King Billion Electronics Co., Ltd.
HE89C21
駿 億 電 子 股 份 有 限 公 司
HE80000 SERIES
Pin Name
Pin # I/O
Description
LCD Charge Pump Voltage V1
LCD Charge Pump Voltage V2
LCD Charge Pump Voltage V3
Power ground Input.
LV1
45
B
B
B
P
LV2
LV3
GND
46
47
48
System Reset input pin. Level trigger, active low on this pin will put the chip in reset
state.
RSTP_N
49
I
External fast clock pin. Two types of oscillator can be selected by MO_FXTAL (‘0’
FXO,
FXI
O, for RC type and ‘1’ for crystal type). For RC type oscillator, one resistor need to be
50, 51
B
connected between FXI and GND. For crystal oscillator, one crystal need to be
placed between FXI and FXO. Please refer to application for details.
Test input pin. Please bond this pad and reserve a test point on PCB for debugging.
But for improving ESD, please connect this point with zero Ohm resistor to GND.
External slow clock pins. Slow clock is clock source for LCD display, TIMER1,
Time-Base, DTMF generator and other internal blocks. 32768 Hz crystal or resonator
should be used for DTMF generator to function properly.
TSTP_P
52
I
SXO,
SXI
O,
I
53, 54
Positive power Input. 0.1 µF decoupling capacitors should be placed as close to IC
VDD and GND pads as possible for best decoupling effect.
MUTE is open drain type output for muting microphone of telephone speech
network.
VDD
55
56
57
P
MUTE
DTMFO
O
O
Dual-Tone Multiple Frequency Tone Output for dialing purpose. It can also be used
as two-channel general purpose tone generator with frequency resolution of 1 Hz.
8-bit bi-directional general purpose I/O port D. The output type of I/O pad can also
be selected by mask option MO_DPP[7..0] (‘1’ for push-pull and ‘0’ for open-drain).
As the output structure of I/O pad does not contain tri-state buffer. When using the
I/O as input, ‘1’ must be outputted before reading the pin.
PRTD[7..0] 58 ~ 65
B
The initial state of PRTD[2..0] can be determined by mask option MO_IH[2..0],
while initial state of PRTD[7..3] is always ‘1’.
PRTD[7..2] can be used as wake-up pins. PRTD[7..6] can be used as external
interrupt sources.
January 20, 2003
3
V1.0E
KB [ King blillion Electronics Co.,Ltd. ]
