HA1848P HITACHI, HA1848P Datasheet

no-image

HA1848P

Manufacturer Part Number
HA1848P
Description
Watchdog Timer
Manufacturer
HITACHI
Datasheet

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Part Number:
HA1848P
Manufacturer:
HITACHI/日立
Quantity:
20 000
Description
The HA1835P and HA1848P is a monolithic voltage regulator control designed for microcomputer
systems. In addition to the voltage regulator, it include watchdog timer function and power-on reset
function.
These ICs can perform many function in various microcomputer systems with few external parts.
Features
Regulated power supply control function
Watchdog timer
Automatic reset
Built-in overcurrent limiter for external PNP-type transistor
Internal bandpass filter control circuit (pulse width detect type) and reset signal oscillator
Automatic power-on reset
Pulse generator characteristics can be set by external resistor (R
Alternative between RES and RES output
Wide area of operational voltage; V
Available external PNP-type transistor, suited to any system power supply
Output voltage can be adjusted exactry in the range from 4 V to 6 V
Fail-safe utility
Bandpass filter characteristics can be set by external resister (Rf) and capacitance (Cf)
HA1835P/HA1848P
Watchdog Timer
CC
= 6 V to 30 V
R
) and capacitance (C
R
)

Related parts for HA1848P

HA1848P Summary of contents

Page 1

... HA1835P/HA1848P Description The HA1835P and HA1848P is a monolithic voltage regulator control designed for microcomputer systems. In addition to the voltage regulator, it include watchdog timer function and power-on reset function. These ICs can perform many function in various microcomputer systems with few external parts. Features Regulated power supply control function Wide area of operational voltage ...

Page 2

... Reset pulse output terminal for high level reset type microcomputer Note: RES and RES are open-collector output terminals, so connect a pull-up resistor of about P-RUN Vout 6 9 GND 7 8 (Top View) Note: HA1848P: 9 pin is non connection 500 k and CS CC RES RES CONT Comp * Vadj ...

Page 3

... Block Diagram Reference Voltage Fail Detector P-RUN 3 (Band Pass Filter) 7 GND Note: HA1848P: 9 pin is non connection Current Limiter Error Amp Power on Reset Detector Reset Signal Oscillator 300 k 0.01 F 560 k HA1835P/HA1848P Vout Vout HA1835P CONT Comp * 8 Vadj RES 13 RES 0 ...

Page 4

... HA1835P/HA1848P Absolute Maximum Ratings (Ta = 25°C) Item Supply voltage P-RUN input voltage Output voltage Output current Control terminal voltage Control terminal current Power dissipation (Note) Operating temperature range Storage temperature range Soldering temperature Note > derate by 8.3 mW Symbol Rating –0.3 to Vout P-RUN V 17 ...

Page 5

... OL1 I — — 5.0 OH1 I — — 30 OH3 t 80 130 200 130 220 off 160 100 200 RH HA1835P/HA1848P Unit Test Conditions 17.5 V (No load), CC with PNP transistor 17.5 V, Iout = 0 17.5 V, Iout = 17.5 V, Iout = Iout = 0 0.5 Vrms kHz 0.2 SC mV/ C ...

Page 6

... HA1835P/HA1848P Test Circuit 0 Batt 2SB857D 3 10 P-RUN V CONT HA1835P Cf GND 300 k 0.01 F Vout RES 14 RES 13 Vadj 8 Counter 560 k 0 100 F ...

Page 7

... CC 0 Iout (Limit) Power-On Reset The HA1835P, and HA1848P can output a reset pulse to start the microcomputer at power on (figure 6). The external resistor R and capacitor C R Note that RES and RES are open-collector terminals. They should therefore be connected to a pull-up resistor of about Watchdog Timer The watchdog timer is a fail-safe function ...

Page 8

... HA1835P/HA1848P Application Circuit Example V Batt 300 P-RUN RES 2SB857D 0 Vout CC CONT Cf GND 0.01 F System burst t Reset output signal Power-on reset signal + RES RES 13 Microcomputer system P-RUN 3 I/O port 560 k 0 off Reg C 2 100 F ...

Page 9

... Characteristic Curves 5.1 5.0 4 0.1 A OUT 0 Input voltage Figure 1 Output Voltage vs. Input Voltage 0 Output current Figure 2 Output Voltage vs. Output Current 50 0 Ambient temperature Figure 3 Output Voltage vs. Ambient Temperature HA1835P/HA1848P ( 0 (A) OUT OUT 50 100 ...

Page 10

... HA1835P/HA1848P 200 100 200 100 100 100 k 200 k Resistor R Figure 4 Automatic Reset Pulse High Time vs. Resistor = 100 k 200 k Resistor R Figure 5 Automatic Reset Pulse Low Time vs. Resistor = 100 k 200 k Resistor R Figure 6 Power-on Reset Time vs. Resistor 500 500 500 ...

Page 11

... Duty = Clock pulse duty cycle (%) Figure 7 Clock Pulse Frequency vs. Clock Pulse Duty Cycle Duty = 50 System run-away sense region 500 Normal operation region 200 100 50 System run-away sense region 20 100 k 200 k Resistor Figure 8 Clock Pulse Frequency vs. Resistor HA1835P/HA1848P 100 500 k 11 ...

Page 12

... HA1835P/HA1848P Package Dimensions 14 1 2.39 Max 2.54 0.25 12 19.20 20.32 Max 8 7 1.30 0.48 0.10 7.62 + 0.10 0.25 – 0.05 0 – 15 Hitachi Code DP-14 JEDEC Conforms EIAJ Conforms Mass (reference value) 0.97 g Unit: mm ...

Page 13

... Whitebrook Park Lower Cookham Road Maidenhead Berkshire SL6 8YA, United Kingdom Tel: <44> (1628) 585000 Fax: <44> (1628) 778322 HA1835P/HA1848P Hitachi Asia (Hong Kong) Ltd. Hitachi Asia Pte. Ltd. Group III (Electronic Components) 16 Collyer Quay #20-00 7/F., North Tower, World Finance Centre, ...

Related keywords