MAX6909 MAXIM [Maxim Integrated Products], MAX6909 Datasheet
MAX6909
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MAX6909 Summary of contents
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... PZT, is register selectable for one of four frequencies, can be turned on and off through a register bit, or selected when the ALM, alarm output, goes active. The MAX6909/MAX6910 are available in a 20-pin QSOP package and operate over the -40°C to +85°C temper- ature range. Point-of-Sale Equipment ...
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I C-Compatible Real-Time Clocks with µP Supervisor and NV RAM Controller ABSOLUTE MAXIMUM RATINGS All Voltages (with respect to GND) BATT or V ..........................................................-0.3V to +6.0V CC OUT, ALM, SCL, SDA, CX FAIL, PFO, RESET.......................................................-0.3V to +6.0V All Other ...
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I C-Compatible Real-Time Clocks with µP Supervisor and NV RAM Controller ELECTRICAL CHARACTERISTICS (continued -40°C to +85°C, unless otherwise noted. Typical values are CC(MIN) CC(MAX) A PARAMETER SYMBOL ...
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I C-Compatible Real-Time Clocks with µP Supervisor and NV RAM Controller ELECTRICAL CHARACTERISTICS (continued -40°C to +85°C, unless otherwise noted. Typical values are CC(MIN) CC(MAX) A PARAMETER SYMBOL ...
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I C-Compatible Real-Time Clocks with µP Supervisor and NV RAM Controller ELECTRICAL CHARACTERISTICS (continued -40°C to +85°C, unless otherwise noted. Typical values are CC(MIN) CC(MAX) A PARAMETER SYMBOL ...
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I C-Compatible Real-Time Clocks with µP Supervisor and NV RAM Controller AC ELECTRICAL CHARACTERISTICS (V < V < -40°C to +85°C, unless otherwise noted.) (Note 2) CC(MIN) CC CC(MAX) A PARAMETER SYMBOL 2-WIRE BUS TIMING ...
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I C-Compatible Real-Time Clocks with µP Supervisor and NV RAM Controller (V = 3.3V 3V +25°C, unless otherwise noted.) CC BATT OUT VOLTAGE CC vs. TEMPERATURE 100 ...
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I C-Compatible Real-Time Clocks with µP Supervisor and NV RAM Controller (V = 3.3V 3V +25°C, unless otherwise noted.) CC BATT A PFI-TO-PFO DELAY vs. TEMPERATURE 13.0 PFI FALLING AT 10V/ms 12.5 12.0 11.5 11.0 ...
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... Supply Output for CMOS RAM or Other ICs Requiring Use of Backup Battery Power. Bypass to GND with 2 OUT at least a 0.1µF capacitor. BATT ON Logic Output Open Drain. BATT ON is low when the MAX6909/MAX6910 are powered from BATT Chip-Enable Input. Input to the chip-enable switch used for external RAM. Connect to V ...
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... CRYSTAL- CX_FAIL FAIL DETECT WDI MR PFI CE_IN BATT OUT POWER V CC CONTROL GND BATT_ON SCL INPUT SHIFT REGISTERS SDA ALM Figure 1. MAX6909/MAX6910 Block Diagram 10 ______________________________________________________________________________________ FREQUENCY DIVIDERS SELECT SOURCE SELECT WATCHDOG TIMER DEBOUNCE CIRCUIT 1.2V 1Hz CONTROL LOGIC ADDRESS REGISTER RAM ...
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... This plane should be isolated from the regular PC board ground plane, should be no larger than the perimeter of the guard ring, and con- nected to the GND pin of the MAX6909/MAX6910. Ensure that this ground plane does not contribute to sig- nificant capacitance between signal line and ground on the connections that run from X1 and X2 to the crystal ...
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... ECS INC International ECS-.327-6.0-17 Fox Electronics FSM327 M-tron SX2010/ SX2020 Raltron RSE-32.768-6-C-T Timekeeping accuracy of the MAX6909/MAX6910 is dependent on the frequency stability of the external crystal. To determine frequency stability, use the para- bolic curve of Figure 3 and the following equations: ∆ ✕ k ✕ ...
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I C-Compatible Real-Time Clocks with µP Supervisor and NV RAM Controller Table 2. Acceptable Quartz Crystal Parameters PARAMETER Frequency Equivalent series resistance (ESR) Parallel load capacitance Q factor After 1 month that translates to: hr min ...
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I C-Compatible Real-Time Clocks with µP Supervisor and NV RAM Controller REGISTER ADDRESS FUNCTION SEC MIN DATE MONTH ...
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I C-Compatible Real-Time Clocks with µP Supervisor and NV RAM Controller REGISTER ADDRESS FUNCTION STATUS CONFIG ALARM THRESHOLDS: SEC MIN ...
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I C-Compatible Real-Time Clocks with µP Supervisor and NV RAM Controller Table 3. Hex Register Address/Description WRITE (HEX) READ (HEX Seconds 82 83 Minutes 84 85 Hours 86 87 Date 88 89 Month 8A 8B Day 8C ...
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... To minimize power consumption when operating from BATT, ≈ some functions are disabled; see Table 5. MAX6909/ MAX6910 functional blocks remain active when powered from battery can be connected prior to application of V with no current being drawn from the battery and the MAX6909/MAX6910 remaining inactive ...
