HT49C50L datasheet(21/45 Pages) HOLTEK

21 / 45 page

HT49R50A-1/HT49C50-1/HT49C50L

Rev. 2.00

November 29, 2005

N o r m a l o p e r a t i o n m o d e

D u r i n g a r e s e t p u l s e

C O M 0 , C O M 1 , C O M 2

V A

V B

V S S

A l l L C D d r i v e r o u t p u t s

C O M 0

C O M 1

C O M 2 *

H A L T M o d e

C O M 0 , C O M 1 , C O M 2 *

A l l L C D d r i v e r o u t p u t s

V A

V B

V A

V B

V S S

V A

V B

V A

V B

V S S

V A

V B

V A

V B

V S S

V A

V B

V A

V B

V S S

V A

V B

V S S

V A

V B

V S S

V A

V B

V S S

V A

V B

V S S

V A

V B

V S S

V A

V B

L C D s e g m e n t s O N

C O M 0 , 1 , 2 s i d e s a r e u n l i g h t e d

O n l y L C D s e g m e n t s O N

C O M 0 s i d e a r e l i g h t e d

O n l y L C D s e g m e n t s O N

C O M 1 s i d e a r e l i g h t e d

O n l y L C D s e g m e n t s O N

C O M 2 s i d e a r e l i g h t e d

L C D s e g m e n t s O N

C O M 0 , 1 s i d e s a r e l i g h t e d

L C D s e g m e n t s O N

C O M 0 , 2 s i d e s a r e l i g h t e d

L C D s e g m e n t s O N

C O M 1 , 2 s i d e s a r e l i g h t e d

L C D s e g m e n t s O N

C O M 0 , 1 , 2 s i d e s a r e l i g h t e d

N o t e : " * " O m i t t h e C O M 2 s i g n a l , i f t h e 1 / 2 d u t y L C D i s u s e d .

V A = V L C D , V B = 1 / 2 V L C D f o 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 t y p e f o r H T 4 9 C 5 0 L

LCD Driver Output (1/3 Duty, 1/2 Bias, R/C Type)

LCD Driver Output

The output number of the LCD driver device can be

´2, 33´3or32´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.

HT49C50L Datasheet(PDF) 21 Page - Holtek Semiconductor Inc

HT49C50L Datasheet(HTML) 21 Page - Holtek Semiconductor Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45

Datasheet Download

Link URL