HT16525
5x8 Dot Character VFD
Controller & Driver
Feature
• Logic voltage : 2.7V~5.5V
• High voltage: 60V (max.)
• 3-line serial interface
• Alphanumeric and symbolic display using
integrated ROM
• 24 x 8-bit display data RAM (DDRAM)
• Integrated 5x8 dot ROM containing 248 character
set
• 8 user-defined characters stored in character data
RAM (CGRAM)
• Additional symbol display data stored in 24 x 8-bit
RAM (ADRAM)
• Display content:
24 columns by 1 row + 48 symbols - each column
has 1 digit character with 2 symbols
• Supports display output: 40-segment & 24-grid
• Supports symbol output: 2-symbol & 24-grid
• Supports 2-pin general output port - static operation
• Fully integrated oscillator circuit
• 80-pin LQFP package
Applications
• Consumer products panel function control
• Industrial measuring instrument panel function
control
• Other similar application panel function control
• Suitable for POS terminals or message displays
General Description
The HT16525 device is a dot matrix Vacuum
Fluorescent Display, VFD, controller/driver which
displays characters, numerics and symbols. Dot
matrix VFD driving signals are received via a 3-line
serial interface driven by an externally connected
microcontroller. The display data is stored in the
internal ROM and RAM for character and symbol
display.
Ordering Information
Part Number
HT16525-001
HT16525-002
Information
80-pin LQFP package with ROM code 001
80-pin LQFP package with ROM code 002
Rev. 1.00
1
January 18, 2012
HT16525
Block Diagram
VDD
VH
VSS
TEST
RST
DDRAM
24w x 8b
CGROM
248w x 40b
CGRAM
8w x 40b
ADRAM
24w x 2b
CS
SCK
SI
8 bit shift
register
S1
Segment
Driver
S40
AD1
AD
Driver
AD2
Address
Selector
Command
decoder
Write
address
counter
Read
address
counter
Control
Circuit
Port
Driver
P1
P2
G1
Digit
control
Duty
control
Timing
generator1
Timing
generator2
Grid
Driver
G24
OSCI
Oscillator
Rev. 1.00
2
January 18, 2012
HT16525
Pin Assignment
G21
G22
G23
G24
VH
VSS
OSCI
TEST
RST
CS
SCK
SI
VDD
P1
P2
AD2
AD1
S1
S2
S3
S4
S5
S6
S7
S8
S9
S10
S11
S12
S13
S14
S15
S16
S17
S18
S19
S20
S21
S22
S23
80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 64 63 62 61
1
60
2
59
3
58
4
57
5
56
6
55
7
54
8
53
9
52
HT16525
10
51
11
40
80 LQFP-A
12
49
13
48
47
14
46
15
45
16
44
17
43
18
42
19
20
41
21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 3738 39 40
G20
G19
G18
G17
G16
G15
G14
G13
G12
G11
G10
G9
G8
G7
G6
G5
G4
G3
G2
G1
Pin Description
Pin Name
Power Supply Pins
VDD
VH
VSS
—
—
—
Positive power supply for logic circuits
Power supply for VFD driver circuits
VSS - ground pin
Chip select pin
When “Low”, the device is active.
Serial clock input
Shift clock input with data written on the SCK rising edge.
Serial data input.
The serial data is first shifted from LSB.
Initialize all the internal registers and commands.
All segments and digits are fixed at “Low” level.
When “Low” or open, the device is in normal mode.
When “High”, the device is in test mode.
High-voltage segment output pins.
High-voltage grid output pins.
High-voltage additional data segment output pins.
General port output.
Static operation output - can drive LEDs
Oscillator input pin
Connected to an external resistor and capacitor to generate the oscillation
frequency.
