
C = Commercial
I = Industrial
M = Military
Number of Leads
Package Type:
Per Package Designator Table
IC Base Number
innovASIC Designator
Page 10 of 10
IA16450 Preliminary Data Sheet
Universal Asynchronous Receiver/Transmitter
Copyright 1999, InnovASIC Inc.
Customer Specific IC Solutions
Package Designator Table
Package Type innovASIC
Designator
Ceramic side brazed Dual In-line CDB
Cerdip with window CDW
Ceramic leaded chip carrier CLC
Cerdip without window CD
Ceramic leadless chip carrier CLL
PLCC PLC
Plastic DIP standard (300 mil) PD
Plastic DIP standard (600 mil) PDW
Plastic metric quad flat pack PQF
Plastic thin quad flat pack PTQ
Skinny Cerdip CDS
Small outline plastic gull-wing(150 mil body) PSO
Small outline medium plastic gull-wing (207 mil body) PSM
Small outline narrow plastic gull wing (150 mil body) PSN
Small outline wide plastic gull wing (300 mil body) PSW
Skinny Plastic Dip PDS
Shrink small outline plastic (5.3mm .208 body) PS
Thin shrink small outline plastic PTS
Small outline large plastic gull wing (330 mil body) PSL
Thin small outline plastic gull-wing (8 x 20mm) [TSOP] PST
PGA CPGA
BGA CBGA
Contact innovASIC for other package and processing options.