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... The MAX6909/MAX6910 contain an integral POR circuit that ensures all registers are reset to a known state on power-up. On initial power-up, once V 0.75V (typ), the POR circuit releases the registers for normal operation. Should V (typ), the contents of the MAX6909/MAX6910 registers can no longer be guaranteed. ACTION R1 1.7kΩ ...
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I C-Compatible Real-Time Clocks with µP Supervisor and NV RAM Controller Table 5. MAX6910 I/O and IC Sections Powered from V DESCRIPTION Crystal Oscillator I/O Crystal Oscillator I/O Backup Power-Supply Input OUT (> BATT if V ...
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... Manual Reset Input Many microprocessor-based products require manual- reset capability, allowing the operator, a test techni- cian, or external logic circuitry to initiate a reset. With the MAX6909/MAX6910, a logic low on MR asserts reset. Reset remains asserted while MR is low, and for (Figure 7) after it returns high. MR has an internal t RP pullup resistor of typically 50kΩ ...
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... Figure 8. Interfacing to Microprocessors with Bidirectional Reset I/O ______________________________________________________________________________________ Transients CC The battery-on output, BATT ON open-drain out- put indicator of when the MAX6909/MAX6910 are pow- ered from the backup battery input, BATT. When V experi- falls below the reset threshold OUT switches from V asserted. When V threshold deasserted ...
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... CMOS RAM. The short CE propagation delay from OUT enables the MAX6909/MAX6910 to be used with most microproces- sors low when reset asserts, CE OUT remains low for typically t ...
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... RCE RESET CE IN Figure 13. Chip-Enable Timing Including MR Power-Fail Comparator The MAX6909/MAX6910 PFI is compared to an internal reference. If the PFI voltage is less than the power-fail ), PFO goes low. The power-fail com- threshold (V PFT parator is intended for use as an undervoltage detector to signal a failing power supply and can monitor either positive or negative supplies using a voltage-divider to PFI (Figure 26) ...
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... Figure 16. Piezo Transducer Functional Diagram CONDITION and GND through allow flex- OUT_PZT is designed low as OUT_PZT / ( calculated from where PZT OUT MAX6909/ MAX6910 R Rs OUT_PZT PZT PIEZO BUZZER V PZT PZT Low Selected frequency Selected frequency Low ...
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... RESET SERIAL INTERFACE input, which releases the SDA line from being held low BUS TIMEOUT This is necessary when the MAX6909/MAX6910 are transmitting data and become stuck at logic low. If the SDA line is stuck low, any other device on the bus is not able to communicate. The logic above, shown in Figure 18, is intended to illustrate the timeout feature ...
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I C-Compatible Real-Time Clocks with µP Supervisor and NV RAM Controller 1Hz_CLK TIME_OUT_CLR VALID START CONDITION SDA SCL TIME_OUT Figure 19. Normal 2-Wire Bus Operation 1Hz_CLK TIME_OUT_CLR VALID START CONDITION SDA SCL TIME_OUT t1 Figure 20. Timeout 2-Wire Bus ...
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... Figure 24. Address/Command Byte ______________________________________________________________________________________ The command byte is shown in Figure 24. The MSB (bit 7) must be a logic zero, writes to the MAX6909/ MAX6910 are disabled. Bit 6 specifies clock/calendar data if logic 0 or RAM data if logic 1. Bits 1 through 5 specify the designated registers to be input or output, and ...
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... A : ACKNOWLEDGE FROM MASTER NOT ACKNOWLEDGE FROM MASTER M Figure 25. MAX6909/MAX6910 Data Transfer 28 ______________________________________________________________________________________ If single write operations are to be used to write to each of the timekeeping registers, then error checking is needed. If the seconds register updated, update it first and then read it back and store its value as the initial seconds ...
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... PFO and PFI (Figure 27(a)). Select the ratio of R1 and R2 such that PFI sees V trip point (V should typically be more than 10 times the value R2. The hysteresis window extends both above (V and below ( PFI MAX6909/ MAX6910 V IN PFO MR GND ...
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... V CC PFI C1 R3 MAX6909/ MAX6910 PFO GND TO µ TRIP ...
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... No No TRANSISTOR COUNT: 35,267 Yes PROCESS: BiCMOS Yes Pin Configuration TOP VIEW BATT OUT 2 19 RESET BATT RESET OUT MAX6909/ PFI 5 16 PFO MAX6910 PZT WDI 7 14 ALM GND 8 13 SCL SDA FAIL ...
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... RPU RPU = BUS µCONTROLLER CE INTO RESET NMI 3.3V 3.3V MULTIFUNCTION ASIC PFO CX FAIL RST 32 ______________________________________________________________________________________ 12V 6.98kΩ PFI WDI MAX6909/ 3.0V 3.3V MAX6910 MR 0.1µF BATT RPU V BATT SCL SDA OUT 1µF* CMOS RAM CE OUT CE 47kΩ Typical Operating Circuit V BATT BATTERY-ON INDICATOR PFO 150kΩ ...
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I C-Compatible Real-Time Clocks with µP Supervisor and NV RAM Controller (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) Maxim cannot assume responsibility for ...