R-22AT

R-24AT

TOUCH CONTROL PANEL ASSEMBLY

OUTLINE OF TOUCH CONTROL PANEL

The touch control section consists of the following units as shown in the touch control panel circuit.

(1)Control Unit

(2)Key Unit

The principal functions of these units and the signals communicated among them are explained below.

2. Key Unit

The key unit is composed of a matrix circuit in which when a key it touched, one of signals P33 - P34 generated by the LSI, is passed through the key and returned to the LSI as one of signals P24 - P27. This model has 20 Memory pads. When the oven is shipped, Memory pad 1 to 10 are set as follows: fig.1.

1.Control Unit

Signal of key touch and oven function control are all processed by one microcomputer.

1)Power Supply Circuit

This circuit changes output voltage at the secondary side of the touch control transformer to voltages re- quired at each part by full wave rectifying circuit, constant voltage circuit, etc..

2)Reset Circuit

This is an Auto-clear Circuit, i.e., a reset circuit, which enables IC1 to be activated from initial state.

3)Power Synchronizing Signal Generating Circuit This is a circuit for generating power synchronizing signal by virtue of the secondary side output of touch control transformer.

This signal is used for a basic frequency to time processing and so on.

4)Clock Circuit

This is a circuit for controlling clock frequency required for operating I-1.

5)I-1 (Main Processor)

This is a one-chip microcomputer, responsible for controlling the entire control unit.

6)I-2 (Memory Processor)

This is a memory IC, responsible for memory function.

7)Display Circuit

This is a circuit for driving display tubes by I-1 output.

8)Key Input Circuit

This is a circuit for transmitting key input information to I-1.

9)Sound-body Driving Circuit

This is a circuit for driving sound body by I-1 output.

10)Relay Driving Circuit

This is a circuit for driving output relay by I-1 output.

11)Stop Switch Circuit

This is a circuit for driving I-1 to detect door opening/ closing.

12)Exhaust Air Temperature Detecting Circuit

This is a circuit for transmitting output change of thermistor (Exhaust thermistor) to I-1.

13)Magnetron Temperature Circuit. (Detect Noload or Fan Lock)

This is a circuit for transmitting output change of thermistor (Magnetron thermistor) to I-1.

Memory No.

Cook Time

Output Power

1

5 sec.

100%

2

10 sec.

100%

3

20 sec.

100%

4

30 sec.

100%

5

40 sec.

100%

6

50 sec.

100%

7

1 min.

100%

8

1 min. 15 sec.

100%

9

1 min.30 sec.

100%

0

2 mins.

100%

 

 

 

(fig. 1)

This model has a double quantity pad. When the oven is shipped, Magnification "1.8" is preset in the double quantity pad. This model has an defrost pad. When the oven is shipped, defrost is set as follows: fig.2.

 

1STAGE

2STAGE

3STAGE

POWER

40%

30%

20%

DEFROSTING TIME

0.2T+20sec

0.13T+30sec.

0.67T-50sec.

(fig. 2)

NOTE :

"CHECK" indicator will flash at half of defrosting time.

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Sharp R-24AT, R-22AT service manual Touch Control Panel Assembly

R-22AT, R-24AT specifications

The Sharp R-24AT and R-22AT microwave ovens are advanced kitchen appliances designed to enhance cooking convenience, efficiency, and versatility. Both models incorporate innovative technologies and features that cater to modern cooking needs.

The Sharp R-24AT boasts a robust 900 watts of cooking power, enabling users to prepare a wide variety of meals quickly and effectively. Its spacious 24-liter capacity is suitable for families and those who enjoy entertaining. One of the standout features of the R-24AT is its intelligent sensor technology, which automatically detects humidity levels in the cooking food. This innovative feature ensures optimal cooking times and temperatures, resulting in perfectly cooked dishes without the guesswork.

Another key technology in the R-24AT is the inverter cooking system. This system provides a seamless flow of power throughout the cooking process, allowing for more precise temperature control. Unlike traditional microwaves that operate in full power or off, inverter technology ensures consistent heat, which is particularly beneficial for tasks such as defrosting, reheating, and simmering.

The Sharp R-22AT, while slightly more compact with a 22-liter capacity, also delivers impressive performance with 800 watts of power. It features a similar inverter cooking system that guarantees even cooking results. Both models come with multiple auto-cook presets, providing users with a selection of quick options for common dishes such as popcorn, pizza, and oatmeal. This feature streamlines meal preparation and reduces the time spent on planning meals.

In addition, the user-friendly control panel on both models includes a combination of push-button and rotary dial controls for easy navigation. The inclusion of a bright LED display further enhances usability, allowing cooks to monitor cooking times and settings easily.

Safety is another critical aspect of the Sharp R-24AT and R-22AT. Both models come equipped with a child lock feature, ensuring peace of mind in homes with young children. The stainless steel interiors of these microwaves facilitate easy cleaning, while their sleek design adds a modern touch to any kitchen.

In summary, the Sharp R-24AT and R-22AT microwave ovens stand out for their advanced cooking technologies, user-friendly features, and thoughtful design. They empower home cooks to prepare meals with precision and ease, making them a valuable addition to any kitchen.