I/O
Description
Microcontroller Interface Pins
CS
SCK
SI
RST
TEST
Output Pins
S1~S40
G1~G24
AD1, AD2
P1, P2
Oscillator Pin
OSCI
I
O
O
O
O
I
I
I
I
I
Rev. 1.00
NC
S24
S25
S26
S27
S28
S29
S30
S31
S32
S33
S34
S35
S36
S37
S38
S39
S40
NC
NC
3
January 18, 2012
HT16525
Approximate Internal Connections
CS, SCK, SI, RST
(For Schmit Trigger Type)
VDD
S1~S40, G1~G24, AD1, AD2
P1, P2
VH
VDD
VSS
VSS
VSS
TEST
VDD
VSS
Absolute Maximum Ratings
Logic Supply Voltage ............... Vss-0.3V to Vss+6.0V
Driver Supply Voltage .............. Vss-0.3V to Vss+66V
.
Input Voltage ..
………………
Vss-0.3V to V
DD
+0.3V
.
Output Voltage .........................Vss-0.3V to V
DD
+0.3V
Grid output current .............................. -20mA to 4mA
.
Segment output current ........................ -10mA to 4mA
AD output current ................................ -15mA to 4mA
General port output current ................ -20mA to 40mA
Storage Temperature ........................... -55°C to 125°C
Operation Temperature ......................... -40°C to 85°C
Note: These are stress ratings only. Stresses exceeding the range specified under “Absolute Maximum Ratings”
may cause substantial damage to the device. Functional operation of this device at other conditions beyond
those listed in the specification is not implied and prolonged exposure to extreme conditions may affect
device reliability.
Rev. 1.00
4
January 18, 2012
HT16525
D.C. Characteristics
Symbol
V
DD
V
H
I
DD1
Parameter
Logic Supply Voltage
VFD Supply Voltage
VDD Operating Current
Test Condition
V
DD
—
—
5V
3V
5V
I
DD2
VDD Operating Current
3V
5V
3V
—
Condition
—
—
f
OSC
=2MHz, no load, Duty=15/16,
Digit=1 to 24, All output lights
ON, MCU no write data or
command, P2 and P1=high
f
OSC
=2MHz, no load, Duty=15/16,
Digit=1 to 24, Stop scan, MCU
no write data or command, P2
and P1=high
Standby mode
f
OSC
=2MHz, no load, Duty=15/16,
Digit=1 to 24, All output lights
ON, MCU no write data or
command, P2 and P1=high
f
OSC
=2MHz, no load, Duty=15/16,
Digit=1 to 24, Stop scan, MCU
no write data or command, P2
and P1=high
Standby mode
CS, SCK, SI, RST
CS, SCK, SI, RST
V
IH
=V
DD
, CS, SCK, SI, RST
V
IL
=0V, CS, SCK, SI, RST
G1~G24, I
OH1
=-15mA
AD1, AD2, I
OH2
=-7mA
S1~S40, I
OH3
=-1mA
P1, P2
G1~G24, I
OL1
=1mA
AD1, AD2, I
OL2
=1mA
S1~S40, I
OL3
=1mA
P1, P2
TEST Pin
I
OL4
=20mA
I
OL4
=10mA
I
OH4
=-2mA
I
OH4
=-1mA
V
H
=50V, V
SS
=0V, Ta=-40°C ~ 85°C
Min.
2.7
20
—
—
—
—
—
—
—
Typ.
5.0
—
—
—
—
—
2
2
—
Max.
5.5
60
2
1
2
1
—
—
1
mA
mA
Unit
V
V
I
STB
VDD Standby Current
μA
I
H1
VH Operating Current
mA
I
H2
I
H_STB
V
IH
V
IL
I
IH
I
IL
V
OH1
V
OH2
VH Operating Current
VH Standby Current
High Level Input Voltage
Low Level Input Voltage
High Level Input Current
Low Level Input Current
—
—
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
—
—
0.8V
DD
—
—
-1
45
46
46
0.9V
DD
0.9V
DD
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
50
100
20
20
—
0.2V
DD
1
—
—
—
—
—
—
5
5
5
1
1
100
200
μA
μA
V
V
μA
μA
V
V
V
V
V
V
V
V
kW
kW
High Level Output Voltage
V
OH3
V
OH4
V
OL1
V
OL2
Low Level Output Voltage
V
OL3
V
OL4
R
PD
Pull Down Resistor
Rev. 1.00
5
January 18, 2012
