LCD segment driver series | New product new technology

Overview

ROHM LCD segment drivers feature internal RAM that lightens microcontroller load while simplifying wiring layout. In addition, the low power consumption design makes continuous LCD viewing possible in portable devices.
A wide lineup is offered, including models with built-in GPO that takes care of microcontroller port shortage, units with integrated LED driver, and ICs equipped with a PWM generator for LED dimming capability. ROHM segment drivers reduce microcontroller load, eliminating the number of external parts required while contributing to greater energy savings.

Features (BU9798GUW)

LCD drive output: Common 4-line output, 49-line segment output
Built-in data RAM (DDRAM capacity: 196bits) lightens CPU load
3-line serial interface (SD, SCL, CSB)
1/3 Bias-1/3 or 1/4 Duty, 1/1 Bias-1/1 Duty (Static Driving)
Integrated buffer amp
Built-in regulator for LCD drive (3.2, 3.3, 3.4, 4.4, 4.5, 4.6, 5.0V)
Independent power supply design for LCD drive
Switching possible between the segment output port and general purpose output port
Integrated LED drive circuit
Port switching function between segment output and LED drive
PWM generator - Internal switching possible
(8bit/12bit selectable resolution)
Low power consumption design
Equipped with standby mode
Built-in Power ON Reset function
Integrated blink function
Individual blink ON/OFF operation possible for each segment
Adjustable blink frequency (1.6/2.0/2.6/4.0Hz)

Feature 1: Low current consumption (<10µA) ideal for portable devices

Low power amp and oscillator technologies are utilized for significantly lower power consumption. In addition, a buffer amp is built in, and large voltage dividing resistors can be used, making it possible to reduce current consumption.

Feature 2: ROHM offers drivers to meet virtually any need, from a few to many dots

The broad lineup is available in a variety of duty cycle, bias input, and display size specifications.

Feature 3: LED driver/PWM generator and GPO built in, eliminating microcontroller port shortage problems

ROHM offers LCD segment drivers with a built-in LED driver that provides the necessary current to drive status displays. In addition, the LED driver is capable of ON/OFF control from an integrated PWM generator, resulting in LED dimming capability.
The BU9798KV features 49 output ports, 31 of which can be used for GPO, making it compatible with LCDs of various sizes.

●BU9798KV : 49-segment output ports
[31-port (max.) GPO capability]
●BU97930MUV : 27-segment output ports
[4-port (max.) GPO capability]
●BU97931FV : 28-segment output ports
[5-port (max.) GPO capability]

Adjust the number of ports for segment/GPO use

Lineup

Part No.	Display	Outputs		Operating Voltage		Duty	Bias	Interface	RAM	EVR	LDO	GPO	LED Dr	PWM Gen.	Package
Part No.	Display	SEG	COM	I/F Power Supply (VDD)	LCD Power Supply (VLCD)	Duty	Bias	Interface	RAM	EVR	LDO	GPO	LED Dr	PWM Gen.	Package
BU9796FS	80 dots	20	4	2.5V to 5.5V		1/4, 1/3	1/2, 1/3	2 line serial	○	-	-	-	-	-	SSOPA-32
NEW BU97930MUV	108 dots	27	4	1.8V to 3.6V	2.7V to 5.5V	1/4, 1/3, Static	1/3, Static	3 line serial	○	-	-	○ 4 port	○ 1 port	○ 1 ch	VQFN40V6060
NEW BU97931FV	112 dots	28	4	1.8V to 3.6V	2.7V to 5.5V	1/4, 1/3, Static	1/3, Static	3 line serial	○	-	-	○ 5 port	○ 1 port	○ 1 ch	SSOP-B40
BU9795AKV	140 dots	35	4	2.5V to 5.5V		1/4, 1/3	1/2, 1/3	3 line serial	○	-	-	-	-	-	VQFP48C
BU9795FV	108 dots	27	4	2.5V to 5.5V		1/4, 1/3	1/2, 1/3	3 line serial	○	-	-	-	-	-	SSOP-B40
BU9795GUW	124 dots	31	4	2.5V to 5.5V		1/4, 1/3	1/2, 1/3	3 line serial	○	-	-	-	-	-	VBGA048W040
NEW BU9798KV /GUW	196 dots	49	4	1.8V to 3.6V	3.3V to 5.5V	1/4, 1/3, Static	1/3, Static	3 line serial	○	-	○	○ 31 port	○ 3 port	○ 2 ch	VQFP64/ VBGA063W050
BU9794KV	200 dots	50	4	2.5V to 5.5V	2.5V to 5.5V	1/4, 1/3	1/2, 1/3	3 line serial	○	-	-	-	-	-	VQFP64
NEW BU9799KV	200 dots	50	4	2.5V to 5.5V	2.5V to 5.5V	1/4, 1/3	1/2, 1/3	2 line serial	○	○					VQFP64