H49R50A-1 Datasheet, PDF (21/45 Pages) Holtek Semiconductor Inc – LCD Type 8-Bit MCU

HT49R50A-1/HT49C50-1/HT49C50L
LCD Driver Output
The output number of the LCD driver device can be
32´2, 33´3 or 32´4 by option (i.e., 1/2 duty, 1/3 duty or
1/4 duty). The bias type LCD driver can be ²R² type or
²C² type for HT49R50A-1/HT49C50-1 while the bias
type LCD driver can only be ²C² type for HT49C50L. If
the ²R² bias type is selected, no external capacitor is re-
quired. If the ²C² bias type is selected, a capacitor
mounted between C1 and C2 pins is needed. The LCD
driver bias voltage for HT49R50A-1/HT49C50-1 can be
1/2 bias or 1/3 bias by option, while the LCD driver bias
voltage for HT49C50L can only be 1/2 bias. If 1/2 bias is
selected, a capacitor mounted between V2 pin and
ground is required. If 1/3 bias is selected, two capacitors
are needed for V1 and V2 pins.
LCD bias power supply selection for HT49R50A-1/
HT49C50-1: There are two types of selections: 1/2 bias
or 1/3 bias.
LCD bias type selection for HT49R50A-1/HT49C50-1:
This option is to determine what kind of bias is selected,
R type or C type.
Low Voltage Reset/Detector Functions
There is a low voltage detector (LVD) and a low voltage
reset circuit (LVR) implemented in the microcontroller.
These two functions can be enabled/disabled by op-
tions. Once the options of LVD is enabled, the user can
use the RTCC.3 to enable/disable (1/0) the LVD circuit
and read the LVD detector status (0/1) from RTCC.5;
otherwise, the LVD function is disabled.
The LVR has the same effect or function with the exter-
nal RES signal which performs chip reset. During HALT
state, LVR is disabled.
Rev. 2.00
D u r in g a r e s e t p u ls e
VA
C O M 0 ,C O M 1 ,C O M 2
VB
VSS
VA
A ll L C D d r iv e r o u tp u ts
VB
VSS
N o r m a l o p e r a tio n m o d e
*
*
*
VA
COM 0
VB
VSS
VA
COM 1
VB
VSS
VA
C O M 2*
VB
VSS
VA
L C D s e g m e n ts O N
VB
C O M 0 ,1 ,2 s id e s a r e u n lig h te d
VSS
O n ly L C D s e g m e n ts O N
C O M 0 s id e a r e lig h te d
VA
VB
VSS
O n ly L C D s e g m e n ts O N
C O M 1 s id e a r e lig h te d
VA
VB
VSS
O n ly L C D s e g m e n ts O N
VA
C O M 2 s id e a r e lig h te d
VB
VSS
L C D s e g m e n ts O N
C O M 0 ,1 s id e s a r e lig h te d
VA
VB
VSS
L C D s e g m e n ts O N
C O M 0 ,2 s id e s a r e lig h te d
VA
VB
VSS
L C D s e g m e n ts O N
C O M 1 ,2 s id e s a r e lig h te d
VA
VB
VSS
L C D s e g m e n ts O N
VA
C O M 0 ,1 ,2 s id e s a r e lig h te d
VB
VSS
H A LT M ode
VA
C O M 0 ,C O M 1 ,C O M 2 *
VB
VSS
VA
A ll L C D d r iv e r o u tp u ts
VB
VSS
N o te : " * " O m it th e C O M 2 s ig n a l, if th e 1 /2 d u ty L C D is u s e d .
V A = V L C D , V B = 1 /2 V L C D fo r H T 4 9 R 5 0 A -1 /H T 4 9 C 5 0 -1
V A = 2 V 2 , V B = V 2 , C ty p e fo r H T 4 9 C 5 0 L
LCD Driver Output (1/3 Duty, 1/2 Bias, R/C Type)
21
November 29, 2005