HT1660
Pad Description
Pad No.
Pad Name
I/O
Description
1~33
SEG63~SEG95
SEG0~SEG62
O
LCD segment outputs
87~149
LCD common outputs, under 112´16 command mode, COM16~COM31 will
share to SEG96~SEG111. COM31/SEG96, COM30/SEG97, COM29/
SEG98....., COM18/SEG109, COM17/SEG110, COM16/SEG111
34~49
71~86
COM31~COM16
COM0~COM15
O
Chip selection input with pull-high resistor. When the CS is logic high, the
data and command read from or write to the HT1660 are disabled. The serial
interface circuit is also reset. But if the CS is at a logic low level and is input to
the CS pad, the data and command transmission between the host controller
and the HT1660 are all enabled.
50
CS
I
READ clock input with pull-high resistor. Data in the RAM of the HT1660 are
clocked out on the falling edge of the RD signal. The clocked out data will ap-
pear on the data line. The host controller can use the next rising edge to latch
the clocked out data.
51
52
RD
I
I
WRITE clock input with pull-high resistor. Data on the DATA line are latched
into the HT1660 on the rising edge of the WR signal.
WR
53~56
57
DB0~DB3
VSS
I/O Parallel data input/output with a pull-high resistor
Negative power supply for logic circuit, ground
¾
The OSCI and OSCO pads are connected to a 32.768kHz crystal in order to
generate a system clock. If the system clock comes from an external clock
source, the external clock source should be connected to the OSCI pad. But
if an on-chip RC oscillator is selected, the OSCI and OSCO pads can be left
open.
58
59
OSCI
I
OSCO
O
60
VDD
Positive power supply for logic circuit
¾
I
61
VLCD
IRQ
Power supply for LCD driver circuit
62
O
O
Time base or Watchdog Timer overflow flag, NMOS open drain output.
2kHz or 4kHz frequency output pair (tristate output buffer)
63, 64
BZ, BZ
Vary bias current pin
65~69
T1~T4, T000
I
It is usually not connected
Absolute Maximum Ratings
Supply Voltage...........................VSS-0.3V to VSS+5.5V
Input Voltage.............................VSS-0.3V to VDD+0.3V
Storage Temperature............................-50°C to 125°C
Operating Temperature...........................-25°C to 75°C
Note: These are stress ratings only. Stresses exceeding the range specified under ²Absolute Maximum Ratings² 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 reliabil-
ity.
Rev. 1.30
5
April 13, 2006
HOLTEK [ HOLTEK SEMICONDUCTOR INC ]
